Update frontend

Implement inotify based pipe connector

.drone.yml

@@ -1,13 +0,0 @@
-pipeline:
-  build:
-    image: eu.gcr.io/avatao-public/docker:el7
-    volumes:
-      - /etc/docker:/etc/docker:ro
-      - /root/.docker:/root/.docker:ro
-      - /var/run/docker.sock:/var/run/docker.sock:ro
-    commands:
-      - docker build --pull -t eu.gcr.io/avatao-challengestore/tutorial-framework:${DRONE_TAG} .
-      - docker push eu.gcr.io/avatao-challengestore/tutorial-framework:${DRONE_TAG}
-    when:
-      event: 'tag'
-      branch: refs/tags/mainecoon-20*

.pylintrc

@@ -3,3 +3,10 @@
 ignored-modules = zmq
 max-line-length = 120
 disable = missing-docstring, too-few-public-methods, invalid-name
+
+[SIMILARITIES]
+
+min-similarity-lines=8
+ignore-comments=yes
+ignore-docstrings=yes
+ignore-imports=yes

COPYING

@@ -0,0 +1,674 @@
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+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

COPYING.LESSER

@@ -0,0 +1,165 @@
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
+   this License applicable to that copy.
+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
+a header file that is part of the Library.  You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
+       License, and the Corresponding Application Code in a form
+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
+       Library.  A suitable mechanism is one that (a) uses at run time
+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.

Dockerfile

@@ -1,29 +1,33 @@
+FROM avatao/frontend-tutorial-framework:chausie-20191021 as frontend
 FROM avatao/debian:buster
 
-RUN curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -                                     &&\
-    curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -                             &&\
-    echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list &&\
-    apt-get update                                                                                     &&\
+RUN apt-get update                           &&\
     apt-get install -y --no-install-recommends \
-        nodejs                                 \
-        yarn                                   \
         supervisor                             \
+        ncat                                   \
         libzmq5                                \
         nginx                                  \
-        gettext-base                                                                                   &&\
-    rm -rf /var/lib/apt/lists/*                                                                        &&\
+        jq                                     \
+        gettext-base                         &&\
+    rm -rf /var/lib/apt/lists/*              &&\
     ln -sf /bin/bash /bin/sh
 
 COPY requirements.txt /tmp
 RUN pip3 install -r /tmp/requirements.txt
 
-ENV TFW_PUBLIC_PORT=8888          \
-    TFW_WEB_PORT=4242             \
-    TFW_LOGIN_APP_PORT=6666       \
-    TFW_TERMINADO_PORT=7878       \
-    TFW_SUPERVISOR_HTTP_PORT=9001 \
-    TFW_PUBLISHER_PORT=7654       \
-    TFW_RECEIVER_PORT=8765
+RUN curl -Ls https://github.com/krallin/tini/releases/download/v0.18.0/tini-amd64 --output /bin/init &&\
+    echo "12d20136605531b09a2c2dac02ccee85e1b874eb322ef6baf7561cd93f93c855 /bin/init"                 |\
+    sha256sum --check --status                                                                       &&\
+    chmod 755 /bin/init
+
+ENV TFW_PUBLIC_PORT=8888            \
+    TFW_WEB_PORT=4242               \
+    TFW_LOGIN_APP_PORT=6666         \
+    TFW_TERMINAL_PORT=7878          \
+    TFW_TERMINAL_FALLBACK_PORT=7879 \
+    TFW_SUPERVISOR_HTTP_PORT=9001   \
+    TFW_PUB_PORT=7654               \
+    TFW_PULL_PORT=8765
 
 EXPOSE ${TFW_PUBLIC_PORT}
 
@@ -34,31 +38,30 @@ ENV PYTHONPATH="/usr/local/lib"                                            \
     TFW_NGINX_CONF="/etc/nginx/nginx.conf"                                 \
     TFW_NGINX_DEFAULT="/etc/nginx/sites-enabled/default"                   \
     TFW_NGINX_COMPONENTS="/etc/nginx/components"                           \
-    TFW_LIB_DIR="/usr/local/lib/"                                          \
-    TFW_TERMINADO_DIR="/tmp/terminado_server"                              \
+    TFW_LIB_DIR="/usr/local/lib"                                           \
     TFW_FRONTEND_DIR="/srv/frontend"                                       \
-    TFW_SERVER_DIR="/srv/.tfw"                                             \
+    TFW_DIR="/.tfw"                                                        \
+    TFW_SERVER_DIR="/.tfw/tfw_server"                                      \
+    TFW_AUTH_KEY="/tmp/tfw-auth.key"                                       \
+    TFW_LOGS_DIR="/var/log/tfw"                                            \
+    TFW_PIPES_DIR="/run/tfw"                                               \
+    TFW_SNAPSHOTS_DIR="/tmp/tfw-snapshots"                                 \
     TFW_HISTFILE="/home/${AVATAO_USER}/.bash_history"                      \
     PROMPT_COMMAND="history -a"
 
-COPY bashrc /tmp
-RUN echo "export HISTFILE=${TFW_HISTFILE}" >> /tmp/bashrc &&\
-    cat /tmp/bashrc >> /home/${AVATAO_USER}/.bashrc
-
+COPY bashrc supervisor/tfw_init.sh /tmp/
 COPY supervisor/supervisord.conf ${TFW_SUPERVISORD_CONF}
 COPY supervisor/components/ ${TFW_SUPERVISORD_COMPONENTS}
 COPY nginx/nginx.conf ${TFW_NGINX_CONF}
 COPY nginx/default.conf ${TFW_NGINX_DEFAULT}
 COPY nginx/components/ ${TFW_NGINX_COMPONENTS}
-COPY lib LICENSE ${TFW_LIB_DIR}
+COPY tfw ${TFW_LIB_DIR}/tfw
 COPY supervisor/tfw_server.py ${TFW_SERVER_DIR}/
+COPY --from=frontend /srv/dist ${TFW_FRONTEND_DIR}
 
-RUN for dir in "${TFW_LIB_DIR}"/{tfw,tao,envvars} "/etc/nginx" "/etc/supervisor"; do \
-        chown -R root:root "$dir" && chmod -R 700 "$dir";                            \
-    done
+VOLUME ["${TFW_LOGS_DIR}", "${TFW_PIPES_DIR}"]
 
 ONBUILD ARG BUILD_CONTEXT="solvable"
-ONBUILD ARG NOFRONTEND=""
 
 ONBUILD COPY ${BUILD_CONTEXT}/nginx/ ${TFW_NGINX_COMPONENTS}
 ONBUILD COPY ${BUILD_CONTEXT}/supervisor/ ${TFW_SUPERVISORD_COMPONENTS}
@@ -66,11 +69,7 @@ ONBUILD COPY ${BUILD_CONTEXT}/supervisor/ ${TFW_SUPERVISORD_COMPONENTS}
 ONBUILD RUN for f in "${TFW_NGINX_DEFAULT}" ${TFW_NGINX_COMPONENTS}/*.conf; do                               \
                 envsubst "$(printenv | cut -d= -f1 | grep TFW_ | sed -e 's/^/$/g')" < $f > $f~ && mv $f~ $f ;\
             done
-ONBUILD VOLUME ["/etc/nginx", "/var/lib/nginx", "/var/log/nginx"]
+ONBUILD VOLUME ["/etc/nginx", "/var/lib/nginx", "/var/log/nginx", "${TFW_LIB_DIR}/tfw"]
 
-ONBUILD COPY ${BUILD_CONTEXT}/frontend /data/
-ONBUILD RUN test -z "${NOFRONTEND}" && cd /data && yarn install --frozen-lockfile || :
-ONBUILD RUN test -z "${NOFRONTEND}" && cd /data && yarn build --no-progress || :
-ONBUILD RUN test -z "${NOFRONTEND}" && mv /data/dist ${TFW_FRONTEND_DIR} && rm -rf /data || :
-
-CMD exec supervisord --nodaemon
+ENTRYPOINT ["/bin/init", "--"]
+CMD exec supervisord --nodaemon --configuration ${TFW_SUPERVISORD_CONF}

LICENSE

@@ -1,12 +0,0 @@
-AVATAO CONFIDENTIAL
-
-Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-All Rights Reserved.
-
-All source code, configuration files and documentation contained herein
-is, and remains the exclusive property of Avatao.com Innovative Learning Kft.
-The intellectual and technical concepts contained herein are proprietary 
-to Avatao.com Innovative Learning Kft. and are protected by trade secret
-or copyright law. Dissemination of this information or reproduction of
-this material is strictly forbidden unless prior written permission is
-obtained from Avatao.com Innovative Learning Kft.

README.md

@@ -1,268 +1,5 @@
 # baseimage-tutorial-framework
 
-This is the beating heart of TFW – the Docker baseimage containing the internals of the framework.
+This is the beating heart of TFW – the Docker baseimage containing the internals of the framework. It's most important element is the robust messaging system that makes it straightforward to implement interactive exercises.
 
-Every tutorial-framework based challenge has a `solvable` Docker image based on this one: their `Dockerfile`s begin with `FROM eu.gcr.io/avatao-challengestore/tutorial-framework`.
-Note that TFW is not avaliable on Docker Hub due to legal reasons and is only accessible through local builds (don't worry, we've got you covered with build scripts in the [test-tutorial-framework](https://github.com/avatao-content/test-tutorial-framework) repo).
-
-This document explains the general concepts of TFW and should be the first thing you read before getting started with development.
-
-For more on building and running you should check the [test-tutorial-framework](https://github.com/avatao-content/test-tutorial-framework) repo.
-
-## The framework
-
-The goal of the tutorial-framework is to help content developers in creating interactive tutorials for the Avatao platform.
-
-To make this possible TFW implements a robust messaging system and provides several pre-written components built upon it, such as a file editor and a terminal (both running in your browser).
-
-The foundation of the whole framework is the messaging system connecting the frontend with the backend.
-Frontend components use websockets to connect to the TFW server, to which you can hook several *event handlers* defining how to handle specific messages.
-
-![TFW architecture](docs/tfw_architecture.png)
-
-### Networking details
-
-Event handlers connect to the TFW server using ZMQ.
-They receive messages on their `SUB`(scribe) sockets, which are connected to the `PUB`(lish) socket of the server.
-Event handlers reply on their `PUSH` socket, then their messages are received on the `PULL` socket of the server.
-
-The TFW server is basically just a fancy proxy.
-It's behaviour is quite simple: it proxies every message received from the fontend to the event handlers and vice versa.
-
-The server is also capable of "mirroring" messages back to their source.
-This is useful for communication between event handlers or frontend components (event handler to event handler or frontend component to frontend component communication).
-
-Components can also broadcast messages (broadcasted messages are received both by event handlers and the frontend as well).
-
-### Event handlers
-
-Imagine event handlers as callbacks that are invoked when TFW receives a specific type of message. For instance, you could send a message to the framework when the user does something of note.
-
-Event handler allow you to define actions triggered on the backend when the user presses a button on the frontend or moves the cursor to a specific area, etc.
-
-Event handlers use ZeroMQ to connect to the framework. Due to this they are as loosely-coupled as possible: usually they are running in separate processes and only communicate with TFW through ZMQ.
-
-Our pre-made event handlers are written in Python3, but you can write event handlers in any language that has ZeroMQ bindings (this means virtually any language).
-
-This makes the framework really flexible: you can demonstrate the concepts you want to in any language while using the same set of tools provided by TFW.
-Inside Avatao this means that any of the content teams can use the framework with ease.
-
-### FSM
-
-Another unique feature of the framework is the FSM – finite state machine – representing the state of your challenge.
-This allows you to track users progressing with the tasks you've defined for them to complete.
-
-For instance, you could represent whether the user managed to create a malicious user with a state called `user_registered` and subscribe callbacks to events regarding that state (like entering or leaving).
-
-You could create challenges that can be completed in several different ways: imagine a state called `challenge_complete`, which indicates if the challenge is completed. Several series of actions (triggers) could lead to this state.
-
-This enables you to guide your users through the experience you've envisioned with your tutorial.
-We can provide a whole new level of interactivity in our challenges because we know what the user is doing.
-This includes context-dependent hints and the automatic typing of commands to a terminal.
-
-### Frontend
-
-Note that our frontend implementation is written in Angular. It is maintained and documented in the [frontend-tutorial-framework](https://github.com/avatao-content/frontend-tutorial-framework) repository.
-
-### Messaging format
-
-The framework uses JSON messages internally and in exposed APIs as well.
-These messages must comply with some rules.
-Don't worry, we are not too fond of rules around these parts.
-
-The TFW message format:
-
-```text
-{
-    "key: "some identifier used for addressing",
-    "data":
-    {
-        ...
-        JSON object carrying anything, preferably cats
-        ...
-    },
-    "trigger": "FSM action"
-}
-```
-
-- The `key` field is used by TFW for addressing and every message must have one (it can be an empty string though)
-- The `data` object can contain anything you might want to send
-- The `trigger` key is an optional field that triggers an FSM action with that name from the current state (whatever that might be)
-
-To mirror messages back to their sources you can use a special messaging format, in which the message to be mirrored is enveloped inside the `data` field of the outer message:
-
-```text
-    "key": "mirror",
-    "data":
-    {
-        ...
-        The message you want to mirror (with it's own "key" and "data" fields)
-        ...
-    }
-```
-
-Broadcasting messages is possible in a similar manner by using `"key": "broadcast"` in the outer message.
-
-## Where to go next
-
-Most of the components you need have docstrings included (hang on tight, this is work in progress) – refer to them for usage info.
-
-In the `docs` folder you can find our Sphinx-based documentation, which you can build using the `hack/tfw.sh` script in the [test-tutorial-framework](https://github.com/avatao-content/test-tutorial-framework) repository.
-
-To get started you should take a look at [test-tutorial-framework](https://github.com/avatao-content/test-tutorial-framework), which serves as an example project as well.
-
-## API
-
-APIs exposed by our pre-witten event handlers are documented here.
-
-### IdeEventHandler
-
-You can read the content of the currently selected file like so:
-```
-{ 
-    "key": "ide",
-    "data":
-    {
-        "command": "read"
-    }
-}
-```
-
-Use the following message to overwrite the content of the currently selected file:
-```
-{ 
-    "key": "ide",
-    "data":
-    {
-        "command": "write",
-        "content": ...string...
-    }
-}
-```
-
-To select a file use the following message:
-```
-{ 
-    "key": "ide",
-    "data":
-    {
-        "command": "select",
-        "filename": ...string...
-    }
-}
-```
-
-You can switch to a new working directory using this message (note that the directory must be in `allowed_directories`):
-```
-{ 
-    "key": "ide",
-    "data":
-    {
-        "command": "selectdir",
-        "directory": ...string...
-    }
-}
-```
-
-Overwriting the current list of excluded file patterns is possible with this message:
-```
-{ 
-    "key": "ide",
-    "data":
-    {
-        "command": "exclude",
-        "exclude": ...array of strings...
-    }
-}
-```
-
-### TerminalEventHandler
-
-Writing to the terminal:
-```
-{ 
-    "key": "shell",
-    "data":
-    {
-        "command": "write",
-        "value": ...string...
-    }
-}
-```
-
-You can read terminal command history like so:
-```
-{ 
-    "key": "shell",
-    "data":
-    {
-        "command": "read",
-        "count": ...number...
-    }
-}
-```
-
-### ProcessManagingEventHandler
-
-Starting, stopping and restarting supervisor processes can be done using similar messages (where `command` is `start`, `stop` or `restart`):
-```
-{ 
-    "key": "processmanager",
-    "data":
-    {
-        "command": ...string...,
-        "process_name": ...string...
-    }
-}
-```
-
-### LogMonitoringEventHandler
-
-To change which supervisor process is monitored use this message:
-```
-{ 
-    "key": "logmonitor",
-    "data" :
-    {
-        "command": "process_name",
-        "value": ...string...
-    }
-}
-```
-
-To set the tail length of logs (the monitor will send back the last `value` characters of the log):
-```
-{ 
-    "key": "logmonitor",
-    "data" :
-    {
-        "command": "log_tail",
-        "value": ...number...
-    }
-}
-```
-
-### FSMManagingEventHandler
-
-To attempt executing a trigger on the FSM use:
-```
-{
-    "key": "fsm",
-    "data" :
-    {
-        "command": "trigger",
-        "value": ...string...
-    }
-}
-```
-
-To force the broadcasting of an FSM update you can use this message:
-```
-{
-    "key": "fsm",
-    "data" :
-    {
-        "command": "update"
-    }
-}
-```
+To learn more about the framework and get started, please consult our [wiki](https://github.com/avatao-content/baseimage-tutorial-framework/wiki).

