Rework EventHandler situation

lib/tfw/components/__init__.py

@@ -6,3 +6,4 @@ from .file_manager import FileManager
 from .history_monitor import HistoryMonitor, BashMonitor, GDBMonitor
 from .snapshot_provider import SnapshotProvider
 from .terminal_commands import TerminalCommands
+from .fsm_aware import FSMAware

lib/tfw/components/fsm_aware.py

@@ -0,0 +1,45 @@
+# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
+# All Rights Reserved. See LICENSE file for details.
+
+import logging
+
+from tfw.crypto import KeyManager, verify_message
+
+LOG = logging.getLogger(__name__)
+
+
+class FSMAware:
+    """
+    Base class for stuff that has to be aware of the framework FSM.
+    This is done by processing 'fsm_update' messages.
+    """
+    def __init__(self):
+        self.fsm_state = None
+        self.fsm_in_accepted_state = False
+        self.fsm_event_log = []
+        self._auth_key = KeyManager().auth_key
+
+    def update_fsm_data(self, message):
+        if message['key'] == 'fsm_update' and verify_message(self._auth_key, message):
+            self._handle_fsm_update(message)
+            return True
+        return False
+
+    def _handle_fsm_update(self, message):
+        try:
+            update_data = message['data']
+            new_state = update_data['current_state']
+            if self.fsm_state != new_state:
+                self.handle_fsm_step(**update_data)
+            self.fsm_state = new_state
+            self.fsm_in_accepted_state = update_data['in_accepted_state']
+            self.fsm_event_log.append(update_data)
+        except KeyError:
+            LOG.error('Invalid fsm_update message received!')
+
+    def handle_fsm_step(self, **kwargs):
+        """
+        Called in case the TFW FSM has stepped.
+
+        :param kwargs: fsm_update 'data' field
+        """