Add @at_start to trigger actions when plugins initialize

fixes attzonko#132

docs/decorators.rst

@@ -30,6 +30,17 @@ Direct messages::
 
 
 
+Actions just after plugin initilization ::
+
+    from mmpy_bot.bot import at_start
+
+
+    @at_start
+    def hello(client):
+        client.connect_websocket()
+        client.ping()
+
+
 Real case
 ---------
 
@@ -61,3 +72,10 @@ So now we can close access to some functions on plugins::
     def sms_to(message, name):
         # some code
         message.reply('Sms was sent to %s' % name)
+
+
+    @at_start
+    def hello(client):
+        team = client.api.get_team_by_name("TESTTEAM")
+        channel = client.api.get_channel_by_name("bot_test", team["id"])
+        client.channel_msg(channel["id"], "Hello, feels good to be alive!!")

docs/plugins.rst

@@ -11,6 +11,7 @@ To write a new plugin, simply create a function decorated by ``mmpy_bot.bot.resp
 
 - A function decorated with ``respond_to`` is called when a message matching the pattern is sent to the bot (direct message or @botname in a channel/group chat)
 - A function decorated with ``listen_to`` is called when a message matching the pattern is sent on a channel/group chat (not directly sent to the bot)
+- A function decorated with ``at_start`` is called as soon as the plugin is initialized (when the bot starts)
 
 .. code-block:: python
 
@@ -38,6 +39,13 @@ To write a new plugin, simply create a function decorated by ``mmpy_bot.bot.resp
         # Message is sent on the channel
         # message.send('I can help everybody!')
 
+    @at_start
+    def hello(client):
+        # Note that contrary to respond_to and listen_to @at_start
+        # receives a client object and not a message object
+        team = client.api.get_team_by_name("TESTTEAM")
+        channel = client.api.get_channel_by_name("bot_test", team["id"])
+        client.channel_msg(channel["id"], "Hello, feels good to be alive!!")
 
 To extract params from the message, you can use regular expression:
 

mmpy_bot/bot.py

@@ -35,6 +35,7 @@ def __init__(self):
 
     def run(self):
         self._plugins.init_plugins()
+        self._plugins.trigger_at_start(self._client)
         self._dispatcher.start()
         _thread.start_new_thread(self._keep_active, tuple())
         _thread.start_new_thread(self._run_jobs, tuple())
@@ -58,6 +59,7 @@ class PluginsManager(object):
         'respond_to': {},
         'listen_to': {}
     }
+    _at_start = []
 
     def __init__(self, plugins=None):
         self.plugins = plugins or []
@@ -107,6 +109,13 @@ def get_plugins(self, category, text):
         if not has_matching_plugin:
             yield None, None
 
+    def trigger_at_start(self, client):
+        for func in self._at_start:
+            try:
+                func(client)
+            except Exception as err:
+                logger.exception(err)
+
 
 class Matcher(object):
     """This allows us to map the same regex to multiple handlers."""
@@ -132,3 +141,14 @@ def respond_to(regexp, flags=0):
 
 def listen_to(regexp, flags=0):
     return get_wrapper('listen_to', regexp, flags)
+
+
+def at_start():
+    def wrapper(func):
+        PluginsManager._at_start.append(func)
+        logger.info(
+            'registered %s plugin "%s"',
+            "at_start", func.__name__)
+        return func
+
+    return wrapper