VERSION

@@ -1 +1 @@
-mainecoon
+chausie

docs/source/components/components.rst

@@ -23,3 +23,10 @@ Components
 
 .. autoclass:: BashMonitor
     :members:
+
+.. autoclass:: FSMManagingEventHandler
+    :members:
+
+.. autoclass:: CommandsEqual
+    :members:
+

docs/source/foundations/eventhandlers.rst

@@ -3,10 +3,13 @@ Event handler base classes
 
 Subclass these to create your cusom event handlers.
 
-.. automodule:: tfw
+.. automodule:: tfw.event_handler_base
 
 .. autoclass:: EventHandlerBase
     :members:
 
-.. autoclass:: TriggeredEventHandler
+.. autoclass:: FSMAwareEventHandler
+    :members:
+
+.. autoclass:: BroadcastingEventHandler
     :members:

docs/source/foundations/fsms.rst

@@ -3,10 +3,13 @@ FSM base classes
 
 Subclass these to create an FSM that fits your tutorial/challenge.
 
-.. automodule:: tfw
+.. automodule:: tfw.fsm
 
 .. autoclass:: FSMBase
     :members:
 
 .. autoclass:: LinearFSM
     :members:
+
+.. autoclass:: YamlFSM
+    :members:

docs/source/index.rst

@@ -36,6 +36,16 @@ These are pre-written components for you to use, such as our IDE, terminal or co
 
     components/*
 
+Utility
+-------
+
+These are useful decorators, mixins and helpers to make common dev tasks easier.
+
+.. toctree::
+    :glob:
+
+    utility/*
+
 
 Indices and tables
 ==================

docs/source/networking/networking.rst

@@ -6,7 +6,7 @@ Networking
 .. autoclass:: TFWServerConnector
     :members:
 
-.. automodule:: tfw.networking.event_handlers
+.. automodule:: tfw.networking.event_handlers.server_connector
 
 .. autoclass:: ServerUplinkConnector
     :members:
@@ -15,3 +15,8 @@ Networking
 
 .. autoclass:: MessageSender
     :members:
+
+.. automodule:: tfw.networking.fsm_aware
+
+.. autoclass:: FSMAware
+    :members:

docs/source/utility/decorators.rst

@@ -0,0 +1,10 @@
+TFW decorators
+--------------
+
+.. automodule:: tfw.decorators.rate_limiter
+
+.. autoclass:: RateLimiter
+    :members:
+
+.. autoclass:: AsyncRateLimiter
+    :members:

lib/tao/__init__.py

@@ -1,2 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.

lib/tao/config/__init__.py

@@ -1,4 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .envvars import TAOENV

lib/tao/config/envvars.py

@@ -1,6 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from envvars import LazyEnvironment
-
-TAOENV = LazyEnvironment('AVATAO_', 'taoenvtuple').environment

lib/tfw/__init__.py

@@ -1,7 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .event_handler_base import EventHandlerBase, TriggeredEventHandler, BroadcastingEventHandler
-from .fsm_base import FSMBase
-from .linear_fsm import LinearFSM
-from .yaml_fsm import YamlFSM

lib/tfw/components/__init__.py

@@ -1,11 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .directory_monitoring_event_handler import DirectoryMonitoringEventHandler
-from .process_managing_event_handler import ProcessManagingEventHandler
-from .terminal_event_handler import TerminalEventHandler
-from .ide_event_handler import IdeEventHandler
-from .history_monitor import HistoryMonitor, BashMonitor, GDBMonitor
-from .terminal_commands import TerminalCommands
-from .log_monitoring_event_handler import LogMonitoringEventHandler
-from .fsm_managing_event_handler import FSMManagingEventHandler

lib/tfw/components/directory_monitor.py

@@ -1,81 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from functools import wraps
-
-from watchdog.events import FileSystemEventHandler as FileSystemWatchdogEventHandler
-
-from tfw.networking.event_handlers import ServerUplinkConnector
-from tfw.decorators import RateLimiter
-from tfw.mixins import ObserverMixin
-
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class DirectoryMonitor(ObserverMixin):
-    def __init__(self, ide_key, directories):
-        self.eventhandler = IdeReloadWatchdogEventHandler(ide_key)
-        for directory in directories:
-            self.observer.schedule(self.eventhandler, directory, recursive=True)
-
-        self.pause, self.resume = self.eventhandler.pause, self.eventhandler.resume
-
-    @property
-    def ignore(self):
-        return self.eventhandler.ignore
-
-    @ignore.setter
-    def ignore(self, value):
-        self.eventhandler.ignore = value if value >= 0 else 0
-
-    @property
-    def pauser(self):
-        return DirectoryMonitor.Pauser(self)
-
-    class Pauser:
-        def __init__(self, directory_monitor):
-            self.directorymonitor = directory_monitor
-        def __enter__(self):
-            self.directorymonitor.pause()
-        def __exit__(self, exc_type, exc_val, exc_tb):
-            self.directorymonitor.resume()
-
-
-class IdeReloadWatchdogEventHandler(FileSystemWatchdogEventHandler):
-    def __init__(self, ide_key):
-        super().__init__()
-        self.ide_key = ide_key
-        self.uplink = ServerUplinkConnector()
-        self._paused = False
-        self.ignore = 0
-
-    def pause(self):
-        self._paused = True
-
-    def resume(self):
-        self._paused = False
-
-    @RateLimiter(rate_per_second=2)
-    def on_modified(self, event):
-        if self._paused:
-            return
-        if self.ignore > 0:
-            self.ignore = self.ignore - 1
-            return
-        LOG.debug(event)
-        self.uplink.send({
-            'key': self.ide_key,
-            'data': {'command': 'reload'}
-        })
-
-
-def with_monitor_paused(fun):
-    @wraps(fun)
-    def wrapper(self, *args, **kwargs):
-        if self.monitor:
-            with self.monitor.pauser:
-                return fun(self, *args, **kwargs)
-        return fun(self, *args, **kwargs)
-    return wrapper

lib/tfw/components/directory_monitoring_event_handler.py

@@ -1,70 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from os.path import isdir, exists
-
-from tfw import EventHandlerBase
-from tfw.config.logs import logging
-from tfw.mixins import MonitorManagerMixin
-from .directory_monitor import DirectoryMonitor
-
-LOG = logging.getLogger(__name__)
-
-
-class DirectoryMonitoringEventHandler(EventHandlerBase, MonitorManagerMixin):
-    def __init__(self, key, directory):
-        super().__init__(key)
-        self._directory = directory
-        MonitorManagerMixin.__init__(
-            self,
-            DirectoryMonitor,
-            key,
-            self._directory
-        )
-
-        self.commands = {
-            'pause':     self.pause,
-            'resume':    self.resume,
-            'ignore':    self.ignore,
-            'selectdir': self.selectdir
-        }
-
-    @property
-    def directory(self):
-        return self._directory
-
-    @directory.setter
-    def directory(self, directory):
-        if not exists(directory) or not isdir(directory):
-            raise EnvironmentError('No such directory!')
-        self._directory = directory
-
-    def handle_event(self, message):
-        try:
-            message['data'] = self.commands[message['data']['command']](message['data'])
-            return message
-        except KeyError:
-            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
-
-    def pause(self, data):
-        self.monitor.pause()
-        return data
-
-    def resume(self, data):
-        self.monitor.resume()
-        return data
-
-    def ignore(self, data):
-        self.monitor.ignore += data['ignore']
-        return data
-
-    def selectdir(self, data):
-        try:
-            self.directory = data['directory']
-            self.reload_monitor()
-            return data
-        except EnvironmentError:
-            LOG.error('Failed to switch directory!')
-
-    def cleanup(self):
-        self.monitor.stop()

lib/tfw/components/fsm_managing_event_handler.py

@@ -1,56 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tfw import BroadcastingEventHandler
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class FSMManagingEventHandler(BroadcastingEventHandler):
-    def __init__(self, key, fsm_type):
-        super().__init__(key)
-        self.fsm = fsm_type()
-        self._fsm_updater = FSMUpdater(self.fsm)
-
-        self.command_handlers = {
-            'trigger': self.handle_trigger,
-            'update':  self.handle_update
-        }
-
-    def handle_event(self, message):
-        try:
-            data = message['data']
-            message['data'] = self.command_handlers[data['command']](data)
-            return message
-        except KeyError:
-            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
-
-    def handle_trigger(self, data):
-        self.fsm.step(data['value'])
-        return self.with_fsm_update(data)
-
-    def with_fsm_update(self, data):
-        return {
-            **data,
-            **self._fsm_updater.get_fsm_state_and_transitions()
-        }
-
-    def handle_update(self, data):
-        return self.with_fsm_update(data)
-
-
-class FSMUpdater:
-    def __init__(self, fsm):
-        self.fsm = fsm
-
-    def get_fsm_state_and_transitions(self):
-        state = self.fsm.state
-        valid_transitions = [
-            {'trigger': trigger}
-            for trigger in self.fsm.get_triggers(self.fsm.state)
-        ]
-        return {
-            'current_state': state,
-            'valid_transitions': valid_transitions
-        }

lib/tfw/components/ide_event_handler.py

@@ -1,254 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from os.path import isfile, join, relpath, exists, isdir, realpath
-from glob import glob
-from fnmatch import fnmatchcase
-from collections import Iterable
-
-from tfw import EventHandlerBase
-from tfw.mixins import MonitorManagerMixin
-from tfw.config.logs import logging
-from .directory_monitor import DirectoryMonitor
-
-LOG = logging.getLogger(__name__)
-
-
-class FileManager:  # pylint: disable=too-many-instance-attributes
-    def __init__(self, working_directory, allowed_directories, selected_file=None, exclude=None):
-        self._exclude, self.exclude = None, exclude
-        self._allowed_directories, self.allowed_directories = None, allowed_directories
-        self._workdir, self.workdir = None, working_directory
-        self._filename, self.filename = None, selected_file or self.files[0]
-
-    @property
-    def exclude(self):
-        return self._exclude
-
-    @exclude.setter
-    def exclude(self, exclude):
-        if exclude is None:
-            return
-        if not isinstance(exclude, Iterable):
-            raise TypeError('Exclude must be Iterable!')
-        self._exclude = exclude
-
-    @property
-    def workdir(self):
-        return self._workdir
-
-    @workdir.setter
-    def workdir(self, directory):
-        if not exists(directory) or not isdir(directory):
-            raise EnvironmentError(f'"{directory}" is not a directory!')
-        if not self._is_in_allowed_dir(directory):
-            raise EnvironmentError(f'Directory "{directory}" is not allowed!')
-        self._workdir = directory
-
-    @property
-    def allowed_directories(self):
-        return self._allowed_directories
-
-    @allowed_directories.setter
-    def allowed_directories(self, directories):
-        self._allowed_directories = directories
-
-    @property
-    def filename(self):
-        return self._filename
-
-    @filename.setter
-    def filename(self, filename):
-        if filename not in self.files:
-            raise EnvironmentError('No such file in workdir!')
-        self._filename = filename
-
-    @property
-    def files(self):
-        return [
-            self._relpath(file)
-            for file in glob(join(self._workdir, '**/*'), recursive=True)
-            if isfile(file)
-            and self._is_in_allowed_dir(file)
-            and not self._is_blacklisted(file)
-        ]
-
-    @property
-    def file_contents(self):
-        with open(self._filepath(self.filename), 'r', errors='surrogateescape') as ifile:
-            return ifile.read()
-
-    @file_contents.setter
-    def file_contents(self, value):
-        with open(self._filepath(self.filename), 'w', errors='surrogateescape') as ofile:
-            ofile.write(value)
-
-    def _is_in_allowed_dir(self, path):
-        return any(
-            realpath(path).startswith(allowed_dir)
-            for allowed_dir in self.allowed_directories
-        )
-
-    def _is_blacklisted(self, file):
-        return any(
-            fnmatchcase(file, blacklisted)
-            for blacklisted in self.exclude
-        )
-
-    def _filepath(self, filename):
-        return join(self._workdir, filename)
-
-    def _relpath(self, filename):
-        return relpath(self._filepath(filename), start=self._workdir)
-
-
-class IdeEventHandler(EventHandlerBase, MonitorManagerMixin):
-    # pylint: disable=too-many-arguments
-    """
-    Event handler implementing the backend of our browser based IDE.
-    By default all files in the directory specified in __init__ are displayed
-    on the fontend. Note that this is a stateful component.
-
-    When any file in the selected directory changes they are automatically refreshed
-    on the frontend (this is done by listening to inotify events).
-
-    This EventHandler accepts messages that have a data['command'] key specifying
-    a command to be executed.
-
-    The API of each command is documented in their respective handler.
-    """
-    def __init__(self, key, directory, allowed_directories, selected_file=None, exclude=None):
-        """
-        :param key: the key this instance should listen to
-        :param directory: working directory which the EventHandler should serve files from
-        :param allowed_directories: list of directories that can be switched to using selectdir
-        :param selected_file: file that is selected by default
-        :param exclude: list of filenames that should not appear between files (for .o, .pyc, etc.)
-        """
-        super().__init__(key)
-        try:
-            self.filemanager = FileManager(
-                allowed_directories=allowed_directories,
-                working_directory=directory,
-                selected_file=selected_file,
-                exclude=exclude
-            )
-        except IndexError:
-            raise EnvironmentError(
-                f'No file(s) in IdeEventHandler working_directory "{directory}"!'
-            )
-
-        MonitorManagerMixin.__init__(
-            self,
-            DirectoryMonitor,
-            self.key,
-            self.filemanager.allowed_directories
-        )
-
-        self.commands = {
-            'read':      self.read,
-            'write':     self.write,
-            'select':    self.select,
-            'selectdir': self.select_dir,
-            'exclude':   self.exclude
-        }
-
-    def read(self, data):
-        """
-        Read the currently selected file.
-
-        :return dict: message with the contents of the file in data['content']
-        """
-        try:
-            data['content'] = self.filemanager.file_contents
-        except PermissionError:
-            data['content'] = 'You have no permission to open that file :('
-        except FileNotFoundError:
-            data['content'] = 'This file was removed :('
-        except Exception: # pylint: disable=broad-except
-            data['content'] = 'Failed to read file :('
-        return data
-
-    def write(self, data):
-        """
-        Overwrites a file with the desired string.
-
-        :param data: TFW message data containing key 'content'
-                     (new file content)
-
-        """
-        self.monitor.ignore = self.monitor.ignore + 1
-        try:
-            self.filemanager.file_contents = data['content']
-        except Exception: # pylint: disable=broad-except
-            LOG.exception('Error writing file!')
-        del data['content']
-        return data
-
-    def select(self, data):
-        """
-        Selects a file from the current directory.
-
-        :param data: TFW message data containing 'filename'
-                     (name of file to select relative to the current directory)
-        """
-        try:
-            self.filemanager.filename = data['filename']
-        except EnvironmentError:
-            LOG.exception('Failed to select file "%s"', data['filename'])
-        return data
-
-    def select_dir(self, data):
-        """
-        Select a new working directory to display files from.
-
-        :param data: TFW message data containing 'directory'
-                     (absolute path of diretory to select.
-                     must be a path whitelisted in
-                     self.allowed_directories)
-        """
-        try:
-            self.filemanager.workdir = data['directory']
-            self.reload_monitor()
-            try:
-                self.filemanager.filename = self.filemanager.files[0]
-                self.read(data)
-            except IndexError:
-                data['content'] = 'No files in this directory :('
-        except EnvironmentError as err:
-            LOG.error('Failed to select directory "%s". Reason: %s', data['directory'], str(err))
-        return data
-
-    def exclude(self, data):
-        """
-        Overwrite list of excluded files
-
-        :param data: TFW message data containing 'exclude'
-                     (list of unix-style filename patterns to be excluded,
-                     e.g.: ["\*.pyc", "\*.o")
-        """
-        try:
-            self.filemanager.exclude = list(data['exclude'])
-        except TypeError:
-            LOG.error('Exclude must be Iterable!')
-        return data
-
-    def attach_fileinfo(self, data):
-        """
-        Basic information included in every response to the frontend.
-        """
-        data['filename'] = self.filemanager.filename
-        data['files'] = self.filemanager.files
-        data['directory'] = self.filemanager.workdir
-
-    def handle_event(self, message):
-        try:
-            data = message['data']
-            message['data'] = self.commands[data['command']](data)
-            self.attach_fileinfo(data)
-            return message
-        except KeyError:
-            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
-
-    def cleanup(self):
-        self.monitor.stop()

