backporting stuff from twisted 10.2.0

websocket.py

@@ -21,9 +21,7 @@
 
 from twisted.internet import interfaces
 from twisted.python import log
-from twisted.web._newclient import makeStatefulDispatcher
 from twisted.web.http import datetimeToString
-from twisted.web.http import _IdentityTransferDecoder
 from twisted.web.server import Request, Site, version, unquote
 from zope.interface import implements
 
@@ -42,6 +40,108 @@
 CONTROL_OPCODES = (OPCODE_CLOSE, OPCODE_PING, OPCODE_PONG)
 DATA_OPCODES = (OPCODE_TEXT, OPCODE_BINARY)
 
+# backported from twisted 11
+# twisted.web.http
+class _IdentityTransferDecoder(object):
+    """
+    Protocol for accumulating bytes up to a specified length.  This handles the
+    case where no I{Transfer-Encoding} is specified.
+
+    @ivar contentLength: Counter keeping track of how many more bytes there are
+        to receive.
+
+    @ivar dataCallback: A one-argument callable which will be invoked each
+        time application data is received.
+
+    @ivar finishCallback: A one-argument callable which will be invoked when
+        the terminal chunk is received.  It will be invoked with all bytes
+        which were delivered to this protocol which came after the terminal
+        chunk.
+    """
+    def __init__(self, contentLength, dataCallback, finishCallback):
+        self.contentLength = contentLength
+        self.dataCallback = dataCallback
+        self.finishCallback = finishCallback
+
+
+    def dataReceived(self, data):
+        """
+        Interpret the next chunk of bytes received.  Either deliver them to the
+        data callback or invoke the finish callback if enough bytes have been
+        received.
+
+        @raise RuntimeError: If the finish callback has already been invoked
+            during a previous call to this methood.
+        """
+        if self.dataCallback is None:
+            raise RuntimeError(
+                "_IdentityTransferDecoder cannot decode data after finishing")
+
+        if self.contentLength is None:
+            self.dataCallback(data)
+        elif len(data) < self.contentLength:
+            self.contentLength -= len(data)
+            self.dataCallback(data)
+        else:
+            # Make the state consistent before invoking any code belonging to
+            # anyone else in case noMoreData ends up being called beneath this
+            # stack frame.
+            contentLength = self.contentLength
+            dataCallback = self.dataCallback
+            finishCallback = self.finishCallback
+            self.dataCallback = self.finishCallback = None
+            self.contentLength = 0
+
+            dataCallback(data[:contentLength])
+            finishCallback(data[contentLength:])
+
+
+    def noMoreData(self):
+        """
+        All data which will be delivered to this decoder has been.  Check to
+        make sure as much data as was expected has been received.
+
+        @raise PotentialDataLoss: If the content length is unknown.
+        @raise _DataLoss: If the content length is known and fewer than that
+            many bytes have been delivered.
+
+        @return: C{None}
+        """
+        finishCallback = self.finishCallback
+        self.dataCallback = self.finishCallback = None
+        if self.contentLength is None:
+            finishCallback('')
+            raise PotentialDataLoss()
+        elif self.contentLength != 0:
+            raise _DataLoss()
+
+# Backported from twisted 11
+# twisted.web._newclient
+def makeStatefulDispatcher(name, template):
+    """
+    Given a I{dispatch} name and a function, return a function which can be
+    used as a method and which, when called, will call another method defined
+    on the instance and return the result.  The other method which is called is
+    determined by the value of the C{_state} attribute of the instance.
+
+    @param name: A string which is used to construct the name of the subsidiary
+        method to invoke.  The subsidiary method is named like C{'_%s_%s' %
+        (name, _state)}.
+
+    @param template: A function object which is used to give the returned
+        function a docstring.
+
+    @return: The dispatcher function.
+    """
+    def dispatcher(self, *args, **kwargs):
+        func = getattr(self, '_' + name + '_' + self._state, None)
+        if func is None:
+            raise RuntimeError(
+                "%r has no %s method in state %s" % (self, name, self._state))
+        return func(*args, **kwargs)
+    dispatcher.__doc__ = template.__doc__
+    return dispatcher
+
 
 class WebSocketRequest(Request):
     """
@@ -50,6 +150,20 @@ class WebSocketRequest(Request):
 
     ACCEPT_GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
 
+    # this is backported from twisted 10.2.0
+    def connectionLost(self, reason):
+        """
+        There is no longer a connection for this request to respond over.
+        Clean up anything which can't be useful anymore.
+        """
+        self._disconnected = True
+        self.channel = None
+        if self.content is not None:
+            self.content.close()
+        for d in self.notifications:
+            d.errback(reason)
+        self.notifications = []
+
     def process(self):
         connection = self.requestHeaders.getRawHeaders("Connection", [None])[0]
         upgrade = self.requestHeaders.getRawHeaders("Upgrade", [None])[0]