Initial work on dynamic service bot joining / parting (#265)

coremods/service_support.py

@@ -73,9 +73,8 @@ def spawn_service(irc, source, command, args):
         log.debug('(%s) spawn_service: irc.pseudoclient set to UID %s', irc.name, u)
         irc.pseudoclient = userobj
 
-    channels = set(irc.serverdata.get(name+'_channels', [])) | set(irc.serverdata.get('channels', [])) | \
+    # Enumerate & join network defined channels.
-               sbot.extra_channels.get(irc.name, set())
+    sbot.join(irc, sbot.get_persistent_channels(irc))
-    sbot.join(irc, channels)
 
 utils.add_hook(spawn_service, 'PYLINK_NEW_SERVICE')
 
@@ -121,12 +120,43 @@ def handle_kill(irc, source, command, args):
 
 utils.add_hook(handle_kill, 'KILL')
 
+def handle_join(irc, source, command, args):
+    """Monitors channel joins for dynamic service bot joining."""
+    channel = args['channel']
+    users = irc.channels[channel].users
+    for servicename, sbot in world.services.items():
+        if channel in sbot.get_persistent_channels(irc) and \
+                sbot.uids.get(irc.name) not in users:
+            log.debug('(%s) Dynamically joining service %r to channel %r.', irc.name, servicename, channel)
+            sbot.join(irc, channel)
+utils.add_hook(handle_join, 'JOIN')
+utils.add_hook(handle_join, 'PYLINK_SERVICE_JOIN')
+
+def _services_dynamic_part(irc, channel):
+    """Dynamically removes service bots from empty channels."""
+    # If all remaining users in the channel are service bots, make them all part.
+    if all(irc.is_internal_client(u) for u in irc.channels[channel].users):
+        for u in irc.channels[channel].users.copy():
+            sbot = irc.get_service_bot(u)
+            if sbot:
+                log.debug('(%s) Dynamically parting service %r from channel %r.', irc.name, sbot.name, channel)
+                irc.part(u, channel)
+        return True
+
+def handle_part(irc, source, command, args):
+    """Monitors channel joins for dynamic service bot joining."""
+    for channel in args['channels']:
+        _services_dynamic_part(irc, channel)
+utils.add_hook(handle_part, 'PART')
+
 def handle_kick(irc, source, command, args):
     """Handle KICKs to the PyLink service bots, rejoining channels as needed."""
-    kicked = args['target']
     channel = args['channel']
+    # Skip autorejoin routines if the channel is now empty.
+    if not _services_dynamic_part(irc, channel):
+        kicked = args['target']
         sbot = irc.get_service_bot(kicked)
-    if sbot:
+        if sbot and channel in sbot.get_persistent_channels(irc):
             sbot.join(irc, channel)
 utils.add_hook(handle_kick, 'KICK')
 
@@ -142,7 +172,7 @@ def handle_commands(irc, source, command, args):
 utils.add_hook(handle_commands, 'PRIVMSG')
 
 # Register the main PyLink service. All command definitions MUST go after this!
-# TODO: be more specific, and possibly allow plugins to modify this to mention
+# TODO: be more specific in description, and possibly allow plugins to modify this to mention
 # their features?
 mydesc = "\x02PyLink\x02 provides extended network services for IRC."
 utils.register_service('pylink', default_nick="PyLink", desc=mydesc, manipulatable=True)

plugins/relay.py

@@ -539,23 +539,19 @@ def remove_channel(irc, channel):
     if irc is None:
         return
 
-    if channel not in map(str.lower, irc.serverdata.get('channels', [])):
+    world.services['pylink'].dynamic_channels[irc.name].discard(channel)
-        world.services['pylink'].extra_channels[irc.name].discard(channel)
-        if irc.pseudoclient:
-            irc.part(irc.pseudoclient.uid, channel, 'Channel delinked.')
 