lib/tfw/components/log_monitor.py

@@ -1,56 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-import logging
-from os.path import dirname
-
-from watchdog.events import PatternMatchingEventHandler as PatternMatchingWatchdogEventHandler
-
-from tfw.networking.event_handlers import ServerUplinkConnector
-from tfw.decorators import RateLimiter
-from tfw.mixins import ObserverMixin, SupervisorLogMixin
-
-
-class LogMonitor(ObserverMixin):
-    def __init__(self, process_name, log_tail=0):
-        self.prevent_log_recursion()
-        event_handler = SendLogWatchdogEventHandler(
-            process_name,
-            log_tail=log_tail
-        )
-        self.observer.schedule(
-            event_handler,
-            event_handler.path
-        )
-
-    @staticmethod
-    def prevent_log_recursion():
-        # This is done to prevent inotify event logs triggering themselves (infinite log recursion)
-        logging.getLogger('watchdog.observers.inotify_buffer').propagate = False
-
-
-class SendLogWatchdogEventHandler(PatternMatchingWatchdogEventHandler, SupervisorLogMixin):
-    def __init__(self, process_name, log_tail=0):
-        self.process_name = process_name
-        self.procinfo = self.supervisor.getProcessInfo(self.process_name)
-        super().__init__([
-            self.procinfo['stdout_logfile'],
-            self.procinfo['stderr_logfile']
-        ])
-        self.uplink = ServerUplinkConnector()
-        self.log_tail = log_tail
-
-    @property
-    def path(self):
-        return dirname(self.procinfo['stdout_logfile'])
-
-    @RateLimiter(rate_per_second=5)
-    def on_modified(self, event):
-        self.uplink.send({
-            'key': 'processlog',
-            'data': {
-                'command': 'new_log',
-                'stdout': self.read_stdout(self.process_name, tail=self.log_tail),
-                'stderr': self.read_stderr(self.process_name, tail=self.log_tail)
-            }
-        })

lib/tfw/components/log_monitoring_event_handler.py

@@ -1,67 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tfw import EventHandlerBase
-from tfw.mixins import MonitorManagerMixin
-from tfw.config.logs import logging
-from .log_monitor import LogMonitor
-
-LOG = logging.getLogger(__name__)
-
-
-class LogMonitoringEventHandler(EventHandlerBase, MonitorManagerMixin):
-    """
-    Monitors the output of a supervisor process (stdout, stderr) and
-    sends the results to the frontend.
-
-    Accepts messages that have a data['command'] key specifying
-    a command to be executed.
-
-    The API of each command is documented in their respective handler.
-    """
-    def __init__(self, key, process_name, log_tail=0):
-        super().__init__(key)
-        self.process_name = process_name
-        self.log_tail = log_tail
-        MonitorManagerMixin.__init__(
-            self,
-            LogMonitor,
-            self.process_name,
-            self.log_tail
-        )
-
-        self.command_handlers = {
-            'process_name': self.handle_process_name,
-            'log_tail':     self.handle_log_tail
-        }
-
-    def handle_event(self, message):
-        try:
-            data = message['data']
-            self.command_handlers[data['command']](data)
-            self.reload_monitor()
-        except KeyError:
-            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
-
-    def handle_process_name(self, data):
-        """
-        Changes the monitored process.
-
-        :param data: TFW message data containing 'value'
-                     (name of the process to monitor)
-        """
-        self.set_monitor_args(data['value'], self.log_tail)
-
-    def handle_log_tail(self, data):
-        """
-        Sets tail length of the log the monitor will send
-        to the frontend (the monitor will send back the last
-        'value' characters of the log).
-
-        :param data: TFW message data containing 'value'
-                     (new tail length)
-        """
-        self.set_monitor_args(self.process_name, data['value'])
-
-    def cleanup(self):
-        self.monitor.stop()

lib/tfw/components/process_managing_event_handler.py

@@ -1,65 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from xmlrpc.client import Fault as SupervisorFault
-
-from tfw import EventHandlerBase
-from tfw.mixins import SupervisorMixin, SupervisorLogMixin
-from tfw.config.logs import logging
-from .directory_monitor import with_monitor_paused
-
-LOG = logging.getLogger(__name__)
-
-
-class ProcessManager(SupervisorMixin, SupervisorLogMixin):
-    def __init__(self):
-        self.commands = {
-            'start':   self.start_process,
-            'stop':    self.stop_process,
-            'restart': self.restart_process
-        }
-
-    def __call__(self, command, process_name):
-        return self.commands[command](process_name)
-
-
-class ProcessManagingEventHandler(EventHandlerBase):
-    """
-    Event handler that can manage processes managed by supervisor.
-
-    This EventHandler accepts messages that have a data['command'] key specifying
-    a command to be executed.
-    Every message must contain a data['process_name'] field with the name of the
-    process to manage. This is the name specified in supervisor config files like so:
-    [program:someprogram]
-
-    Commands available: start, stop, restart, readlog
-    (the names are as self-documenting as it gets)
-    """
-    def __init__(self, key, dirmonitor=None, log_tail=0):
-        super().__init__(key)
-        self.key = key
-        self.monitor = dirmonitor
-        self.processmanager = ProcessManager()
-        self.log_tail = log_tail
-
-    @with_monitor_paused
-    def handle_event(self, message):
-        try:
-            data = message['data']
-            try:
-                self.processmanager(data['command'], data['process_name'])
-            except SupervisorFault as fault:
-                message['data']['error'] = fault.faultString
-            finally:
-                message['data']['stdout'] = self.processmanager.read_stdout(
-                    data['process_name'],
-                    self.log_tail
-                )
-                message['data']['stderr'] = self.processmanager.read_stderr(
-                    data['process_name'],
-                    self.log_tail
-                )
-            return message
-        except KeyError:
-            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)

lib/tfw/components/terminal_event_handler.py

@@ -1,87 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tfw import EventHandlerBase
-from tfw.config import TFWENV
-from tfw.config.logs import logging
-from tao.config import TAOENV
-from .terminado_mini_server import TerminadoMiniServer
-
-LOG = logging.getLogger(__name__)
-
-
-class TerminalEventHandler(EventHandlerBase):
-    """
-    Event handler responsible for managing terminal sessions for frontend xterm
-    sessions to connect to. You need to instanciate this in order for frontend
-    terminals to work.
-
-    This EventHandler accepts messages that have a data['command'] key specifying
-    a command to be executed.
-    The API of each command is documented in their respective handler.
-    """
-    def __init__(self, key, monitor):
-        """
-        :param key: key this EventHandler listens to
-        :param monitor: tfw.components.HistoryMonitor instance to read command history from
-        """
-        super().__init__(key)
-        self.working_directory = TFWENV.TERMINADO_DIR
-        self._historymonitor = monitor
-        bash_as_user_cmd = ['sudo', '-u', TAOENV.USER, 'bash']
-
-        self.terminado_server = TerminadoMiniServer(
-            '/terminal',
-            TFWENV.TERMINADO_PORT,
-            TFWENV.TERMINADO_WD,
-            bash_as_user_cmd
-        )
-
-        self.commands = {
-            'write': self.write,
-            'read': self.read
-        }
-
-        if self._historymonitor:
-            self._historymonitor.watch()
-        self.terminado_server.listen()
-
-    @property
-    def historymonitor(self):
-        return self._historymonitor
-
-    def handle_event(self, message):
-        LOG.debug('TerminadoEventHandler received event: %s', message)
-        try:
-            data = message['data']
-            message['data'] = self.commands[data['command']](data)
-            return message
-        except KeyError:
-            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
-
-    def write(self, data):
-        """
-        Writes a string to the terminal session (on the pty level).
-        Useful for pre-typing and executing commands for the user.
-
-        :param data: TFW message data containing 'value'
-                     (command to be written to the pty)
-        """
-        self.terminado_server.pty.write(data['value'])
-
-    def read(self, data):
-        """
-        Reads the history of commands executed.
-
-        :param data: TFW message data containing 'count'
-                     (the number of history elements to return)
-        :return dict: message with list of commands in data['history']
-        """
-        data['count'] = int(data.get('count', 1))
-        if self.historymonitor:
-            data['history'] = self.historymonitor.history[-data['count']:]
-        return data
-
-    def cleanup(self):
-        if self.historymonitor:
-            self.historymonitor.stop()

lib/tfw/config/__init__.py

@@ -1,4 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .envvars import TFWENV

lib/tfw/config/envvars.py

@@ -1,6 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from envvars import LazyEnvironment
-
-TFWENV = LazyEnvironment('TFW_', 'tfwenvtuple').environment

lib/tfw/config/logs.py

@@ -1,6 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-import logging
-
-logging.basicConfig(level=logging.DEBUG)

lib/tfw/decorators/__init__.py

@@ -1,5 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .rate_limiter import RateLimiter
-from .lazy_property import lazy_property

lib/tfw/decorators/rate_limiter.py

@@ -1,25 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from functools import wraps
-from time import time, sleep
-
-
-class RateLimiter:
-    def __init__(self, rate_per_second):
-        self.min_interval = 1 / float(rate_per_second)
-        self.last_call = time()
-
-    def __call__(self, fun):
-        @wraps(fun)
-        def wrapper(*args, **kwargs):
-            self._limit_rate()
-            fun(*args, **kwargs)
-        return wrapper
-
-    def _limit_rate(self):
-        since_last_call = time() - self.last_call
-        to_next_call = self.min_interval - since_last_call
-        self.last_call = time()
-        if to_next_call > 0:
-            sleep(to_next_call)

lib/tfw/event_handler_base.py

@@ -1,146 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from abc import ABC, abstractmethod
-from json import dumps
-from hashlib import md5
-
-from tfw.networking.event_handlers import ServerConnector
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class EventHandlerBase(ABC):
-    """
-    Abstract base class for all Python based EventHandlers. Useful implementation template
-    for other languages.
-
-    Derived classes must implement the handle_event() method
-    """
-    def __init__(self, key):
-        self.server_connector = ServerConnector()
-        self.key = key
-        self.subscribe(self.key, 'reset')
-        self.server_connector.register_callback(self.event_handler_callback)
-
-    def event_handler_callback(self, message):
-        """
-        Callback that is invoked when receiving a message.
-        Dispatches messages to handler methods and sends
-        a response back in case the handler returned something.
-        This is subscribed in __init__().
-        """
-        response = self.dispatch_handling(message)
-        if response:
-            self.server_connector.send(response)
-
-    def dispatch_handling(self, message):
-        """
-        Used to dispatch messages to their specific handlers.
-
-        :param message: the message received
-        :returns: the message to send back
-        """
-        if message['key'] != 'reset':
-            return self.handle_event(message)
-        return self.handle_reset(message)
-
-    @abstractmethod
-    def handle_event(self, message):
-        """
-        Abstract method that implements the handling of messages.
-
-        :param message: the message received
-        :returns: the message to send back
-        """
-        raise NotImplementedError
-
-    def handle_reset(self, message):
-        # pylint: disable=unused-argument,no-self-use
-        """
-        Usually 'reset' events receive some sort of special treatment.
-
-        :param message: the message received
-        :returns: the message to send back
-        """
-        return None
-
-    def subscribe(self, *keys):
-        """
-        Subscribe this EventHandler to receive events for given keys.
-        Note that you can subscribe to the same key several times in which
-        case you will need to unsubscribe multiple times in order to stop
-        receiving events.
-        
-        :param keys: list of keys to subscribe to
-        """
-        for key in keys:
-            self.server_connector.subscribe(key)
-
-    def unsubscribe(self, *keys):
-        """
-        Unsubscribe this eventhandler from the given keys.
-
-        :param keys: list of keys to unsubscribe from
-        """
-        for key in keys:
-            self.server_connector.unsubscribe(key)
-
-    def cleanup(self):
-        """
-        Perform cleanup actions such as releasing database
-        connections and stuff like that.
-        """
-        pass
-
-
-class TriggeredEventHandler(EventHandlerBase, ABC):
-    # pylint: disable=abstract-method
-    """
-    Abstract base class for EventHandlers which are only triggered in case
-    TFWServer has successfully triggered an FSM step defined in __init__.
-    """
-    def __init__(self, key, trigger):
-        super().__init__(key)
-        self.trigger = trigger
-
-    def dispatch_handling(self, message):
-        if message.get('trigger') == self.trigger:
-            return super().dispatch_handling(message)
-        return None
-
-
-class BroadcastingEventHandler(EventHandlerBase, ABC):
-    # pylint: disable=abstract-method
-    """
-    Abstract base class for EventHandlers which broadcast responses
-    and intelligently ignore their own broadcasted messages they receive.
-    """
-    def __init__(self, key):
-        super().__init__(key)
-        self.own_message_hashes = []
-
-    def event_handler_callback(self, message):
-        message_hash = self.hash_message(message)
-
-        if message_hash in self.own_message_hashes:
-            self.own_message_hashes.remove(message_hash)
-            return
-
-        response = self.dispatch_handling(message)
-        if response:
-            self.own_message_hashes.append(self.hash_message(response))
-            self.server_connector.send(self.make_broadcast_message(response))
-
-    @staticmethod
-    def hash_message(message):
-        message_bytes = dumps(message, sort_keys=True).encode()
-        return md5(message_bytes).hexdigest()
-
-    @staticmethod
-    def make_broadcast_message(message):
-        return {
-            'key': 'broadcast',
-            'data': message
-        }

lib/tfw/linear_fsm.py

@@ -1,29 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .fsm_base import FSMBase
-
-
-class LinearFSM(FSMBase):
-    # pylint: disable=anomalous-backslash-in-string
-    """
-    This is a state machine for challenges with linear progression, consisting of
-    a number of steps specified in the constructor. It automatically sets up 2
-    actions (triggers) between states as such:
-    (0) --  step_1  --> (1) --  step_2  --> (2) --  step_3  --> (3) ... and so on
-    """
-    def __init__(self, number_of_steps):
-        self.states = list(map(str, range(number_of_steps)))
-        self.transitions = []
-        for index in self.states[:-1]:
-            self.transitions.append({
-                'trigger': f'step_{int(index)+1}',
-                'source': index,
-                'dest': str(int(index)+1)
-            })
-            self.transitions.append({
-                'trigger': 'step_next',
-                'source': index,
-                'dest': str(int(index)+1)
-            })
-        super(LinearFSM, self).__init__()

lib/tfw/mixins/__init__.py

@@ -1,7 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .supervisor_mixin import SupervisorMixin, SupervisorLogMixin
-from .callback_mixin import CallbackMixin
-from .observer_mixin import ObserverMixin
-from .monitor_manager_mixin import MonitorManagerMixin

lib/tfw/mixins/monitor_manager_mixin.py

@@ -1,30 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class MonitorManagerMixin:
-    def __init__(self, monitor_type, *monitor_args):
-        self._monitor_type = monitor_type
-        self._monitor = None
-        self.monitor_args = monitor_args
-        self.reload_monitor()
-
-    @property
-    def monitor(self):
-        return self._monitor
-
-    def set_monitor_args(self, *monitor_args):
-        self.monitor_args = monitor_args
-
-    def reload_monitor(self):
-        if self._monitor:
-            try:
-                self._monitor.stop()
-            except KeyError:
-                LOG.debug('Working directory was removed – ignoring...')
-        self._monitor = self._monitor_type(*self.monitor_args)
-        self._monitor.watch()   # This runs on a separate thread

