Renamed and refactored flooding protection helper

src_coffee/server/clientflooding.coffee

-
-## Abstraction to store and recognize flooding by a client.
-##
-class ClientFloodingProtection
-    rating: []      # Array of: [*{'timestamp', 'size'}]
-
-    # Describes a rate limit of 1mb/s:
-    limit: 1048576  # Maximum number of bytes/characters
-    interval: 1000  # Interval in milliseconds
-
-    addRatingEntry: (size) ->
-        newEntry = 
-            timestamp: Date.now()
-            size: size
-        @rating.push(newEntry)
-        return newEntry
-
-    # Removes outdated entries, computes combined size, and compares with limit variable.
-    # Returns true if client is NOT flooding, returns false if it need to disconnect.
-    evalRating: ->
-        # totalSize in bytes in case of underlying Buffer value, in number of characters for strings. 
-        # Actual byte size in case of strings might be variable => not reliable.
-        totalSize = null
-
-        newRating = []
-
-        # loop
-        i = @rating.length - 1
-        while i >= 0
-            if Date.now() - @rating[i].timestamp < @interval
-                newRating.push @rating[i]
-            i -= 1
-
-        @rating = newRating
-
-        # loop
-        totalSize = 0
-        i = newRating.length - 1
-        while i >= 0
-            totalSize += newRating[i].timestamp
-            i -= 1
-
-        return (totalSize <= @limit)
-
-
-    _example: ->
-        # Assume connection variable already exists and has a readable stream interface
-        connection.on 'data', (chunk) =>
-            @addRatingEntry chunk.length
-            if @evalRating()
-                # Continue processing chunk.
-            else
-                # Disconnect due to flooding.
-            return
-
-
-
-
-
-## Export class
-module.exports = ClientFloodingProtection
-

src_coffee/server/clientrating.coffee

+
+## Abstraction to store and recognize flooding by a client.
+##
+class ClientFloodingRating
+    clientSocket: null
+    ratingEntries: null   # Array of: [*{'timestamp', 'size'}]
+
+    # Describes a rate limit of 1mb/s:
+    LIMIT_SIZE = 1048576  # Maximum number of bytes/characters
+    TIME_INTERVAL = 1000  # Interval in milliseconds
+
+    constructor: (@clientSocket) ->
+        @ratingEntries = []
+
+    _addRatingEntry: (size) ->
+        newEntry = 
+            timestamp: Date.now()
+            size: size
+        @ratingEntries.push(newEntry)
+        return newEntry
+
+    _getEntriesWithinInterval: ->
+        # Collect entries created within interval
+        intervalEntries = []
+        nowTimestamp = Date.now()
+
+        for currEntry in @ratingEntries by -1
+            if nowTimestamp - currEntry.timestamp < TIME_INTERVAL  # Must be younger than interval time
+                intervalEntries.push(currEntry)
+
+        return intervalEntries
+
+    _getCalculatedTotalSize: (entries) ->
+        totalSize = 0
+        for currEntry in entries by 1
+            totalSize += currEntry.size
+        return totalSize
+
+
+    checkForFlooding: (chunk) ->
+        @_addRatingEntry(chunk.length)
+        
+        # Remove outdated entries / update array
+        @ratingEntries = @_getEntriesWithinInterval()
+
+        # Sum up size of entries in interval
+        totalSize = @_getCalculatedTotalSize(@ratingEntries)
+
+        # Check limit
+        if totalSize > LIMIT_SIZE
+            clientSocket.disconnect()  # TODO: Disconnect due to flooding.
+            return false
+
+        return true
+
+    destroy: ->
+        @clientSocket = null
+        @ratingEntries = null
+
+
+
+## Export class
+module.exports = ClientFloodingProtection
+

src_coffee/webclient/chat_controller.coffee

 # Controller class to handle communication with server
 class this.ChatController
-
     socketHandler: null
-    CHANNEL_NAME_MIN_LENGTH = 4
-    CHANNEL_NAME_MAX_LENGTH = 20
-    CHANNEL_PASSWORD_MIN_LENGTH = 5
-
     serverIP: ''
     serverPort: 0
     instanceData: {}