     relay = get_relay(irc, channel)
     if relay and channel in irc.channels:
         for user in irc.channels[channel].users.copy():
-            if not is_relay_client(irc, user):
+            # Relay a /part of all local users.
+            if not is_internal_client(irc, user):
                 relay_part(irc, channel, user)
-            # Don't ever part the main client from any of its autojoin channels.
             else:
-                if user == irc.pseudoclient.uid and channel in \
+                # Part and quit all relay clients.
-                        irc.serverdata.get('channels', []):
+                if irc.get_service_bot(user):  # ...but ignore service bots
                     continue
                 irc.part(user, channel, 'Channel delinked.')
-                # Don't ever quit it either...
                 if user != irc.pseudoclient.uid and not irc.users[user].channels:
                     remoteuser = get_orig_user(irc, user)
                     del relayusers[remoteuser][irc.name]

utils.py

@@ -13,7 +13,7 @@ import collections
 import argparse
 
 from .log import log
-from . import world, conf
+from . import world, conf, structures
 
 # Load the protocol and plugin packages.
 from pylinkirc import protocols, plugins
@@ -152,9 +152,10 @@ class ServiceBot():
         # spawned.
         self.uids = {}
 
-        # Track what channels other than those defined in the config
+        # Track plugin-defined persistent channels. The bot will leave them if they're empty,
-        # that the bot should join by default.
+        # and rejoin whenever someone else does.
-        self.extra_channels = collections.defaultdict(set)
+        self.dynamic_channels = structures.KeyedDefaultdict(lambda netname:
+            structures.IRCCaseInsensitiveSet(world.networkobjects[netname]))
 
         # Service description, used in the default help command if one is given.
         self.desc = desc
@@ -183,9 +184,14 @@ class ServiceBot():
         else:
             raise NotImplementedError("Network specific plugins not supported yet.")
 
-    def join(self, irc, channels, autojoin=True):
+    def join(self, irc, channels, ignore_empty=True):
         """
-        Joins the given service bot to the given channel(s).
+        Joins the given service bot to the given channel(s). channels can be an iterable of channel names
+        or the name of a single channel (str).
+
+        The ignore_empty option sets whether we should skip joining empty channels and join them
+        later when we see someone else join. This is option is disabled on networks where we cannot
+        monitor channel state.
         """
 
         if isinstance(irc, str):
@@ -198,10 +204,6 @@ class ServiceBot():
             channels = [channels]
         channels = set(channels)
 
-        if autojoin:
-            log.debug('(%s/%s) Adding channels %s to autojoin', netname, self.name, channels)
-            self.extra_channels[netname] |= channels
-
         # If the network was given as a string, look up the Irc object here.
         try:
             irc = world.networkobjects[netname]
@@ -209,6 +211,10 @@ class ServiceBot():
             log.debug('(%s/%s) Skipping join(), IRC object not initialized yet', netname, self.name)
             return
 
+        if irc.has_cap('visible-state-only'):
+            # Disable dynamic channel joining on networks where we can't monitor channels for joins.
+            ignore_empty = False
+
         try:
             u = self.uids[irc.name]
         except KeyError:
@@ -221,10 +227,16 @@ class ServiceBot():
 
         for chan in channels:
             if irc.is_channel(chan):
-                if chan in irc.channels and u in irc.channels[chan].users:
+                if chan in irc.channels:
-                    log.debug('(%s) Skipping join of services %s to channel %s - it is already present', irc.name, self.name, chan)
+                    if u in irc.channels[chan].users:
+                        log.debug('(%s) Skipping join of service %r to channel %r - it is already present', irc.name, self.name, chan)
                         continue
+                elif ignore_empty:
+                    log.debug('(%s) Skipping joining service %r to empty channel %r', irc.name, self.name, chan)
+                    continue
+
                 log.debug('(%s) Joining services %s to channel %s with modes %r', irc.name, self.name, chan, joinmodes)
+
                 if joinmodes:  # Modes on join were specified; use SJOIN to burst our service
                     irc.proto.sjoin(irc.sid, chan, [(joinmodes, u)])
                 else:
@@ -387,6 +399,15 @@ class ServiceBot():
         sbconf = conf.conf.get(self.name, {})
         return irc.serverdata.get("%s_realname" % self.name) or sbconf.get('realname') or conf.conf['pylink'].get('realname') or self.name
 
+    def get_persistent_channels(self, irc):
+        """
+        Returns a set of persistent channels for the IRC network.
+        """
+        channels = self.dynamic_channels[irc.name].copy()
+        channels |= set(irc.serverdata.get(self.name+'_channels', []))
+        channels |= set(irc.serverdata.get('channels', []))
+        return channels
+
     def _show_command_help(self, irc, command, private=False, shortform=False):
         """
         Shows help for the given command.