lib/tfw/mixins/observer_mixin.py

@@ -1,19 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from watchdog.observers import Observer
-
-from tfw.decorators import lazy_property
-
-
-class ObserverMixin:
-    @lazy_property
-    def observer(self):
-        return Observer()
-
-    def watch(self):
-        self.observer.start()
-
-    def stop(self):
-        self.observer.stop()
-        self.observer.join()

lib/tfw/networking/__init__.py

@@ -1,9 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .serialization import serialize_tfw_msg, deserialize_tfw_msg, with_deserialize_tfw_msg
-from .zmq_connector_base import ZMQConnectorBase
-# from .controller_connector import ControllerConnector # TODO: readd once controller stuff is resolved
-from .message_sender import MessageSender
-from .event_handlers.server_connector import ServerUplinkConnector as TFWServerConnector
-from .server.tfw_server import TFWServer

lib/tfw/networking/controller_connector.py

@@ -1,18 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-import zmq
-from zmq.eventloop.zmqstream import ZMQStream
-
-from tfw.config import TFWENV
-from tfw.networking import ZMQConnectorBase
-
-
-class ControllerConnector(ZMQConnectorBase):
-    def __init__(self, zmq_context=None):
-        super(ControllerConnector, self).__init__(zmq_context)
-        self._zmq_rep_socket = self._zmq_context.socket(zmq.REP)
-        self._zmq_rep_socket.connect(f'tcp://localhost:{TFWENV.CONTROLLER_PORT}')
-        self._zmq_rep_stream = ZMQStream(self._zmq_rep_socket)
-
-        self.register_callback = self._zmq_rep_stream.on_recv_stream

lib/tfw/networking/event_handlers/__init__.py

@@ -1,4 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .server_connector import ServerConnector, ServerUplinkConnector, ServerDownlinkConnector

lib/tfw/networking/event_handlers/server_connector.py

@@ -1,65 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from functools import partial
-
-import zmq
-from zmq.eventloop.zmqstream import ZMQStream
-
-from tfw.networking import serialize_tfw_msg, with_deserialize_tfw_msg
-from tfw.networking import ZMQConnectorBase
-from tfw.config import TFWENV
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class ServerDownlinkConnector(ZMQConnectorBase):
-    def __init__(self, zmq_context=None):
-        super(ServerDownlinkConnector, self).__init__(zmq_context)
-        self._zmq_sub_socket = self._zmq_context.socket(zmq.SUB)
-        self._zmq_sub_socket.connect(f'tcp://localhost:{TFWENV.PUBLISHER_PORT}')
-        self._zmq_sub_stream = ZMQStream(self._zmq_sub_socket)
-
-        self.subscribe = partial(self._zmq_sub_socket.setsockopt_string, zmq.SUBSCRIBE)
-        self.unsubscribe = partial(self._zmq_sub_socket.setsockopt_string, zmq.UNSUBSCRIBE)
-
-    def register_callback(self, callback):
-        callback = with_deserialize_tfw_msg(callback)
-        self._zmq_sub_stream.on_recv(callback)
-
-
-class ServerUplinkConnector(ZMQConnectorBase):
-    """
-    Class capable of sending messages to the TFW server and event handlers.
-    """
-    def __init__(self, zmq_context=None):
-        super(ServerUplinkConnector, self).__init__(zmq_context)
-        self._zmq_push_socket = self._zmq_context.socket(zmq.PUSH)
-        self._zmq_push_socket.connect(f'tcp://localhost:{TFWENV.RECEIVER_PORT}')
-
-    def send_to_eventhandler(self, message):
-        """
-        Send a message to an event handler.
-        This envelopes the desired message in the 'data' field of the message to
-        TFWServer, which will mirror it to event handlers.
-
-        :param message: JSON message you want to send
-        :param message['key']: key of event handler you want to address
-        """
-        nested_message = {'key': message['key'], 'data': message.pop('data')}
-        message['key'] = 'mirror'
-        message['data'] = nested_message
-        self.send(message)
-
-    def send(self, message):
-        """
-        Send a message to the TFW server
-
-        :param message: JSON message you want to send
-        """
-        self._zmq_push_socket.send_multipart(serialize_tfw_msg(message))
-
-
-class ServerConnector(ServerUplinkConnector, ServerDownlinkConnector):
-    pass

lib/tfw/networking/message_sender.py

@@ -1,46 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tfw.networking.event_handlers import ServerUplinkConnector
-
-
-class MessageSender:
-    """
-    Provides mechanisms to send messages to our frontend messaging component.
-    """
-    def __init__(self):
-        self.server_connector = ServerUplinkConnector()
-        self.key = 'message'
-        self.queue_key = 'queueMessages'
-
-    def send(self, originator, message):
-        """
-        Sends a message.
-        :param originator: name of sender to be displayed on the frontend
-        :param message: message to send
-        """
-        data = {
-            'originator': originator,
-            'message': message
-        }
-        self.server_connector.send({
-            'key': self.key,
-            'data': data
-        })
-
-    def queue_messages(self, originator, messages):
-        """
-        Queues a list of messages to be displayed in a chatbot-like manner.
-        :param originator: name of sender to be displayed on the frontend
-        :param messages: list of messages to queue
-        """
-        data = {
-            'messages': [
-                {'message': message, 'originator': originator}
-                for message in messages
-            ]
-        }
-        self.server_connector.send({
-            'key': self.queue_key,
-            'data': data
-        })

lib/tfw/networking/server/__init__.py

@@ -1,6 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from .event_handler_connector import EventHandlerConnector, EventHandlerUplinkConnector, EventHandlerDownlinkConnector
-from .tfw_server import TFWServer
-# from .controller_responder import ControllerResponder  # TODO: readd once controller stuff is resolved

lib/tfw/networking/server/controller_responder.py

@@ -1,38 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tfw.networking import deserialize_all, serialize_all, ControllerConnector
-
-
-class ControllerResponder:
-    def __init__(self, fsm):
-        self.fsm = fsm
-        self.token = None
-        self.controller_connector = ControllerConnector()
-        self.controller_connector.register_callback(self.handle_controller_request)
-        self.controller_request_handlers = {
-            'solution_check': self.handle_solution_check_request,
-            'test': self.handle_test_request,
-            'token': self.handle_token_request
-        }
-
-    def handle_controller_request(self, stream, msg_parts):
-        key, data = deserialize_all(*msg_parts)
-        response = self.controller_request_handlers[key](data)
-        stream.send_multipart(serialize_all(self.token, response))
-
-    def handle_test_request(self, data):
-        # pylint: disable=unused-argument,no-self-use
-        return 'OK'
-
-    def handle_token_request(self, data):
-        if self.token is None:
-            self.token = data
-        return {'token': self.token}
-
-    def handle_solution_check_request(self, data):
-        # pylint: disable=unused-argument
-        return {
-            'solved': self.fsm.is_solved(),
-            'message': 'solved' if self.fsm.is_solved() else 'not solved'
-        }

lib/tfw/networking/server/event_handler_connector.py

@@ -1,39 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-import zmq
-from zmq.eventloop.zmqstream import ZMQStream
-
-from tfw.networking import ZMQConnectorBase, serialize_tfw_msg, with_deserialize_tfw_msg
-from tfw.config import TFWENV
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class EventHandlerDownlinkConnector(ZMQConnectorBase):
-    def __init__(self, zmq_context=None):
-        super(EventHandlerDownlinkConnector, self).__init__(zmq_context)
-        self._zmq_pull_socket = self._zmq_context.socket(zmq.PULL)
-        self._zmq_pull_stream = ZMQStream(self._zmq_pull_socket)
-        address = f'tcp://*:{TFWENV.RECEIVER_PORT}'
-        self._zmq_pull_socket.bind(address)
-        LOG.debug('Pull socket bound to %s', address)
-
-
-class EventHandlerUplinkConnector(ZMQConnectorBase):
-    def __init__(self, zmq_context=None):
-        super(EventHandlerUplinkConnector, self).__init__(zmq_context)
-        self._zmq_pub_socket = self._zmq_context.socket(zmq.PUB)
-        address = f'tcp://*:{TFWENV.PUBLISHER_PORT}'
-        self._zmq_pub_socket.bind(address)
-        LOG.debug('Pub socket bound to %s', address)
-
-
-class EventHandlerConnector(EventHandlerDownlinkConnector, EventHandlerUplinkConnector):
-    def register_callback(self, callback):
-        callback = with_deserialize_tfw_msg(callback)
-        self._zmq_pull_stream.on_recv(callback)
-
-    def send_message(self, message: dict):
-        self._zmq_pub_socket.send_multipart(serialize_tfw_msg(message))

lib/tfw/networking/server/tfw_server.py

@@ -1,43 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-from tornado.web import Application
-
-from tfw.networking.event_handlers import ServerUplinkConnector
-from tfw.networking.server import EventHandlerConnector
-from tfw.config.logs import logging
-from .zmq_websocket_proxy import ZMQWebSocketProxy
-
-LOG = logging.getLogger(__name__)
-
-
-class TFWServer:
-    """
-    This class handles the proxying of messages between the frontend and event handers.
-    It proxies messages from the "/ws" route to all event handlers subscribed to a ZMQ
-    SUB socket.
-    """
-    def __init__(self):
-        self._event_handler_connector = EventHandlerConnector()
-        self._uplink_connector = ServerUplinkConnector()
-
-        self.application = Application([(
-            r'/ws', ZMQWebSocketProxy,{
-                'event_handler_connector': self._event_handler_connector,
-                'message_handlers': [self.handle_trigger]
-            })]
-        )
-
-    def handle_trigger(self, message):
-        if 'trigger' in message:
-            LOG.debug('Executing handler for trigger "%s"', message.get('trigger', ''))
-            self._uplink_connector.send_to_eventhandler({
-                'key': 'fsm',
-                'data': {
-                    'command': 'trigger',
-                    'value': message.get('trigger', '')
-                }
-            })
-
-    def listen(self, port):
-        self.application.listen(port)

lib/tfw/networking/server/zmq_websocket_proxy.py

@@ -1,121 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-import json
-
-from tornado.websocket import WebSocketHandler
-
-from tfw.mixins import CallbackMixin
-from tfw.config.logs import logging
-
-LOG = logging.getLogger(__name__)
-
-
-class ZMQWebSocketProxy(WebSocketHandler):
-    instances = set()
-
-    def initialize(self, **kwargs): # pylint: disable=arguments-differ
-        self._event_handler_connector = kwargs['event_handler_connector']
-        self._message_handlers = kwargs.get('message_handlers', [])
-        self._proxy_filters = kwargs.get('proxy_filters', [])
-
-        self.proxy_eventhandler_to_websocket = TFWProxy(
-            self.send_eventhandler_message,
-            self.send_websocket_message
-        )
-        self.proxy_websocket_to_eventhandler = TFWProxy(
-            self.send_websocket_message,
-            self.send_eventhandler_message
-        )
-
-        proxies = (self.proxy_eventhandler_to_websocket, self.proxy_websocket_to_eventhandler)
-        for proxy in proxies:
-            proxy.proxy_filters.subscribe_callbacks(*self._proxy_filters)
-            proxy.proxy_callbacks.subscribe_callbacks(*self._message_handlers)
-
-    def prepare(self):
-        ZMQWebSocketProxy.instances.add(self)
-
-    def on_close(self):
-        ZMQWebSocketProxy.instances.remove(self)
-
-    def open(self, *args, **kwargs):
-        LOG.debug('WebSocket connection initiated')
-        self._event_handler_connector.register_callback(self.eventhander_callback)
-
-    def eventhander_callback(self, message):
-        """
-        Invoked on ZMQ messages from event handlers.
-        """
-        LOG.debug('Received on pull socket: %s', message)
-        self.proxy_eventhandler_to_websocket(message)
-
-    def on_message(self, message):
-        """
-        Invoked on WS messages from frontend.
-        """
-        message = json.loads(message)
-        LOG.debug('Received on WebSocket: %s', message)
-        self.proxy_websocket_to_eventhandler(message)
-
-    def send_eventhandler_message(self, message):
-        self._event_handler_connector.send_message(message)
-
-    @staticmethod
-    def send_websocket_message(message):
-        for instance in ZMQWebSocketProxy.instances:
-            instance.write_message(message)
-
-    # much secure, very cors, wow
-    def check_origin(self, origin):
-        return True
-
-
-class TFWProxy:
-    def __init__(self, to_source, to_destination):
-        self.to_source = to_source
-        self.to_destination = to_destination
-
-        self.proxy_filters = CallbackMixin()
-        self.proxy_callbacks = CallbackMixin()
-
-        self.proxy_filters.subscribe_callback(self.validate_message)
-
-        self.keyhandlers = {
-            'mirror':    self.mirror,
-            'broadcast': self.broadcast
-        }
-
-    @staticmethod
-    def validate_message(message):
-        if 'key' not in message:
-            raise ValueError('Invalid TFW message format!')
-
-    def __call__(self, message):
-        try:
-            self.proxy_filters._execute_callbacks(message)
-        except ValueError:
-            LOG.exception('Invalid TFW message received!')
-            return
-
-        self.proxy_callbacks._execute_callbacks(message)
-
-        if message['key'] not in self.keyhandlers:
-            self.to_destination(message)
-        else:
-            handler = self.keyhandlers[message['key']]
-            try:
-                handler(message)
-            except KeyError:
-                LOG.error('Invalid "%s" message format! Ignoring.', handler.__name__)
-
-    def mirror(self, message):
-        message = message['data']
-        LOG.debug('Mirroring message: %s', message)
-        self.to_source(message)
-
-    def broadcast(self, message):
-        message = message['data']
-        LOG.debug('Broadcasting message: %s', message)
-        self.to_source(message)
-        self.to_destination(message)

lib/tfw/networking/zmq_connector_base.py

@@ -1,9 +0,0 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
-import zmq
-
-
-class ZMQConnectorBase:
-    def __init__(self, zmq_context=None):
-        self._zmq_context = zmq_context or zmq.Context.instance()

lib/tfw/yaml_fsm.py

@@ -1,64 +0,0 @@
-from subprocess import Popen, run
-from functools import partial
-from contextlib import suppress
-
-import yaml
-from transitions import State
-
-from tfw import FSMBase
-
-
-class YamlFSM(FSMBase):
-    def __init__(self, config_file):
-        self.config = self.parse_config(config_file)
-        self.setup_states()
-        super().__init__()  # FSMBase.__init__() requires states
-        self.setup_transitions()
-
-    @staticmethod
-    def parse_config(config_file):
-        with open(config_file, 'r') as ifile:
-            return yaml.safe_load(ifile)
-
-    def setup_states(self):
-        self.for_config_states_and_transitions_do(self.wrap_callbacks_with_subprocess_call)
-        self.states = [State(**state) for state in self.config['states']]
-
-    def setup_transitions(self):
-        self.for_config_states_and_transitions_do(self.subscribe_and_remove_predicates)
-        for transition in self.config['transitions']:
-            self.add_transition(**transition)
-
-    def for_config_states_and_transitions_do(self, what):
-        for array in ('states', 'transitions'):
-            for json_obj in self.config[array]:
-                what(json_obj)
-
-    @staticmethod
-    def wrap_callbacks_with_subprocess_call(json_obj):
-        topatch = ('on_enter', 'on_exit', 'prepare', 'before', 'after')
-        for key in json_obj:
-            if key in topatch:
-                json_obj[key] = partial(run_command_async, json_obj[key])
-
-    def subscribe_and_remove_predicates(self, json_obj):
-        if 'predicates' in json_obj:
-            for predicate in json_obj['predicates']:
-                    self.subscribe_predicate(
-                        json_obj['trigger'],
-                        partial(
-                            command_statuscode_is_zero,
-                            predicate
-                        )
-                    )
-                
-        with suppress(KeyError):
-            json_obj.pop('predicates')
-
-
-def run_command_async(command, event):
-    Popen(command, shell=True)
-
-
-def command_statuscode_is_zero(command):
-    return run(command, shell=True).returncode == 0

nginx/components/terminal.conf

@@ -1,5 +1,5 @@
 location = /terminal {
-        proxy_pass http://127.0.0.1:${TFW_TERMINADO_PORT};
+        proxy_pass http://terminal;
         proxy_http_version 1.1;
         proxy_set_header Upgrade $http_upgrade;
         proxy_set_header Connection "upgrade";

nginx/default.conf

@@ -1,3 +1,8 @@
+upstream terminal {
+    server 127.0.0.1:${TFW_TERMINAL_PORT};
+    server 127.0.0.1:${TFW_TERMINAL_FALLBACK_PORT} backup;
+}
+
 server {
     listen ${TFW_PUBLIC_PORT};
     server_name localhost;

pytest.ini

@@ -0,0 +1,4 @@
+[pytest]
+filterwarnings =
+    ignore::DeprecationWarning:zmq
+    ignore::DeprecationWarning:watchdog

requirements.txt

@@ -1,6 +1,15 @@
-tornado==5.0
-pyzmq==17.0.0
-transitions==0.6.4
-terminado==0.8.1
-watchdog==0.8.3
-PyYAML==3.12
+tornado>=6.0.0,<7.0.0
+pyzmq>=17.0.0,<18.0.0
+transitions>=0.0.0,<1.0.0
+terminado>=0.0.0,<1.0.0
+watchdog>=0.0.0,<1.0.0
+PyYAML>=5.0.0,<6.0.0
+Jinja2>=2.0.0,<3.0.0
+cryptography>=2.0.0,<3.0.0
+python-dateutil>=2.0.0,<3.0.0
+SQLAlchemy>=1.0.0,<2.0.0
+python-dateutil>=2.0.0,<3.0.0
+pytest>=5.0.0,<6.0.0
+pylint>=2.0.0,<3.0.0
+rope>=0.0.0,<1.0.0
+pipe-io-server>=1.0.0,<2.0.0

setup.py

@@ -1,6 +1,6 @@
 from os.path import dirname, realpath, join
 
-from setuptools import setup, find_packages
+from setuptools import setup
 
 here = dirname(realpath(__file__))
 
