X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/e621ee479da9664e912a6e74f24342877533872c..956c3a765e3794a291376cbb5a2ee9ec6ef4560b:/sdk/python/arvados/events.py

diff --git a/sdk/python/arvados/events.py b/sdk/python/arvados/events.py
index b1872002eb..df5b3e7dee 100644
--- a/sdk/python/arvados/events.py
+++ b/sdk/python/arvados/events.py
@@ -28,6 +28,7 @@ class EventClient(WebSocketClient):
         super(EventClient, self).__init__(url, ssl_options=ssl_options)
         self.filters = filters
         self.on_event = on_event
+        self.stop = threading.Event()
         self.last_log_id = last_log_id
 
     def opened(self):
@@ -36,12 +37,24 @@ class EventClient(WebSocketClient):
     def received_message(self, m):
         self.on_event(json.loads(str(m)))
 
-    def close_connection(self):
-        try:
-            self.sock.shutdown(socket.SHUT_RDWR)
-            self.sock.close()
-        except:
-            pass
+    def closed(self, code, reason=None):
+        self.stop.set()
+
+    def close(self, code=1000, reason=''):
+        """Close event client and wait for it to finish."""
+
+        # parent close() method sends a asynchronous "closed" event to the server
+        super(EventClient, self).close(code, reason)
+
+        # if server doesn't respond by finishing the close handshake, we'll be
+        # stuck in limbo forever.  We don't need to wait for the server to
+        # respond to go ahead and actually close the socket.
+        self.close_connection()
+
+        # wait for websocket thread to finish up (closed() is called by
+        # websocket thread in as part of terminate())
+        while not self.stop.is_set():
+            self.stop.wait(1)
 
     def subscribe(self, filters, last_log_id=None):
         m = {"method": "subscribe", "filters": filters}
@@ -53,7 +66,7 @@ class EventClient(WebSocketClient):
         self.send(json.dumps({"method": "unsubscribe", "filters": filters}))
 
 class PollClient(threading.Thread):
-    def __init__(self, api, filters, on_event, poll_time):
+    def __init__(self, api, filters, on_event, poll_time, last_log_id):
         super(PollClient, self).__init__()
         self.api = api
         if filters:
@@ -64,27 +77,35 @@ class PollClient(threading.Thread):
         self.poll_time = poll_time
         self.daemon = True
         self.stop = threading.Event()
+        self.last_log_id = last_log_id
 
     def run(self):
         self.id = 0
-        for f in self.filters:
-            items = self.api.logs().list(limit=1, order="id desc", filters=f).execute()['items']
-            if items:
-                if items[0]['id'] > self.id:
-                    self.id = items[0]['id']
+        if self.last_log_id != None:
+            self.id = self.last_log_id
+        else:
+            for f in self.filters:
+                items = self.api.logs().list(limit=1, order="id desc", filters=f).execute()['items']
+                if items:
+                    if items[0]['id'] > self.id:
+                        self.id = items[0]['id']
 
         self.on_event({'status': 200})
 
         while not self.stop.isSet():
             max_id = self.id
+            moreitems = False
             for f in self.filters:
-                items = self.api.logs().list(order="id asc", filters=f+[["id", ">", str(self.id)]]).execute()['items']
-                for i in items:
+                items = self.api.logs().list(order="id asc", filters=f+[["id", ">", str(self.id)]]).execute()
+                for i in items["items"]:
                     if i['id'] > max_id:
                         max_id = i['id']
                     self.on_event(i)
+                if items["items_available"] > len(items["items"]):
+                    moreitems = True
             self.id = max_id
-            self.stop.wait(self.poll_time)
+            if not moreitems:
+                self.stop.wait(self.poll_time)
 
     def run_forever(self):
         # Have to poll here, otherwise KeyboardInterrupt will never get processed.
@@ -92,6 +113,8 @@ class PollClient(threading.Thread):
             self.stop.wait(1)
 
     def close(self):
+        """Close poll client and wait for it to finish."""
+
         self.stop.set()
         try:
             self.join()
@@ -115,16 +138,21 @@ def _subscribe_websocket(api, filters, on_event, last_log_id=None):
     if not endpoint:
         raise errors.FeatureNotEnabledError(
             "Server does not advertise a websocket endpoint")
-    uri_with_token = "{}?api_token={}".format(endpoint, api.api_token)
-    client = EventClient(uri_with_token, filters, on_event, last_log_id)
-    ok = False
     try:
-        client.connect()
-        ok = True
-        return client
-    finally:
-        if not ok:
-            client.close_connection()
+        uri_with_token = "{}?api_token={}".format(endpoint, api.api_token)
+        client = EventClient(uri_with_token, filters, on_event, last_log_id)
+        ok = False
+        try:
+            client.connect()
+            ok = True
+            return client
+        finally:
+            if not ok:
+                client.close_connection()
+    except:
+        _logger.warn("Failed to connect to websockets on %s" % endpoint)
+        raise
+
 
 def subscribe(api, filters, on_event, poll_fallback=15, last_log_id=None):
     """
@@ -147,6 +175,6 @@ def subscribe(api, filters, on_event, poll_fallback=15, last_log_id=None):
         return _subscribe_websocket(api, filters, on_event, last_log_id)
     except Exception as e:
         _logger.warn("Falling back to polling after websocket error: %s" % e)
-    p = PollClient(api, filters, on_event, poll_fallback)
+    p = PollClient(api, filters, on_event, poll_fallback, last_log_id)
     p.start()
     return p