Add FSMAwareEH example to event_handler_main

solvable/src/event_handler_main.py

@@ -3,7 +3,7 @@ from functools import partial
 
 from tornado.ioloop import IOLoop
 
-from tfw import YamlFSM
+from tfw import YamlFSM, FSMAwareEventHandler
 from tfw.components import IdeEventHandler, TerminalEventHandler
 from tfw.components import ProcessManagingEventHandler, BashMonitor
 from tfw.components import TerminalCommands, LogMonitoringEventHandler
@@ -13,8 +13,6 @@ from tfw.config import TFWENV
 from tfw.config.logs import logging
 from tao.config import TAOENV
 
-from test_fsm import TestFSM
-
 LOG = logging.getLogger(__name__)
 
 
@@ -80,7 +78,27 @@ class TestCommands(TerminalCommands):
         })
 
 
+class MessageFSMStepsEventHandler(FSMAwareEventHandler):
+    """
+    This example EventHandler is capable of detecting FSM state.
+    !! Please remove from production code !!
+    """
+    def handle_event(self, message):
+        pass
+
+    def handle_fsm_step(self, from_state, to_state, trigger):
+        """
+        When the FSM steps this method is invoked.
+        """
+        MessageSender().send(
+            'FSM info',
+            f'FSM has stepped from state "{from_state}" '
+            f'to state "{to_state}" in response to trigger "{trigger}"'
+        )
+
+
 if __name__ == '__main__':
+    # TFW component EventHandlers (builtins, required for their respective functionalities)
     fsm = FSMManagingEventHandler( # TFW FSM
         key='fsm',
         fsm_type=partial(YamlFSM, 'test_fsm.yml')
@@ -105,14 +123,22 @@ if __name__ == '__main__':
         process_name='webservice',
         log_tail=2000
     )
-    eventhandlers = {fsm, ide, terminal, processmanager, logmonitor}
 
+    # Your custom event handlers
+    message_fsm_steps = MessageFSMStepsEventHandler(
+        key='test'
+    )
+
+    # Terminal command handlers
     commands = TestCommands(bashrc=f'/home/{TAOENV.USER}/.bashrc')
     terminal.historymonitor.subscribe_callback(commands.callback)
+
+    # Example terminal command callback
     terminal.historymonitor.subscribe_callback(cenator)
 
     try:
         IOLoop.instance().start()
     finally:
+        eventhandlers = {fsm, ide, terminal, processmanager, logmonitor, message_fsm_steps}
         for eh in eventhandlers:
             eh.cleanup()