@@ -10,20 +10,20 @@ with open(join(here, 'requirements.txt'), 'r') as ifile:
     requirements = ifile.read().splitlines()
 
 setup(
-    name = 'tfw',
-    version = version,
-    description = 'Avatao tutorial-framework',
-    url = 'https://github.com/avatao-content/baseimage-tutorial-framework',
-    author = 'Avatao.com Innovative Learning Kft.',
-    author_email = 'support@avatao.com',
-    license = 'custom',
-    packages = find_packages('lib'),
-    package_dir = {'': 'lib'},
-    install_requires = requirements,
-    extras_require = {
+    name='tfw',
+    version=version,
+    description='Avatao tutorial-framework',
+    url='https://github.com/avatao-content/baseimage-tutorial-framework',
+    author='Avatao.com Innovative Learning Kft.',
+    author_email='support@avatao.com',
+    license='custom',
+    packages=['tfw'],
+    package_dir={'tfw': 'tfw'},
+    install_requires=requirements,
+    extras_require={
         'docs': [
             'sphinx >= 1.7.0',
         ],
     },
-    zip_safe = False,
+    zip_safe=False,
 )

supervisor/components/terminal_fallback.conf

@@ -0,0 +1,4 @@
+[program:terminal_fallback]
+command=ncat -klp %(ENV_TFW_TERMINAL_FALLBACK_PORT)s
+autostart=true
+autorestart=true

supervisor/components/tfw_init.conf

@@ -0,0 +1,6 @@
+[program:tfw_init]
+user=root
+directory=/tmp
+command=bash tfw_init.sh
+autorestart=false
+startsecs=0

supervisor/components/tfw_server.conf

@@ -1,4 +1,4 @@
-[program:tfwserver]
+[program:tfw_server]
 user=root
 directory=%(ENV_TFW_SERVER_DIR)s
-command=python3 tfw_server.py
+command=python3 -u tfw_server.py

supervisor/tfw_init.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+set -euo pipefail
+
+echo "export HISTFILE=\"${TFW_HISTFILE}\"" >> /tmp/bashrc &&
+  cat /tmp/bashrc >> "/home/${AVATAO_USER}/.bashrc"
+
+if [[ -z "${HOTRELOAD-}" ]]; then
+  for dir in "${TFW_LIB_DIR}/tfw" "/etc/nginx" "/etc/supervisor"; do
+    chown -R root:root "${dir}" && chmod -R 700 "${dir}";
+  done
+fi
+
+chmod 777 "${TFW_PIPES_DIR}"
+
+rm -f bashrc requirements.txt tfw_init.sh

supervisor/tfw_server.py

@@ -1,9 +1,11 @@
 from tornado.ioloop import IOLoop
 
-from tfw.networking import TFWServer
-from tfw.config import TFWENV
+from tfw.main import TFWServer, setup_logger, setup_signal_handlers
 
 
 if __name__ == '__main__':
-    TFWServer().listen(TFWENV.WEB_PORT)
+    setup_logger(__file__)
+    TFWServer().listen()
+
+    setup_signal_handlers()
     IOLoop.instance().start()

tfw/components/frontend/__init__.py

@@ -0,0 +1,6 @@
+from .console_logs_handler import ConsoleLogsHandler
+from .frontend_proxy_handler import FrontendProxyHandler
+from .frontend_ready_handler import FrontendReadyHandler
+from .message_queue_handler import MessageQueueHandler
+from .message_sender import MessageSender
+from .frontend_config_handler import FrontendConfigHandler

tfw/components/frontend/console_logs_handler.py

@@ -0,0 +1,19 @@
+import logging
+
+LOG = logging.getLogger(__name__)
+
+
+class ConsoleLogsHandler:
+    keys = ['process.log.new']
+
+    def __init__(self, *, stream):
+        self.stream = stream
+
+    def handle_event(self, message, connector):
+        try:
+            connector.send_message({
+                'key': 'console.write',
+                'content': message[self.stream]
+            })
+        except KeyError:
+            LOG.error('Invalid %s message received: %s', self.keys, message)

tfw/components/frontend/frontend_config_handler/__init__.py

@@ -0,0 +1 @@
+from .frontend_config_handler import FrontendConfigHandler

tfw/components/frontend/frontend_config_handler/frontend_config_handler.py

@@ -0,0 +1,36 @@
+from yaml import safe_load
+
+from tfw.internals.networking import Scope
+
+
+class FrontendConfigHandler:
+    keys = ['frontend.ready']
+
+    def __init__(self, config_path):
+        self._config_path = config_path
+
+    def handle_event(self, _, connector):
+        # pylint: disable=no-self-use
+        for message in self._config_messages:
+            connector.send_message(message)
+        connector.send_message({'key': 'frontend.ready'}, scope=Scope.WEBSOCKET)
+
+    @property
+    def _config_messages(self):
+        config = safe_load(self._config_str)
+        return [
+            self._create_config_message(k, v)
+            for k, v in config.items()
+        ]
+
+    @property
+    def _config_str(self):
+        with open(self._config_path, 'r') as ifile:
+            return ifile.read()
+
+    @staticmethod
+    def _create_config_message(key, value):
+        return {
+            'key': f'frontend.{key}',
+            **value
+        }

tfw/components/frontend/frontend_config_handler/test_frontend_config_handler.py

@@ -0,0 +1,40 @@
+from textwrap import dedent
+
+from .frontend_config_handler import FrontendConfigHandler
+
+
+class MockFrontendConfigHandler(FrontendConfigHandler):
+    @property
+    def _config_str(self):
+        return dedent('''
+        cat:
+            someConfigKey: lel
+            otherStuff:    42
+        foo:
+            hey:           yaaay
+        ''')
+
+
+class MockConnector:
+    def __init__(self):
+        self.messages = []
+
+    def send_message(self, message, **_):
+        self.messages.append(message)
+
+
+def test_frontend_config_handler():
+    connector = MockConnector()
+    handler = MockFrontendConfigHandler('')
+
+    handler.handle_event({'key': 'frontend.ready'}, connector)
+    assert connector.messages[0] == {
+        'key': 'frontend.cat',
+        'someConfigKey': 'lel',
+        'otherStuff': 42
+    }
+    assert connector.messages[1] == {
+        'key': 'frontend.foo',
+        'hey': 'yaaay'
+    }
+    assert connector.messages[-1] == {'key': 'frontend.ready'}

tfw/components/frontend/frontend_proxy_handler.py

@@ -0,0 +1,34 @@
+from tfw.internals.networking import Scope
+
+from .message_storage import FrontendMessageStorage
+
+
+class FrontendProxyHandler:
+    keys = ['console', 'dashboard', 'frontend', 'message', 'ide.read', 'deploy.finish']
+    type_id = 'ControlEventHandler'
+
+    def __init__(self):
+        self.connector = None
+        self._frontend_message_storage = FrontendMessageStorage()
+
+    def send_message(self, message):
+        self.connector.send_message(message, scope=Scope.WEBSOCKET)
+
+    def handle_event(self, message, _):
+        self._frontend_message_storage.save_message(message)
+        if message['key'] == 'frontend.ready':
+            self.recover_frontend()
+            return
+        if self._filter_message(message):
+            self.send_message(message)
+
+    @staticmethod
+    def _filter_message(message):
+        return not message['key'].startswith((
+            'ide',
+            'message.queue'
+        ))
+
+    def recover_frontend(self):
+        for message in self._frontend_message_storage.messages:
+            self.send_message(message)

tfw/components/frontend/frontend_ready_handler.py

@@ -0,0 +1,39 @@
+import logging
+
+from tfw.internals.crypto import KeyManager, sign_message
+
+LOG = logging.getLogger(__name__)
+
+
+class FrontendReadyHandler:
+    keys = ['frontend.ready', 'fsm.update']
+
+    def __init__(self, initial_trigger):
+        self.connector = None
+        self._auth_key = KeyManager().auth_key
+        self.initial_trigger = initial_trigger
+
+        self.commands = {
+            'frontend.ready': self.handle_ready,
+            'fsm.update': self.handle_update
+        }
+
+    def handle_event(self, message, _):
+        try:
+            self.commands[message['key']]()
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def handle_ready(self):
+        trigger = {
+            'key': 'fsm.trigger',
+            'transition': self.initial_trigger
+        }
+        sign_message(self._auth_key, trigger)
+        self.connector.send_message(trigger)
+
+    def handle_update(self):
+        self.stop()
+
+    def stop(self):
+        pass

tfw/components/frontend/message_queue_handler/__init__.py

@@ -0,0 +1 @@
+from .message_queue_handler import MessageQueueHandler

tfw/components/frontend/message_queue_handler/message_queue_handler.py

@@ -0,0 +1,90 @@
+import logging
+from time import sleep, time
+from queue import Queue, Empty
+from threading import Thread
+from contextlib import suppress
+
+LOG = logging.getLogger(__name__)
+
+
+class MessageQueueHandler:
+    keys = ['message.queue']
+    type_id = 'ControlEventHandler'
+    avg_word_len = 5
+    drain_poll_freq = 0.2
+
+    def __init__(self, wpm):
+        self.connector = None
+        self.wpm = wpm
+        self._queue = Queue()
+        self._drain_queue = Queue()
+        self._thread = Thread(target=self._dispatch_messages)
+
+        self._commands = {
+            'message.queue': self.handle_queue,
+            'message.queue.drain': self.handle_drain
+        }
+
+    def _dispatch_messages(self):
+        for message in iter(self._queue.get, None):
+            message['typing'] = not self._queue.empty()
+            self.connector.send_message(message)
+            self._sleep(self._get_sleep_time(message))
+
+    def _get_sleep_time(self, message):
+        words_per_min = message['wpm'] if 'wpm' in message else self.wpm
+        chars_per_min = self.avg_word_len * words_per_min / 60
+        return len(message['message']) / chars_per_min
+
+    def _sleep(self, seconds):
+        poll_freq = self.drain_poll_freq
+        if seconds < poll_freq:
+            poll_freq = seconds
+
+        sleep_until = time() + seconds
+        while time() < sleep_until:
+            sleep(poll_freq)
+            with suppress(Empty):
+                self._drain_queue.get(block=False)
+                self._drain()
+                break
+
+    def _drain(self):
+        with suppress(Empty):
+            while True:
+                message = self._queue.get(block=False)
+                if message is None:
+                    break
+                message['typing'] = False
+                self.connector.send_message(message)
+
+    def handle_event(self, message, _):
+        try:
+            self._commands[message['key']](message)
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def handle_queue(self, message):
+        for unpacked in self._generate_messages_from_queue(message):
+            self._queue.put(unpacked)
+
+    @staticmethod
+    def _generate_messages_from_queue(queue_message):
+        for message in queue_message['messages']:
+            yield {
+                'key': 'message.send',
+                **message
+            }
+
+    def handle_drain(self, _):
+        self._drain_queue.put(True)
+
+    def start(self):
+        self._thread.start()
+
+    def cleanup(self):
+        # clearing the queue forces the loop in
+        # _dispatch_messages to block on _queue.get
+        self._queue.queue.clear()
+        self._queue.put(None)
+        self._thread.join()

tfw/components/frontend/message_queue_handler/test_message_queue.py

@@ -0,0 +1,152 @@
+# pylint: disable=redefined-outer-name
+from time import time
+from os import urandom
+from random import randint
+from queue import Queue, Empty
+
+import pytest
+
+from .message_queue_handler import MessageQueueHandler
+
+
+class MockConnector:
+    def __init__(self):
+        self.callback = None
+        self.messages = Queue()
+        self.send_times = Queue()
+
+    def raise_event(self, message):
+        self.callback(message, self)
+
+    def send_message(self, message):
+        self.messages.put(message)
+        self.send_times.put(time())
+
+
+@pytest.fixture
+def handler():
+    class NoSleepMessageQueueHandler(MessageQueueHandler):
+        sleep_start_times = Queue()
+        sleep_seconds = Queue()
+        sleep_end_times = Queue()
+
+        def _sleep(self, seconds):
+            self.sleep_start_times.put(time())
+            self.sleep_seconds.put(seconds)
+            super()._sleep(seconds)
+            self.sleep_end_times.put(time())
+
+    handler = NoSleepMessageQueueHandler(100000)
+    handler.connector = MockConnector()
+    handler.connector.callback = handler.handle_event
+
+    handler.start()
+    yield handler
+    handler.cleanup()
+
+
+def get_message_queue(*, size=None):
+    size = randint(5, 10) if not size else size
+    return {
+        'key': 'message.queue',
+        'messages': [
+            {'originator': urandom(4).hex(), 'message': urandom(randint(10, 20)).hex()}
+            for _ in range(size)
+        ]
+    }
+
+
+def test_order(handler):
+    queue = get_message_queue()
+    handler.connector.raise_event(queue)
+    expected_messages = queue['messages']
+
+    actual_messages = []
+    for _ in expected_messages:
+        actual_messages.append(handler.connector.messages.get())
+
+    assert len(actual_messages) == len(expected_messages)
+    for i in range(len(expected_messages)):  # pylint: disable=consider-using-enumerate
+        message = actual_messages[i]
+        assert message['key'] == 'message.send'
+        assert message['originator'] == expected_messages[i]['originator']
+        assert message['typing'] == (i < len(expected_messages)-1)
+
+
+def test_timing(handler):
+    q1 = get_message_queue(size=2)
+    q2 = get_message_queue(size=2)
+    handler.connector.raise_event(q1)
+    handler.connector.raise_event(q2)
+
+    messages = []
+    send_times = []
+    sleep_start_times = []
+    sleep_seconds = []
+    sleep_end_times = []
+    for _ in range(len(q1['messages']) + len(q2['messages'])):
+        messages.append(handler.connector.messages.get())
+        send_times.append(handler.connector.send_times.get())
+        sleep_start_times.append(handler.sleep_start_times.get())
+        sleep_seconds.append(handler.sleep_seconds.get())
+        sleep_end_times.append(handler.sleep_end_times.get())
+
+    # no sleep before first message
+    assert sleep_start_times[0] > send_times[0]
+    assert messages[0]['typing']
+
+    # at least 'seconds' sleep before sending next messages
+    assert (send_times[0] + sleep_seconds[0]) < sleep_end_times[0]
+    assert (send_times[0] + sleep_seconds[0]) < send_times[1]
+    assert messages[1]['typing']
+    assert (send_times[1] + sleep_seconds[1]) < sleep_end_times[1]
+    assert (send_times[1] + sleep_seconds[1]) < send_times[2]
+    assert messages[2]['typing']
+
+    # at least 'seconds' sleep after last message
+    assert (send_times[2] + sleep_seconds[2]) < sleep_end_times[3]
+    assert not messages[3]['typing']
+
+
+def test_drain(handler):
+    q1 = get_message_queue()
+    q2 = get_message_queue()
+    messages_count = len(q1['messages']) + len(q2['messages'])
+    handler.wpm = 0.01  # very slow, everything will just block
+    handler.connector.raise_event(q1)
+    handler.connector.raise_event(q2)
+
+    handler.connector.messages.get(timeout=0.1)  # no sleep before first message
+    with pytest.raises(Empty):
+        handler.connector.messages.get(timeout=0.1)
+
+    handler.connector.raise_event({'key': 'message.queue.drain'})
+
+    for _ in range(messages_count - 1):
+        handler.connector.messages.get()
+
+
+def test_queue_works_after_drain(handler):
+    handler.connector.raise_event({'key': 'message.queue.drain'})
+
+    q = get_message_queue()
+    expected_msg_count = len(q['messages'])
+    handler.connector.raise_event(q)
+
+    messages = []
+    for _ in range(expected_msg_count):
+        messages.append(handler.connector.messages.get())
+
+    assert len(messages) == expected_msg_count
+    assert handler._thread.is_alive()  # pylint: disable=protected-access
+
+
+def test_queue_can_be_stopped(handler):
+    handler.wpm = 0.01  # very slow, everything will just block
+
+    q = get_message_queue()
+    handler.connector.raise_event(q)
+    handler.cleanup()
+    handler.connector.raise_event({'key': 'message.queue.drain'})
+
+    assert not handler._thread.is_alive()  # pylint: disable=protected-access

