update naming from Set -> Map

services/real-time/app/coffee/ChannelManager.coffee

@@ -2,7 +2,7 @@ logger = require 'logger-sharelatex'
 metrics = require "metrics-sharelatex"
 settings = require "settings-sharelatex"
 
-ClientMap = new Map() # for each redis client, stores a Map of subscribed channels (channelname -> subscribe promise)
+ClientMap = new Map() # for each redis client, store a Map of subscribed channels (channelname -> subscribe promise)
 
 # Manage redis pubsub subscriptions for individual projects and docs, ensuring
 # that we never subscribe to a channel multiple times. The socket.io side is
@@ -10,34 +10,34 @@ ClientMap = new Map() # for each redis client, stores a Map of subscribed channe
 
 module.exports = ChannelManager =
     getClientMapEntry: (rclient) ->
-        # return the rclient channel set if it exists, otherwise create and
-        # return an empty set for the client.
+        # return the per-client channel map if it exists, otherwise create and
+        # return an empty map for the client.
         ClientMap.get(rclient) || ClientMap.set(rclient, new Map()).get(rclient)
 
     subscribe: (rclient, baseChannel, id) ->
-        existingChannelSet = @getClientMapEntry(rclient)
+        clientChannelMap = @getClientMapEntry(rclient)
         channel = "#{baseChannel}:#{id}"
-        if existingChannelSet.has(channel)
-            logger.error {channel}, "already subscribed - shouldn't happen"
-            # return the subscribe promise, so we can wait for it to resolve
-            return existingChannelSet.get(channel)
+        if clientChannelMap.has(channel)
+            logger.warn {channel}, "subscribe already actioned"
+            # return the existing subscribe promise, so we can wait for it to resolve
+            return clientChannelMap.get(channel)
         else
             # get the subscribe promise and return it, the actual subscribe
             # completes in the background
             subscribePromise = rclient.subscribe channel
-            existingChannelSet.set(channel, subscribePromise)
+            clientChannelMap.set(channel, subscribePromise)
             logger.log {channel}, "subscribed to new channel"
             metrics.inc "subscribe.#{baseChannel}"
             return subscribePromise
 
     unsubscribe: (rclient, baseChannel, id) ->
-        existingChannelSet = @getClientMapEntry(rclient)
+        clientChannelMap = @getClientMapEntry(rclient)
         channel = "#{baseChannel}:#{id}"
-        if !existingChannelSet.has(channel)
+        if !clientChannelMap.has(channel)
             logger.error {channel}, "not subscribed - shouldn't happen"
         else
             rclient.unsubscribe channel # completes in the background
-            existingChannelSet.delete(channel)
+            clientChannelMap.delete(channel)
             logger.log {channel}, "unsubscribed from channel"
             metrics.inc "unsubscribe.#{baseChannel}"
 

services/real-time/test/unit/coffee/ChannelManagerTests.coffee

@@ -11,7 +11,7 @@ describe 'ChannelManager', ->
 		@ChannelManager = SandboxedModule.require modulePath, requires:
 			"settings-sharelatex": @settings = {}
 			"metrics-sharelatex": @metrics = {inc: sinon.stub()}
-			"logger-sharelatex": @logger = { log: sinon.stub(), error: sinon.stub() }
+			"logger-sharelatex": @logger = { log: sinon.stub(), warn: sinon.stub(), error: sinon.stub() }
 	
 	describe "subscribe", ->