Implement first version of DirectorySnapshottingEventHandler

Dockerfile

@@ -38,6 +38,7 @@ ENV PYTHONPATH="/usr/local/lib"                                            \
     TFW_FRONTEND_DIR="/srv/frontend"                                       \
     TFW_DIR="/.tfw"                                                        \
     TFW_SERVER_DIR="/.tfw/tfw_server"                                      \
+    TFW_SNAPSHOTS_DIR="/.tfw/snapshots"                                    \
     TFW_AUTH_KEY="/tmp/tfw-auth.key"                                       \
     TFW_HISTFILE="/home/${AVATAO_USER}/.bash_history"                      \
     PROMPT_COMMAND="history -a"

lib/tfw/components/__init__.py

@@ -10,3 +10,4 @@ from .terminal_commands import TerminalCommands
 from .log_monitoring_event_handler import LogMonitoringEventHandler
 from .fsm_managing_event_handler import FSMManagingEventHandler
 from .snapshot_provider import SnapshotProvider
+from .directory_snapshotting_event_handler import DirectorySnapshottingEventHandler

lib/tfw/components/directory_snapshotting_event_handler.py

@@ -0,0 +1,56 @@
+# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
+# All Rights Reserved. See LICENSE file for details.
+
+from os.path import join as joinpath
+from os.path import basename
+from os import makedirs
+from uuid import uuid4
+
+from dateutil import parser as dateparser
+
+from tfw.event_handler_base import EventHandlerBase
+from tfw.components.snapshot_provider import SnapshotProvider
+from tfw.config import TFWENV
+from tfw.config.logs import logging
+
+LOG = logging.getLogger(__name__)
+
+
+class DirectorySnapshottingEventHandler(EventHandlerBase):
+    def __init__(self, key, directories):
+        super().__init__(key)
+        self.snapshot_providers = {}
+        self.init_snapshot_providers(directories)
+
+        self.command_handlers = {
+            'take_snapshot': self.handle_take_snapshot,
+            'restore_snapshot': self.handle_restore_snapshot
+        }
+
+    def init_snapshot_providers(self, directories):
+        for directory in directories:
+            git_dir = joinpath(
+                TFWENV.SNAPSHOTS_DIR,
+                f'{basename(directory)}-{str(uuid4())}'
+            )
+            makedirs(git_dir, exist_ok=True)
+            self.snapshot_providers[directory] = SnapshotProvider(directory, git_dir)
+
+    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_take_snapshot(self, data):
+        for provider in self.snapshot_providers.values():
+            provider.take_snapshot()
+        return data
+
+    def handle_restore_snapshot(self, data):
+        date = dateparser.parse(data['value'])
+        for provider in self.snapshot_providers.values():
+            provider.restore_snapshot(date)
+        return data

requirements.txt

@@ -6,3 +6,4 @@ watchdog==0.8.3
 PyYAML==3.12
 Jinja2==2.10
 cryptography==2.2.2
+python-dateutil==2.7.3