tfw/components/frontend/message_sender.py

@@ -0,0 +1,30 @@
+class MessageSender:
+    def __init__(self, uplink):
+        self.uplink = uplink
+
+    def send(self, message, originator=None):
+        message = {
+            'key': 'message.send',
+            'message': message
+        }
+        if originator:
+            message['originator'] = originator
+        self.uplink.send_message(message)
+
+    def queue_messages(self, messages, originator=None):
+        message_queue = {
+            'key': 'message.queue',
+            'messages': []
+        }
+        for message in messages:
+            next_message = {'message': message}
+            if originator:
+                next_message['originator'] = originator
+            message_queue['messages'].append(next_message)
+        self.uplink.send_message(message_queue)
+
+    def set_originator(self, originator):
+        self.uplink.send_message({
+            'key': 'message.config',
+            'originator': originator
+        })

tfw/components/frontend/message_storage.py

@@ -0,0 +1,49 @@
+from abc import ABC, abstractmethod
+from contextlib import suppress
+
+
+class MessageStorage(ABC):
+    def __init__(self):
+        self._messages = []
+
+    def save_message(self, message):
+        with suppress(KeyError, AttributeError):
+            if self._filter_message(message):
+                self._messages.extend(self._transform_message(message))
+
+    @abstractmethod
+    def _filter_message(self, message):
+        raise NotImplementedError
+
+    def _transform_message(self, message):   # pylint: disable=no-self-use
+        yield message
+
+    def clear(self):
+        self._messages.clear()
+
+    @property
+    def messages(self):
+        yield from self._messages
+
+
+class FrontendMessageStorage(MessageStorage):
+    def _filter_message(self, message):
+        return message['key'].startswith((
+            'console.write',
+            'message.send',
+            'ide.read'
+        ))
+
+    def _transform_message(self, message):
+        transformations = {
+            'ide.read': self._delete_ide_content
+        }
+        if message['key'] in transformations:
+            yield from transformations[message['key']](message)
+        else:
+            yield message
+
+    @staticmethod
+    def _delete_ide_content(message):
+        del message['content']
+        yield message

tfw/components/fsm/__init__.py

@@ -0,0 +1 @@
+from .fsm_handler import FSMHandler

tfw/components/fsm/fsm_handler.py

@@ -0,0 +1,42 @@
+import logging
+
+from tfw.internals.crypto import KeyManager, sign_message
+from tfw.internals.networking import Scope, Intent
+
+from .fsm_updater import FSMUpdater
+
+LOG = logging.getLogger(__name__)
+
+
+class FSMHandler:
+    keys = ['fsm']
+    type_id = 'ControlEventHandler'
+
+    def __init__(self, *, fsm_type):
+        self.connector = None
+        self.fsm = fsm_type()
+        self._fsm_updater = FSMUpdater(self.fsm)
+        self.auth_key = KeyManager().auth_key
+
+        self.command_handlers = {
+            'fsm.trigger': self.handle_trigger,
+            'fsm.update' : self.handle_update
+        }
+
+    def handle_event(self, message, _):
+        try:
+            message = self.command_handlers[message['key']](message)
+            if message:
+                fsm_update_message = self._fsm_updater.fsm_update
+                sign_message(self.auth_key, fsm_update_message)
+                self.connector.send_message(fsm_update_message, Scope.BROADCAST, Intent.EVENT)
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def handle_trigger(self, message): # pylint: disable=inconsistent-return-statements
+        if self.fsm.step(message['transition']):
+            return message
+
+    def handle_update(self, message):
+        # pylint: disable=no-self-use
+        return message

tfw/components/fsm/fsm_updater.py

@@ -0,0 +1,26 @@
+class FSMUpdater:
+    def __init__(self, fsm):
+        self.fsm = fsm
+
+    @property
+    def fsm_update(self):
+        return {
+            'key': 'fsm.update',
+            **self.fsm_update_data
+        }
+
+    @property
+    def fsm_update_data(self):
+        valid_transitions = [
+            {'trigger': trigger}
+            for trigger in self.fsm.get_triggers(self.fsm.state)
+        ]
+        if not self.fsm.event_log:
+            return None
+        last_fsm_event = self.fsm.event_log[-1]
+        return {
+            'current_state': self.fsm.state,
+            'valid_transitions': valid_transitions,
+            'in_accepted_state': self.fsm.in_accepted_state,
+            'last_event': last_fsm_event
+        }

tfw/components/ide/__init__.py

@@ -0,0 +1,2 @@
+from .ide_handler import IdeHandler
+from .deploy_handler import DeployHandler

tfw/components/ide/deploy_handler.py

@@ -0,0 +1,34 @@
+import logging
+
+LOG = logging.getLogger(__name__)
+
+
+class DeployHandler:
+    keys = ['deploy.start', 'process.restart']
+
+    def __init__(self, process_name='webservice'):
+        self.connector = None
+        self.process_name = process_name
+
+        self.commands = {
+            'deploy.start': self.handle_deploy,
+            'process.restart': self.handle_process
+        }
+
+    def handle_event(self, message, _):
+        try:
+            self.commands[message['key']](message)
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def handle_deploy(self, _):
+        self.connector.send_message({
+            'key': 'process.restart',
+            'name': self.process_name
+        })
+
+    def handle_process(self, message):
+        response = {'key': 'deploy.finish'}
+        if 'error' in message:
+            response['error'] = message['error']
+        self.connector.send_message(response)

tfw/components/ide/file_manager/__init__.py

@@ -0,0 +1 @@
+from .file_manager import FileManager

tfw/components/ide/file_manager/file_manager.py

@@ -0,0 +1,66 @@
+import logging
+from functools import wraps
+from glob import glob
+from fnmatch import fnmatchcase
+from os.path import dirname, isdir, isfile, realpath, isabs
+
+LOG = logging.getLogger(__name__)
+
+
+def _with_is_allowed(func):
+    @wraps(func)
+    def wrapper(self, *args, **kwargs):
+        if self.is_allowed(args[0]):
+            return func(self, *args, **kwargs)
+        raise ValueError('Forbidden path.')
+    return wrapper
+
+
+class FileManager: # pylint: disable=too-many-instance-attributes
+    def __init__(self, patterns):
+        self.patterns = patterns
+
+    @property
+    def files(self):
+        return list(set(
+            path
+            for pattern in self.patterns
+            for path in glob(pattern, recursive=True)
+            if isfile(path) and self.is_allowed(path)
+        ))
+
+    @property
+    def parents(self):
+        return list(set(
+            self._find_directory(pattern)
+            for pattern in self.patterns
+        ))
+
+    @staticmethod
+    def _find_directory(pattern):
+        while pattern and not isdir(pattern):
+            pattern = dirname(pattern)
+        return pattern
+
+    def is_allowed(self, filepath):
+        return any(
+            fnmatchcase(realpath(filepath), pattern)
+            for pattern in self.patterns
+        )
+
+    def find_file(self, filename):
+        if not isabs(filename):
+            for filepath in self.files:
+                if filepath.endswith(filename):
+                    return filepath
+        return filename
+
+    @_with_is_allowed
+    def read_file(self, filepath): # pylint: disable=no-self-use
+        with open(filepath, 'rb', buffering=0) as ifile:
+            return ifile.read().decode(errors='surrogateescape')
+
+    @_with_is_allowed
+    def write_file(self, filepath, contents): # pylint: disable=no-self-use
+        with open(filepath, 'wb', buffering=0) as ofile:
+            ofile.write(contents.encode())

tfw/components/ide/file_manager/test_file_manager.py

@@ -0,0 +1,94 @@
+# pylint: disable=redefined-outer-name
+from dataclasses import dataclass
+from secrets import token_urlsafe
+from os import mkdir, symlink
+from os.path import join, realpath, basename
+from pathlib import Path
+from tempfile import TemporaryDirectory
+
+import pytest
+
+from .file_manager import FileManager
+
+
+@dataclass
+class ManagerContext:
+    workdir: str
+    subdir: str
+    subfile: str
+    manager: FileManager
+
+    def create_random_file(self, dirname, extension):
+        filename = self.join(f'{dirname}/{generate_name()}{extension}')
+        Path(filename).touch()
+        return filename
+
+    def create_random_folder(self, basepath):
+        dirname = self.join(f'{basepath}/{generate_name()}')
+        mkdir(dirname)
+        return dirname
+
+    def create_random_link(self, source, dirname, extension):
+        linkname = self.join(f'{dirname}/{generate_name()}{extension}')
+        symlink(source, linkname)
+        return linkname
+
+    def join(self, path):
+        return join(self.workdir, path)
+
+def generate_name():
+    return token_urlsafe(16)
+
+@pytest.fixture()
+def context():
+    with TemporaryDirectory() as workdir:
+        workdir = realpath(workdir)  # macOS uses a symlinked TMPDIR
+        subdir = join(workdir, generate_name())
+        subfile = join(subdir, generate_name() + '.txt')
+        mkdir(subdir)
+        Path(subfile).touch()
+        manager = FileManager([join(workdir, '**/*.txt')])
+        yield ManagerContext(workdir, subdir, subfile, manager)
+
+def test_matching_files(context):
+    newdir = context.create_random_folder(context.subdir)
+    newfile = context.create_random_file(newdir, '.txt')
+    newlink = context.create_random_link(newfile, newdir, '.txt')
+    assert set(context.manager.files) == {context.subfile, newfile, newlink}
+
+def test_unmatching_files(context):
+    newtxt = context.create_random_file(context.workdir, '.txt')
+    newbin = context.create_random_file(context.subdir, '.bin')
+    context.create_random_link(newtxt, context.subdir, '.txt')
+    context.create_random_link(newbin, context.subdir, '.txt')
+    assert context.manager.files == [context.subfile]
+
+def test_parents(context):
+    newdir = context.create_random_folder(context.workdir)
+    context.manager.patterns += [f'{newdir}/[!/@]*/**/?.c']
+    assert set(context.manager.parents) == {context.workdir, newdir}
+
+def test_read_write_file(context):
+    for _ in range(128):
+        content = token_urlsafe(32)
+        context.manager.write_file(context.subfile, content)
+        assert context.manager.read_file(context.subfile) == content
+        with open(context.subfile, 'r') as ifile:
+            assert ifile.read() == content
+
+def test_regular_ide_actions(context):
+    newfile1 = context.create_random_file(context.subdir, '.txt')
+    newfile2 = context.create_random_file(context.subdir, '.txt')
+    for _ in range(4):
+        context.manager.filename = newfile1
+        content1, content2 = token_urlsafe(32), token_urlsafe(32)
+        context.manager.write_file(newfile1, content1)
+        context.manager.write_file(newfile2, content2)
+        assert context.manager.read_file(newfile1) == content1
+        assert context.manager.read_file(newfile2) == content2
+
+def test_find_file(context):
+    for _ in range(5):
+        file_abs = context.create_random_file(context.subdir, '.txt')
+        file_base = basename(file_abs)
+        assert context.manager.find_file(file_base) == file_abs

tfw/components/ide/ide_handler.py

@@ -0,0 +1,106 @@
+import logging
+
+from tfw.internals.networking import Scope
+from tfw.internals.inotify import InotifyObserver
+
+from .file_manager import FileManager
+
+LOG = logging.getLogger(__name__)
+
+BUILD_ARTIFACTS = (
+    "*.a",
+    "*.class",
+    "*.dll",
+    "*.dylib",
+    "*.elf",
+    "*.exe",
+    "*.jar",
+    "*.ko",
+    "*.la",
+    "*.lib",
+    "*.lo",
+    "*.o",
+    "*.obj",
+    "*.out",
+    "*.py[cod]",
+    "*.so",
+    "*.so.*",
+    "*.tar.gz",
+    "*.zip",
+    "*__pycache__*"
+)
+
+
+class IdeHandler:
+    keys = ['ide']
+    type_id = 'ControlEventHandler'
+
+    def __init__(self, *, patterns, initial_file=None):
+        self.connector = None
+        self.filemanager = FileManager(patterns)
+        self._initial_file = initial_file or ''
+        self._ignore_inotify_src = ''
+
+        self.monitor = InotifyObserver(
+            path=self.filemanager.parents,
+            exclude=BUILD_ARTIFACTS
+        )
+        self.monitor.on_modified = self._reload_frontend
+        self.monitor.start()
+
+        self.commands = {
+            'ide.read'  : self.read,
+            'ide.write' : self.write
+        }
+
+    def _reload_frontend(self, event):  # pylint: disable=unused-argument
+        if self._ignore_inotify_src == event.src_path:
+            self._ignore_inotify_src = ''
+            return
+        self.send_message({'key': 'ide.reload'})
+
+    @property
+    def initial_file(self):
+        if not self.filemanager.is_allowed(self._initial_file):
+            self._initial_file = self.filemanager.files[0]
+        return self._initial_file
+
+    def send_message(self, message):
+        self.connector.send_message(message, scope=Scope.WEBSOCKET)
+
+    def handle_event(self, message, _):
+        try:
+            self.commands[message['key']](message)
+            message['files'] = self.filemanager.files
+            self.send_message(message)
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def read(self, message):
+        if 'patterns' in message:
+            self.filemanager.patterns = message['patterns']
+        try:
+            message['filename'] = self.filemanager.find_file(
+                message.get('filename') or self.initial_file
+            )
+            message['content'] = self.filemanager.read_file(message['filename'])
+        except (PermissionError, ValueError):
+            message['content'] = 'You have no permission to open that file :('
+        except FileNotFoundError:
+            message['content'] = 'This file does not exist :('
+        except Exception: # pylint: disable=broad-except
+            message['content'] = 'Failed to read file :('
+            LOG.exception('Error reading file!')
+
+    def write(self, message):
+        try:
+            self._ignore_inotify_src = message['filename']
+            self.filemanager.write_file(message['filename'], message['content'])
+        except KeyError:
+            LOG.error('You must provide a filename to write!')
+        except Exception: # pylint: disable=broad-except
+            LOG.exception('Error writing file!')
+        del message['content']
+
+    def cleanup(self):
+        self.monitor.stop()

tfw/components/pipe_io/__init__.py

@@ -0,0 +1,3 @@
+from .pipe_io_handler import PipeIOHandler, PipeIOHandlerBase
+from .command_handler import CommandHandler
+from .pipe_connector import ProxyPipeConnectorHandler

