Push context management down into the protocol instance.

labrad/backend.py

@@ -10,7 +10,7 @@
 from concurrent.futures import Future
 from twisted.internet import defer, reactor
 
-from labrad import auth, constants as C, support, thread, types as T
+from labrad import constants as C, support, thread, types as T
 from labrad.wrappers import getConnection
 
 
@@ -32,12 +32,6 @@ def __init__(self, cxn, spawn_kw=None):
         self._spawn_kw = spawn_kw
         self._connected = threading.Event()
         self._connected.set()
-        self._nextContext = 1
-
-        # This connection can be shared between multiple threads with
-        # separate Client objects.  Access to mutable state needs to
-        # be protected by a lock.
-        self._lock = threading.Lock()
 
         # Setup a coroutine that will clear the connected flag when the
         # connection is lost. We launch this but do not wait for the result of
@@ -68,10 +62,7 @@ def spawn(self):
 
     def context(self):
         """Create a new context for use with this connection"""
-        with self._lock:
-            ctx = 0, self._nextContext
-            self._nextContext += 1
-            return ctx
+        return _call_future(self.cxn.context).result()
 
     def sendRequest(self, target, records, *args, **kw):
         return _call_future(self.cxn.sendRequest, target, records, *args, **kw)

labrad/protocol.py

@@ -37,6 +37,7 @@ class LabradProtocol(protocol.Protocol):
 
     def __init__(self):
         self.disconnected = False
+        self._next_context = 1
         self._nextRequest = 1
         self.pool = set()
         self.requests = {}
@@ -65,6 +66,12 @@ def set_address(self, host, port):
         self.host = host
         self.port = port
 
+    def context(self):
+        """Create a new communication context for this connection."""
+        context = (0, self._next_context)
+        self._next_context += 1
+        return context
+
     # network events
     def connectionMade(self):
         # set the SO_KEEPALIVE option on all connections

labrad/wrappers.py

@@ -428,7 +428,6 @@ def __init__(self, prot):
         self._cache = {}
         self._cxn = prot
         self._mgr = manager.AsyncManager(self._cxn)
-        self._next_context = 1
         self._refreshLock = defer.DeferredLock()
 
     _staticAttrs = ['servers', 'refresh', 'context']
@@ -548,9 +547,7 @@ def _delServer(self, name):
 
     def context(self):
         """Create a new communication context for this connection."""
-        context = (0, self._next_context)
-        self._next_context += 1
-        return context
+        return self._cxn.context()
 
     def __getitem__(self, key):
         return self.servers[key]