- Corrected param name

- Added variable for repetitively accessed dictionary value
- extended if statement to also check if "sub" is not None to see if the subscription has actually been made.
- Added on_remote_leave to empty dictionary of forwarded subscriptions
- extended if statement to also check if "reg" is not None to see if the registration has actually been made.
- Made "create forwarding registration" log debug level to match the subscription one. This is expected functionality and there can be large amounts of registrations which would cause log spam.

Author: David Ellis

crossbar/worker/rlink.py

@@ -74,23 +74,26 @@ def on_subscription_create(sub_session, sub_details, details=None):
             The handler will then also subscribe on the other router, and when receiving
             events, re-publish those on this router.
 
-            :param sub_id:
+            :param sub_session:
             :param sub_details:
             :param details:
             :return:
             """
             if sub_details["uri"].startswith("wamp."):
                 return
 
-            if sub_details["id"] in self._subs:
-                # this should not happen actually, but not sure ..
+            sub_id = sub_details["id"]
+
+            if sub_id in self._subs and self._subs[sub_id]["sub"]:
+                # This will happen if, partway through the subscription process, the RLink disconnects
                 self.log.error('on_subscription_create: sub ID {sub_id} already in map {method}',
-                               sub_id=sub_details["id"],
+                               sub_id=sub_id,
                                method=hltype(BridgeSession._setup_event_forwarding))
                 return
 
-            self._subs[sub_details["id"]] = sub_details
-            self._subs[sub_details["id"]]["sub"] = None
+            if sub_id not in self._subs:
+                self._subs[sub_id] = sub_details
+                self._subs[sub_id]["sub"] = None
 
             uri = sub_details['uri']
             ERR_MSG = [None]
@@ -162,17 +165,17 @@ def on_event(*args, **kwargs):
                         uri))
                 return
 
-            if sub_details["id"] not in self._subs:
+            if sub_id not in self._subs:
                 self.log.info("subscription already gone: {uri}", uri=sub_details['uri'])
                 yield sub.unregister()
             else:
-                self._subs[sub_details["id"]]["sub"] = sub
+                self._subs[sub_id]["sub"] = sub
 
             self.log.debug(
                 "created forwarding subscription: me={me} other={other} sub_id={sub_id} sub_details={sub_details} details={details} sub_session={sub_session}",
                 me=self._session_id,
                 other=other,
-                sub_id=sub_details["id"],
+                sub_id=sub_id,
                 sub_details=sub_details,
                 details=details,
                 sub_session=sub_session,
@@ -222,12 +225,21 @@ def forward_current_subs():
         def on_remote_join(_session, _details):
             yield forward_current_subs()
 
+        def on_remote_leave(_session, _details):
+            # The remote session has ended, clear subscription records.
+            # Clearing this dictionary helps avoid the case where
+            # local procedures are not subscribed on the remote leg
+            # on reestablishment of remote session.
+            # See: https://github.com/crossbario/crossbar/issues/1909
+            self._subs = {}
+
         if self.IS_REMOTE_LEG:
             yield forward_current_subs()
         else:
             # from the local leg, don't try to forward events on the
             # remote leg unless the remote session is established.
             other.on('join', on_remote_join)
+            other.on('leave', on_remote_leave)
 
         # listen to when new subscriptions are created on the local router
         yield self.subscribe(on_subscription_create,
@@ -267,15 +279,18 @@ def on_registration_create(reg_session, reg_details, details=None):
             if reg_details['uri'].startswith("wamp."):
                 return
 
-            if reg_details['id'] in self._regs:
-                # this should not happen actually, but not sure ..
+            reg_id = reg_details["id"]
+
+            if reg_id in self._regs and self._regs[reg_id]["reg"]:
+                # This will happen if, partway through the registration process, the RLink disconnects
                 self.log.error('on_registration_create: reg ID {reg_id} already in map {method}',
-                               reg_id=reg_details['id'],
+                               reg_id=reg_id,
                                method=hltype(BridgeSession._setup_invocation_forwarding))
                 return
 
-            self._regs[reg_details['id']] = reg_details
-            self._regs[reg_details['id']]['reg'] = None
+            if reg_id not in self._regs:
+                self._regs[reg_id] = reg_details
+                self._regs[reg_id]['reg'] = None
 
             uri = reg_details['uri']
             ERR_MSG = [None]
@@ -365,17 +380,17 @@ def on_call(*args, **kwargs):
             # on the "other" router, *this* router may have already
             # un-registered. If that happened, our registration will
             # be gone, so we immediately un-register on the other side
-            if reg_details['id'] not in self._regs:
+            if reg_id not in self._regs:
                 self.log.info("registration already gone: {uri}", uri=reg_details['uri'])
                 yield reg.unregister()
             else:
-                self._regs[reg_details['id']]['reg'] = reg
+                self._regs[reg_id]['reg'] = reg
 
-            self.log.info(
+            self.log.debug(
                 "created forwarding registration: me={me} other={other} reg_id={reg_id} reg_details={reg_details} details={details} reg_session={reg_session}",
                 me=self._session_id,
                 other=other._session_id,
-                reg_id=reg_details['id'],
+                reg_id=reg_id,
                 reg_details=reg_details,
                 details=details,
                 reg_session=reg_session,