tfw/components/pipe_io/command_handler.py

@@ -0,0 +1,58 @@
+from subprocess import PIPE, Popen
+from functools import partial
+from os import getpgid, killpg
+from os.path import join
+from signal import SIGTERM
+from secrets import token_urlsafe
+from threading import Thread
+from contextlib import suppress
+
+from pipe_io_server import terminate_process_on_failure
+
+from .pipe_io_handler import PipeIOHandler, DEFAULT_PERMISSIONS
+
+
+class CommandHandler(PipeIOHandler):
+    def __init__(self, command, permissions=DEFAULT_PERMISSIONS):
+        super().__init__(
+            self._generate_tempfilename(),
+            self._generate_tempfilename(),
+            permissions
+        )
+
+        self._proc_stdin = open(self.pipe_io.out_pipe, 'rb')
+        self._proc_stdout = open(self.pipe_io.in_pipe, 'wb')
+        self._proc = Popen(
+            command, shell=True, executable='/bin/bash',
+            stdin=self._proc_stdin, stdout=self._proc_stdout, stderr=PIPE,
+            start_new_session=True
+        )
+        self._monitor_proc_thread = self._start_monitor_proc()
+
+    def _generate_tempfilename(self):
+        # pylint: disable=no-self-use
+        random_filename = partial(token_urlsafe, 10)
+        return join('/tmp', f'{type(self).__name__}.{random_filename()}')
+
+    def _start_monitor_proc(self):
+        thread = Thread(target=self._monitor_proc, daemon=True)
+        thread.start()
+        return thread
+
+    @terminate_process_on_failure
+    def _monitor_proc(self):
+        return_code = self._proc.wait()
+        if return_code == -int(SIGTERM):
+            # supervisord asked the program to terminate, this is fine
+            return
+        if return_code != 0:
+            _, stderr = self._proc.communicate()
+            raise RuntimeError(f'Subprocess failed ({return_code})! Stderr:\n{stderr.decode()}')
+
+    def cleanup(self):
+        with suppress(ProcessLookupError):
+            process_group_id = getpgid(self._proc.pid)
+            killpg(process_group_id, SIGTERM)
+            self._proc_stdin.close()
+            self._proc_stdout.close()
+        super().cleanup()

tfw/components/pipe_io/pipe_connector/__init__.py

@@ -0,0 +1 @@
+from .proxy_pipe_connector_handler import ProxyPipeConnectorHandler

tfw/components/pipe_io/pipe_connector/pipe_connector.py

@@ -0,0 +1,90 @@
+import logging
+from stat import S_ISFIFO
+from os import access, listdir, mkdir, stat, R_OK
+from os.path import exists, join
+
+from pipe_io_server import PipeWriterServer
+
+from tfw.internals.inotify import InotifyObserver, InotifyFileCreatedEvent, InotifyFileDeletedEvent
+
+LOG = logging.getLogger(__name__)
+
+
+class PipeConnector:
+    reader_pattern, writer_pattern = 'send', 'recv'
+
+    def __init__(self, path):
+        self.recv_pipes, self.send_pipes = {}, {}
+        self.observer = self._build_observer(path)
+        self.observer.on_any_event = self._on_any_event
+        self.observer.start()
+        self._connect_existing_pipes(path)
+
+    def _build_observer(self, path): # pylint: disable=no-self-use
+        if not exists(path):
+            mkdir(path)
+        if not access(path, R_OK):
+            raise ValueError('Path does not exist or is not accessible.')
+        return InotifyObserver(path, patterns=[f'*{self.reader_pattern}*', f'*{self.writer_pattern}*'])
+
+    def _connect_existing_pipes(self, path):
+        for node in listdir(path):
+            node_path = join(path, node)
+            if self._is_pipe(node_path):
+                self._create_pipe(node_path)
+                LOG.debug('Connected to existing pipe "%s"', node_path)
+
+    def _on_any_event(self, event):
+        path = event.src_path
+        if self._is_pipe(path) and isinstance(event, InotifyFileCreatedEvent):
+            self._create_pipe(path)
+            LOG.debug('Connected to new pipe "%s"', path)
+        elif isinstance(event, InotifyFileDeletedEvent):
+            self._delete_pipe(path)
+            LOG.debug('Disconnected from deleted pipe "%s"', path)
+
+    @staticmethod
+    def _is_pipe(path):
+        return exists(path) and S_ISFIFO(stat(path).st_mode)
+
+    def _create_pipe(self, path):
+        if self._find_pipe(path):
+            return
+        server = None
+        if self.writer_pattern in path:
+            pipes, server = self.recv_pipes, self.build_writer(path)
+        elif self.reader_pattern in path:
+            pipes, server = self.send_pipes, self.build_reader(path)
+        if server:
+            server.start()
+            pipes[path] = server
+
+    def _find_pipe(self, path):
+        pipes = None
+        if path in self.recv_pipes.keys():
+            pipes = self.recv_pipes
+        if path in self.send_pipes.keys():
+            pipes = self.send_pipes
+        return pipes
+
+    def build_reader(self, path): # pylint: disable=no-self-use
+        raise NotImplementedError()
+
+    def build_writer(self, path): # pylint: disable=no-self-use
+        return PipeWriterServer(path, manage_pipes=False)
+
+    def _delete_pipe(self, path):
+        pipes = self._find_pipe(path)
+        if pipes:
+            pipes[path].stop()
+            del pipes[path]
+
+    def broadcast(self, message):
+        for server in self.recv_pipes.values():
+            server.send_message(message)
+
+    def stop(self):
+        for pipe in self.recv_pipes.values():
+            pipe.stop()
+        for pipe in self.send_pipes.values():
+            pipe.stop()

tfw/components/pipe_io/pipe_connector/proxy_pipe_connector_handler.py

@@ -0,0 +1,46 @@
+import logging
+from threading import Lock
+from json import dumps, loads, JSONDecodeError
+
+from pipe_io_server import PipeReaderServer
+
+from .pipe_connector import PipeConnector
+
+LOG = logging.getLogger(__name__)
+
+
+class ProxyPipeConnectorHandler:
+    keys = ['']
+
+    def __init__(self, path):
+        self.connector, self.pipes = None, None
+        self.path = path
+
+    def start(self):
+        self.pipes = ProxyPipeConnector(self.path, self.connector)
+
+    def handle_event(self, message, _):
+        self.pipes.broadcast(dumps(message).encode())
+
+    def cleanup(self):
+        self.pipes.stop()
+
+
+class ProxyPipeConnector(PipeConnector):
+    def __init__(self, path, connector):
+        self.connector = connector
+        self.mutex = Lock()
+        super().__init__(path)
+
+    def build_reader(self, path):
+        reader = PipeReaderServer(path, manage_pipes=False)
+        reader.handle_message = self._handle_message
+        return reader
+
+    def _handle_message(self, message):
+        try:
+            json_object = loads(message)
+            with self.mutex:
+                self.connector.send_message(json_object)
+        except JSONDecodeError:
+            LOG.error('Received invalid JSON message: %s', message)

tfw/components/pipe_io/pipe_connector/test_proxy_pipe_connector.py

@@ -0,0 +1,157 @@
+# pylint: disable=redefined-outer-name
+from enum import Enum
+from dataclasses import dataclass
+from json import dumps
+from secrets import token_urlsafe
+from os import urandom, mkfifo, mkdir, remove
+from os.path import join
+from pathlib import Path
+from tempfile import TemporaryDirectory
+
+import pytest
+from tfw.internals.inotify import InotifyFileCreatedEvent, InotifyFileDeletedEvent
+
+from .proxy_pipe_connector_handler import ProxyPipeConnector
+
+
+class Action(Enum):
+    SEND = 'send'
+    RECV = 'recv'
+
+
+@dataclass
+class PipeContext:
+    workdir: str
+    pipes: ProxyPipeConnector
+
+    def emit_pipe_creation_event(self, action, inode_creator):
+        filename = self.join(f'{self.generate_name()}_{action.value}')
+        inode_creator(filename)
+        self.pipes.observer.on_any_event(InotifyFileCreatedEvent(filename))
+        return filename
+
+    def join(self, path):
+        return join(self.workdir, path)
+
+    @staticmethod
+    def generate_name():
+        return urandom(4).hex()
+
+
+class MockPipeConnector(ProxyPipeConnector):
+    def __init__(self, path, connector):
+        self.reader_events, self.writer_events = [], []
+        super().__init__(path, connector)
+
+    def _build_observer(self, path):
+        return MockObserver()
+
+    def build_reader(self, path):
+        self.reader_events.append(path)
+        reader = MockPipeServer()
+        reader.handle_message = self._handle_message
+        return reader
+
+    def build_writer(self, path):
+        self.writer_events.append(path)
+        return MockPipeServer()
+
+
+class MockObserver:
+    def start(self):
+        pass
+
+    def on_any_event(self, event):
+        pass
+
+
+class MockPipeServer:
+    def __init__(self):
+        self.messages = []
+
+    def handle_message(self, message):
+        pass
+
+    def send_message(self, message):
+        self.messages.append(message)
+
+    def start(self):
+        pass
+
+    def stop(self):
+        pass
+
+
+class MockConnector: # pylint: disable=too-few-public-methods
+    def __init__(self):
+        self.messages = []
+
+    def send_message(self, message):
+        self.messages.append(message)
+
+
+@pytest.fixture
+def workdir():
+    with TemporaryDirectory() as workdir:
+        yield workdir
+
+
+@pytest.fixture
+def context(workdir):
+    mkfifo(join(workdir, Action.SEND.value))
+    mkfifo(join(workdir, Action.RECV.value))
+    yield PipeContext(workdir, MockPipeConnector(workdir, MockConnector()))
+
+
+def test_existing_pipe_connection(context):
+    assert join(context.workdir, Action.SEND.value) in context.pipes.send_pipes.keys()
+    assert join(context.workdir, Action.RECV.value) in context.pipes.recv_pipes.keys()
+
+
+def test_pipe_creation_deletion(context):
+    cases = [
+        (Action.RECV, context.pipes.recv_pipes, context.pipes.writer_events),
+        (Action.SEND, context.pipes.send_pipes, context.pipes.reader_events)
+    ]
+
+    for action, pipes, events in cases:
+        path = context.emit_pipe_creation_event(action, mkfifo)
+        assert events[-1] == path
+        assert path in pipes.keys()
+        remove(path)
+        context.pipes.observer.on_any_event(InotifyFileDeletedEvent(path))
+        assert path not in pipes.keys()
+
+
+def test_handle_message(context):
+    path = context.emit_pipe_creation_event(Action.SEND, mkfifo)
+    payload = {'key': token_urlsafe(16)}
+    context.pipes.send_pipes[path].handle_message(dumps(payload))
+    assert context.pipes.connector.messages[-1] == payload
+    context.pipes.send_pipes[path].handle_message(token_urlsafe(32))
+    assert len(context.pipes.connector.messages) == 1
+
+
+def test_broadcast(context):
+    paths = [
+        context.emit_pipe_creation_event(Action.RECV, mkfifo)
+        for _ in range(32)
+    ]
+    payload = {'key': token_urlsafe(16)}
+
+    context.pipes.broadcast(payload)
+    for path in paths:
+        assert context.pipes.recv_pipes[path].messages[-1] == payload
+
+def test_inode_types(context):
+    touch = lambda path: Path(path).touch()
+    cases = [
+        (Action.RECV, context.pipes.recv_pipes, mkdir),
+        (Action.SEND, context.pipes.send_pipes, mkdir),
+        (Action.RECV, context.pipes.recv_pipes, touch),
+        (Action.SEND, context.pipes.send_pipes, touch)
+    ]
+
+    for action, pipes, creator in cases:
+        path = context.emit_pipe_creation_event(action, creator)
+        assert path not in pipes.keys()

tfw/components/pipe_io/pipe_io_handler.py

@@ -0,0 +1,47 @@
+import logging
+from abc import abstractmethod
+from json import loads, dumps
+
+from pipe_io_server import PipeIOServer
+
+LOG = logging.getLogger(__name__)
+DEFAULT_PERMISSIONS = 0o600
+
+
+class PipeIOHandlerBase:
+    keys = ['']
+
+    def __init__(self, in_pipe_path, out_pipe_path, permissions=DEFAULT_PERMISSIONS):
+        self.connector = None
+        self.in_pipe = in_pipe_path
+        self.out_pipe = out_pipe_path
+        self.pipe_io = PipeIOServer(
+            in_pipe_path,
+            out_pipe_path,
+            permissions
+        )
+        self.pipe_io.handle_message = self._server_handle_message
+        self.pipe_io.start()
+
+    def _server_handle_message(self, message):
+        try:
+            self.handle_pipe_event(message)
+        except:  # pylint: disable=bare-except
+            LOG.exception('Failed to handle message %s from pipe %s!', message, self.in_pipe)
+
+    @abstractmethod
+    def handle_pipe_event(self, message_bytes):
+        raise NotImplementedError()
+
+    def cleanup(self):
+        self.pipe_io.stop()
+
+
+class PipeIOHandler(PipeIOHandlerBase):
+    def handle_event(self, message, _):
+        json_bytes = dumps(message).encode()
+        self.pipe_io.send_message(json_bytes)
+
+    def handle_pipe_event(self, message_bytes):
+        json = loads(message_bytes)
+        self.connector.send_message(json)

tfw/components/pipe_io/test_pipe_io_handler.py

@@ -0,0 +1,45 @@
+# pylint: disable=redefined-outer-name
+from tempfile import TemporaryDirectory
+from os.path import join
+from queue import Queue
+from json import dumps, loads
+
+import pytest
+
+from .pipe_io_handler import PipeIOHandler
+
+
+@pytest.fixture
+def pipe_io():
+    with TemporaryDirectory() as tmpdir:
+        pipeio = PipeIOHandler(
+            join(tmpdir, 'in'),
+            join(tmpdir, 'out'),
+            permissions=0o600
+        )
+        pipeio.connector = MockConnector()
+        yield pipeio
+        pipeio.cleanup()
+
+
+class MockConnector:
+    def __init__(self):
+        self.messages = Queue()
+
+    def send_message(self, msg):
+        self.messages.put(msg)
+
+
+def test_pipe_io_handler_recv(pipe_io):
+    test_msg = {'key': 'cica'}
+    with open(pipe_io.in_pipe, 'w') as ofile:
+        ofile.write(dumps(test_msg) + '\n')
+
+    assert pipe_io.connector.messages.get() == test_msg
+
+
+def test_pipe_io_handler_send(pipe_io):
+    test_msg = {'key': 'cica'}
+    pipe_io.handle_event(test_msg, None)
+    with open(pipe_io.out_pipe, 'r') as ifile:
+        assert loads(ifile.readline()) == test_msg

tfw/components/process_management/__init__.py

@@ -0,0 +1,2 @@
+from .process_handler import ProcessHandler
+from .process_log_handler import ProcessLogHandler

tfw/components/process_management/log_inotify_observer.py

@@ -0,0 +1,34 @@
+from tfw.internals.networking import Scope, Intent
+from tfw.internals.inotify import InotifyObserver
+
+from .supervisor import ProcessLogManager
+
+
+class LogInotifyObserver(InotifyObserver, ProcessLogManager):
+    def __init__(self, connector, process_name, supervisor_uri, log_tail=0):
+        self._connector = connector
+        self._process_name = process_name
+        self.log_tail = log_tail
+        self._procinfo = None
+        ProcessLogManager.__init__(self, supervisor_uri)
+        InotifyObserver.__init__(self, self._get_logfiles())
+
+    def _get_logfiles(self):
+        self._procinfo = self.supervisor.getProcessInfo(self._process_name)
+        return self._procinfo['stdout_logfile'], self._procinfo['stderr_logfile']
+
+    @property
+    def process_name(self):
+        return self._process_name
+
+    @process_name.setter
+    def process_name(self, process_name):
+        self._process_name = process_name
+        self.paths = self._get_logfiles()
+
+    def on_modified(self, event):
+        self._connector.send_message({
+            'key': 'process.log.new',
+            'stdout': self.read_stdout(self.process_name, tail=self.log_tail),
+            'stderr': self.read_stderr(self.process_name, tail=self.log_tail)
+        }, Scope.BROADCAST, Intent.EVENT)

