green.zmq: support RCVTIMEO (receive timeout)

https://github.com/eventlet/eventlet/issues/282
https://github.com/eventlet/eventlet/pull/283

AUTHORS

@@ -143,3 +143,4 @@ Thanks To
 * Matthew D. Pagel
 * Matt Yule-Bennett
 * Artur Stawiarski
+* Tal Wrii

eventlet/green/zmq.py

@@ -95,11 +95,14 @@ class _BlockedThread(object):
 
     __bool__ = __nonzero__
 
-    def block(self):
+    def block(self, deadline=None):
         if self._blocked_thread is not None:
             raise Exception("Cannot block more than one thread on one BlockedThread")
         self._blocked_thread = greenlet.getcurrent()
 
+        if deadline is not None:
+            self._hub.schedule_call_local(deadline - self._hub.clock(), self.wake)
+
         try:
             self._hub.switch()
         finally:
@@ -245,6 +248,7 @@ class Socket(_Socket):
                                                       event,
                                                       lambda _: None,
                                                       lambda: None)
+        self.__dict__['_eventlet_clock'] = hub.clock
 
     @_wraps(_Socket.close)
     def close(self, linger=None):
@@ -376,6 +380,16 @@ class Socket(_Socket):
             self._eventlet_recv_event.wake()
             return msg
 
+        deadline = None
+        if hasattr(__zmq__, 'RCVTIMEO'):
+            sock_timeout = self.getsockopt(__zmq__.RCVTIMEO)
+            if sock_timeout == -1:
+                pass
+            elif sock_timeout > 0:
+                deadline = self._eventlet_clock() + sock_timeout / 1000.0
+            else:
+                raise ValueError(sock_timeout)
+
         flags |= NOBLOCK
         with self._eventlet_recv_lock:
             while True:
@@ -383,7 +397,12 @@ class Socket(_Socket):
                     return _Socket_recv(self, flags, copy, track)
                 except ZMQError as e:
                     if e.errno == EAGAIN:
-                        self._eventlet_recv_event.block()
+                        # zmq in its wisdom decided to reuse EAGAIN for timeouts
+                        if deadline is not None and self._eventlet_clock() > deadline:
+                            e.is_timeout = True
+                            raise
+
+                        self._eventlet_recv_event.block(deadline=deadline)
                     else:
                         raise
                 finally:

tests/zmq_test.py

@@ -597,3 +597,16 @@ def test_recv_json_no_args():
     with clean_pair(zmq.REQ, zmq.REP) as (s1, s2, _):
         eventlet.spawn(s1.send_json, {})
         s2.recv_json()
+
+
+@tests.skip_unless(zmq_supported)
+def test_recv_timeout():
+    # https://github.com/eventlet/eventlet/issues/282
+    with clean_pair(zmq.PUB, zmq.SUB) as (_, sub, _):
+        sub.setsockopt(zmq.RCVTIMEO, 100)
+        try:
+            with eventlet.Timeout(1, False):
+                sub.recv()
+            assert False
+        except zmq.ZMQError as e:
+            assert eventlet.is_timeout(e)