tfw/components/process_management/process_handler.py

@@ -0,0 +1,33 @@
+import logging
+from xmlrpc.client import Fault as SupervisorFault
+
+from tfw.internals.networking import Scope, Intent
+
+from .supervisor import ProcessManager
+
+LOG = logging.getLogger(__name__)
+
+
+class ProcessHandler(ProcessManager):
+    keys = ['process']
+    type_id = 'ControlEventHandler'
+
+    def __init__(self, *, supervisor_uri):
+        ProcessManager.__init__(self, supervisor_uri)
+
+        self.commands = {
+            'process.start': self.start_process,
+            'process.stop': self.stop_process,
+            'process.restart': self.restart_process
+        }
+
+    def handle_event(self, message, connector):
+        try:
+            try:
+                self.commands[message['key']](message['name'])
+            except SupervisorFault as fault:
+                message['error'] = fault.faultString
+            connector.send_message(message, scope=Scope.BROADCAST, intent=Intent.EVENT)
+        except KeyError:
+            if not message['key'].startswith('process.log'):
+                LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)

tfw/components/process_management/process_log_handler.py

@@ -0,0 +1,44 @@
+import logging
+
+from .log_inotify_observer import LogInotifyObserver
+
+LOG = logging.getLogger(__name__)
+
+
+class ProcessLogHandler:
+    keys = ['process.log']
+    type_id = 'ControlEventHandler'
+
+    def __init__(self, *, process_name, supervisor_uri, log_tail=0):
+        self.connector, self._monitor = None, None
+        self.process_name = process_name
+        self._supervisor_uri = supervisor_uri
+        self._initial_log_tail = log_tail
+
+        self.command_handlers = {
+            'process.log.set': self.handle_set
+        }
+
+    def start(self):
+        self._monitor = LogInotifyObserver(
+            connector=self.connector,
+            process_name=self.process_name,
+            supervisor_uri=self._supervisor_uri,
+            log_tail=self._initial_log_tail
+        )
+        self._monitor.start()
+
+    def handle_event(self, message, _):
+        try:
+            self.command_handlers[message['key']](message)
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def handle_set(self, data):
+        if data.get('name'):
+            self._monitor.process_name = data['name']
+        if data.get('tail'):
+            self._monitor.log_tail = data['tail']
+
+    def cleanup(self):
+        self._monitor.stop()

tfw/components/process_management/supervisor.py

@@ -1,22 +1,15 @@
-# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-# All Rights Reserved. See LICENSE file for details.
-
+from os import remove
+from contextlib import suppress
 import xmlrpc.client
 from xmlrpc.client import Fault as SupervisorFault
-from contextlib import suppress
-from os import remove
-
-from tfw.decorators import lazy_property
-from tfw.config import TFWENV
 
 
-class SupervisorBaseMixin:
-    @lazy_property
-    def supervisor(self):
-        return xmlrpc.client.ServerProxy(TFWENV.SUPERVISOR_HTTP_URI).supervisor
+class SupervisorBase:
+    def __init__(self, supervisor_uri):
+        self.supervisor = xmlrpc.client.ServerProxy(supervisor_uri).supervisor
 
 
-class SupervisorMixin(SupervisorBaseMixin):
+class ProcessManager(SupervisorBase):
     def stop_process(self, process_name):
         with suppress(SupervisorFault):
             self.supervisor.stopProcess(process_name)
@@ -29,7 +22,7 @@ class SupervisorMixin(SupervisorBaseMixin):
         self.start_process(process_name)
 
 
-class SupervisorLogMixin(SupervisorBaseMixin):
+class ProcessLogManager(SupervisorBase):
     def read_stdout(self, process_name, tail=0):
         return self.supervisor.readProcessStdoutLog(process_name, -tail, 0)
 

tfw/components/snapshots/__init__.py

@@ -0,0 +1 @@
+from .snapshot_handler import SnapshotHandler

tfw/components/snapshots/snapshot_handler.py

@@ -0,0 +1,78 @@
+import logging
+from os.path import join as joinpath
+from os.path import basename
+from os import makedirs
+from datetime import datetime
+
+from dateutil import parser as dateparser
+
+from .snapshot_provider import SnapshotProvider
+
+LOG = logging.getLogger(__name__)
+
+
+class SnapshotHandler:
+    keys = ['snapshot']
+
+    def __init__(self, *, directories, snapshots_dir, exclude_unix_patterns=None):
+        self._snapshots_dir = snapshots_dir
+        self.snapshot_providers = {}
+        self._exclude_unix_patterns = exclude_unix_patterns
+        self.init_snapshot_providers(directories)
+
+        self.command_handlers = {
+            'snapshot.take': self.handle_take_snapshot,
+            'snapshot.restore': self.handle_restore_snapshot,
+            'snapshot.exclude': self.handle_exclude
+        }
+
+    def init_snapshot_providers(self, directories):
+        for index, directory in enumerate(directories):
+            git_dir = self.init_git_dir(index, directory)
+            self.snapshot_providers[directory] = SnapshotProvider(
+                directory,
+                git_dir,
+                self._exclude_unix_patterns
+            )
+
+    def init_git_dir(self, index, directory):
+        git_dir = joinpath(
+            self._snapshots_dir,
+            f'{basename(directory)}-{index}'
+        )
+        makedirs(git_dir, exist_ok=True)
+        return git_dir
+
+    def handle_event(self, message, _):
+        try:
+            self.command_handlers[message['key']](message)
+        except KeyError:
+            LOG.error('IGNORING MESSAGE: Invalid message received: %s', message)
+
+    def handle_take_snapshot(self, _):
+        LOG.debug('Taking snapshots of directories %s', self.snapshot_providers.keys())
+        for provider in self.snapshot_providers.values():
+            provider.take_snapshot()
+
+    def handle_restore_snapshot(self, message):
+        date = dateparser.parse(
+            message.get(
+                'value',
+                datetime.now().isoformat()
+            )
+        )
+        LOG.debug(
+            'Restoring snapshots (@ %s) of directories %s',
+            date,
+            self.snapshot_providers.keys()
+        )
+        for provider in self.snapshot_providers.values():
+            provider.restore_snapshot(date)
+
+    def handle_exclude(self, message):
+        exclude_unix_patterns = message['value']
+        if not isinstance(exclude_unix_patterns, list):
+            raise KeyError
+
+        for provider in self.snapshot_providers.values():
+            provider.exclude = exclude_unix_patterns

tfw/components/snapshots/snapshot_provider.py

@@ -0,0 +1,221 @@
+import re
+from subprocess import run, CalledProcessError, PIPE
+from getpass import getuser
+from os.path import isdir
+from os.path import join as joinpath
+from uuid import uuid4
+
+from dateutil import parser as dateparser
+
+
+class SnapshotProvider:
+    def __init__(self, directory, git_dir, exclude_unix_patterns=None):
+        self._classname = self.__class__.__name__
+        author = f'{getuser()} via TFW {self._classname}'
+        self.gitenv = {
+            'GIT_DIR': git_dir,
+            'GIT_WORK_TREE': directory,
+            'GIT_AUTHOR_NAME': author,
+            'GIT_AUTHOR_EMAIL': '',
+            'GIT_COMMITTER_NAME': author,
+            'GIT_COMMITTER_EMAIL': '',
+            'GIT_PAGER': 'cat'
+        }
+
+        self._init_repo()
+        self.__last_valid_branch = self._branch
+        if exclude_unix_patterns:
+            self.exclude = exclude_unix_patterns
+
+    def _init_repo(self):
+        self._check_environment()
+
+        if not self._repo_is_initialized:
+            self._run(('git', 'init'))
+
+        if self._number_of_commits == 0:
+            try:
+                self._snapshot()
+            except CalledProcessError:
+                raise EnvironmentError(f'{self._classname} cannot init on empty directories!')
+
+        self._check_head_not_detached()
+
+    def _check_environment(self):
+        if not isdir(self.gitenv['GIT_DIR']) or not isdir(self.gitenv['GIT_WORK_TREE']):
+            raise EnvironmentError(f'{self._classname}: "directory" and "git_dir" must exist!')
+
+    @property
+    def _repo_is_initialized(self):
+        return self._run(
+            ('git', 'status'),
+            check=False
+        ).returncode == 0
+
+    @property
+    def _number_of_commits(self):
+        return int(
+            self._get_stdout((
+                'git', 'rev-list',
+                '--all',
+                '--count'
+            ))
+        )
+
+    def _snapshot(self):
+        self._run((
+            'git', 'add',
+            '-A'
+        ))
+        try:
+            self._get_stdout((
+                'git', 'commit',
+                '-m', 'Snapshot'
+            ))
+        except CalledProcessError as err:
+            if b'nothing to commit, working tree clean' not in err.output:
+                raise
+
+    def _check_head_not_detached(self):
+        if self._head_detached:
+            raise EnvironmentError(f'{self._classname} cannot init from detached HEAD state!')
+
+    @property
+    def _head_detached(self):
+        return self._branch == 'HEAD'
+
+    @property
+    def _branch(self):
+        return self._get_stdout((
+            'git', 'rev-parse',
+            '--abbrev-ref', 'HEAD'
+        ))
+
+    def _get_stdout(self, *args, **kwargs):
+        kwargs['stdout'] = PIPE
+        kwargs['stderr'] = PIPE
+        stdout_bytes = self._run(*args, **kwargs).stdout
+        return stdout_bytes.decode().rstrip('\n')
+
+    def _run(self, *args, **kwargs):
+        if 'check' not in kwargs:
+            kwargs['check'] = True
+        if 'env' not in kwargs:
+            kwargs['env'] = self.gitenv
+        return run(*args, **kwargs)
+
+    @property
+    def exclude(self):
+        with open(self._exclude_path, 'r') as ofile:
+            return ofile.read()
+
+    @exclude.setter
+    def exclude(self, exclude_patterns):
+        with open(self._exclude_path, 'w') as ifile:
+            ifile.write('\n'.join(exclude_patterns))
+
+    @property
+    def _exclude_path(self):
+        return joinpath(
+            self.gitenv['GIT_DIR'],
+            'info',
+            'exclude'
+        )
+
+    def take_snapshot(self):
+        if self._head_detached:
+            self._checkout_new_branch_from_head()
+        self._snapshot()
+
+    def _checkout_new_branch_from_head(self):
+        branch_name = str(uuid4())
+        self._run((
+            'git', 'branch',
+            branch_name
+        ))
+        self._checkout(branch_name)
+
+    def _checkout(self, what):
+        self._run((
+            'git', 'checkout',
+            what
+        ))
+
+    def restore_snapshot(self, date):
+        commit = self._get_commit_from_timestamp(date)
+        branch = self._last_valid_branch
+        if commit == self._latest_commit_on_branch(branch):
+            commit = branch
+        self._checkout(commit)
+
+    def _get_commit_from_timestamp(self, date):
+        commit = self._get_stdout((
+            'git', 'rev-list',
+            '--date=iso',
+            '-n', '1',
+            f'--before="{date.isoformat()}"',
+            self._last_valid_branch
+        ))
+        if not commit:
+            commit = self._get_oldest_parent_of_head()
+        return commit
+
+    def _get_oldest_parent_of_head(self):
+        return self._get_stdout((
+            'git',
+            'rev-list',
+            '--max-parents=0',
+            'HEAD'
+        ))
+
+    @property
+    def _last_valid_branch(self):
+        if not self._head_detached:
+            self.__last_valid_branch = self._branch
+        return self.__last_valid_branch
+
+    def _latest_commit_on_branch(self, branch):
+        return self._get_stdout((
+            'git', 'log',
+            '-n', '1',
+            '--pretty=format:%H',
+            branch
+        ))
+
+    @property
+    def all_timelines(self):
+        return self._branches
+
+    @property
+    def _branches(self):
+        git_branch_output = self._get_stdout(('git', 'branch'))
+        regex_pattern = re.compile(r'(?:[^\S\n]|[*])')  # matches '*' and non-newline whitespace chars
+        return re.sub(regex_pattern, '', git_branch_output).splitlines()
+
+    @property
+    def timeline(self):
+        return self._last_valid_branch
+
+    @timeline.setter
+    def timeline(self, value):
+        self._checkout(value)
+
+    @property
+    def snapshots(self):
+        return self._pretty_log_branch()
+
+    def _pretty_log_branch(self):
+        git_log_output = self._get_stdout((
+            'git', 'log',
+            '--pretty=%H@%aI'
+        ))
+
+        commits = []
+        for line in git_log_output.splitlines():
+            commit_hash, timestamp = line.split('@')
+            commits.append({
+                'hash': commit_hash,
+                'timestamp': dateparser.parse(timestamp)
+            })
+
+        return commits

tfw/components/terminal/__init__.py

@@ -0,0 +1,3 @@
+from .terminal_handler import TerminalHandler
+from .terminal_commands_handler import TerminalCommandsHandler
+from .commands_equal import CommandsEqual

tfw/components/terminal/commands_equal.py

@@ -0,0 +1,107 @@
+from shlex import split
+from re import search
+
+from tfw.internals.lazy import lazy_property
+
+
+class CommandsEqual:
+    # pylint: disable=too-many-arguments
+    """
+    This class is useful for comparing executed commands with
+    excepted commands (i.e. when triggering a state change when
+    the correct command is executed).
+
+    Note that in most cases you should test the changes
+    caused by the commands instead of just checking command history
+    (stuff can be done in countless ways and preparing for every
+    single case is impossible). This should only be used when
+    testing the changes would be very difficult, like when
+    explaining stuff with cli tools and such.
+
+    This class implicitly converts to bool, use it like
+    if CommandsEqual(...): ...
+
+    It tries detecting differing command parameter orders with similar
+    semantics and provides fuzzy logic options.
+    The rationale behind this is that a few false positives
+    are better than only accepting a single version of a command
+    (i.e. using ==).
+    """
+    def __init__(
+            self, command_1, command_2,
+            fuzzyness=1, begin_similarly=True,
+            include_patterns=None, exclude_patterns=None
+    ):
+        """
+        :param command_1: Compared command 1
+        :param command_2: Compared command 2
+        :param fuzzyness: float between 0 and 1.
+                          the percentage of arguments required to
+                          match between commands to result in True.
+                          i.e 1 means 100% - all arguments need to be
+                          present in both commands, while 0.75
+                          would mean 75% - in case of 4 arguments
+                          1 could differ between the commands.
+        :param begin_similarly: bool, the first word of the commands
+                                must match
+        :param include_patterns: list of regex patterns the commands
+                                 must include
+        :param exclude_patterns: list of regex patterns the commands
+                                 must exclude
+        """
+        self.command_1 = split(command_1)
+        self.command_2 = split(command_2)
+        self.fuzzyness = fuzzyness
+        self.begin_similarly = begin_similarly
+        self.include_patterns = include_patterns
+        self.exclude_patterns = exclude_patterns
+
+    def __bool__(self):
+        if self.begin_similarly:
+            if not self.beginnings_are_equal:
+                return False
+
+        if self.include_patterns is not None:
+            if not self.commands_contain_include_patterns:
+                return False
+
+        if self.exclude_patterns is not None:
+            if not self.commands_contain_no_exclude_patterns:
+                return False
+
+        return self.similarity >= self.fuzzyness
+
+    @lazy_property
+    def beginnings_are_equal(self):
+        return self.command_1[0] == self.command_2[0]
+
+    @lazy_property
+    def commands_contain_include_patterns(self):
+        return all((
+            self.contains_regex_patterns(self.command_1, self.include_patterns),
+            self.contains_regex_patterns(self.command_2, self.include_patterns)
+        ))
+
+    @lazy_property
+    def commands_contain_no_exclude_patterns(self):
+        return all((
+            not self.contains_regex_patterns(self.command_1, self.exclude_patterns),
+            not self.contains_regex_patterns(self.command_2, self.exclude_patterns)
+        ))
+
+    @staticmethod
+    def contains_regex_patterns(command, regex_parts):
+        command = ' '.join(command)
+        for pattern in regex_parts:
+            if not search(pattern, command):
+                return False
+        return True
+
+    @lazy_property
+    def similarity(self):
+        parts_1 = set(self.command_1)
+        parts_2 = set(self.command_2)
+
+        difference = parts_1 - parts_2
+        deviance = len(difference) / len(max(parts_1, parts_2))
+        return 1 - deviance