10535: Fix race-to-deadlock bugs in tests.test_events: use threading.Event, not threa...

diff --git a/sdk/python/tests/test_events.py b/sdk/python/tests/test_events.py
index f2cdba28c775a523bc178052644cb4a76dac2771..0199724339b76f0fb37e5af89c8d62c53f332711 100644 (file)
--- a/sdk/python/tests/test_events.py
+++ b/sdk/python/tests/test_events.py
@@ -17,6 +17,8 @@ class WebsocketTest(run_test_server.TestCaseWithServers):
     TIME_FUTURE = time.time()+3600
     MOCK_WS_URL = 'wss://[{}]/'.format(arvados_testutil.TEST_HOST)
 
+    TEST_TIMEOUT = 10.0
+
     def setUp(self):
         self.ws = None
 
@@ -262,20 +264,16 @@ class WebsocketTest(run_test_server.TestCaseWithServers):
 
     @mock.patch('arvados.events._EventClient')
     def test_run_forever_survives_reconnects(self, websocket_client):
-        connection_cond = threading.Condition()
-        def ws_connect():
-            with connection_cond:
-                connection_cond.notify_all()
-        websocket_client().connect.side_effect = ws_connect
+        connected = threading.Event()
+        websocket_client().connect.side_effect = connected.set
         client = arvados.events.EventClient(
             self.MOCK_WS_URL, [], lambda event: None, None)
-        with connection_cond:
-            forever_thread = threading.Thread(target=client.run_forever)
-            forever_thread.start()
-            # Simulate an unexpected disconnect, and wait for reconnect.
-            close_thread = threading.Thread(target=client.on_closed)
-            close_thread.start()
-            connection_cond.wait()
+        forever_thread = threading.Thread(target=client.run_forever)
+        forever_thread.start()
+        # Simulate an unexpected disconnect, and wait for reconnect.
+        close_thread = threading.Thread(target=client.on_closed)
+        close_thread.start()
+        self.assertTrue(connected.wait(timeout=self.TEST_TIMEOUT))
         close_thread.join()
         run_forever_alive = forever_thread.is_alive()
         client.close()
@@ -285,7 +283,10 @@ class WebsocketTest(run_test_server.TestCaseWithServers):
 
 
 class PollClientTestCase(unittest.TestCase):
+    TEST_TIMEOUT = 10.0
+
     class MockLogs(object):
+
         def __init__(self):
             self.logs = []
             self.lock = threading.Lock()
@@ -300,12 +301,11 @@ class PollClientTestCase(unittest.TestCase):
                 self.logs = []
             return {'items': retval, 'items_available': len(retval)}
 
-
     def setUp(self):
         self.logs = self.MockLogs()
         self.arv = mock.MagicMock(name='arvados.api()')
         self.arv.logs().list().execute.side_effect = self.logs.return_list
-        self.callback_cond = threading.Condition()
+        self.callback_called = threading.Event()
         self.recv_events = []
 
     def tearDown(self):
@@ -313,9 +313,8 @@ class PollClientTestCase(unittest.TestCase):
             self.client.close(timeout=None)
 
     def callback(self, event):
-        with self.callback_cond:
-            self.recv_events.append(event)
-            self.callback_cond.notify_all()
+        self.recv_events.append(event)
+        self.callback_called.set()
 
     def build_client(self, filters=None, callback=None, last_log_id=None, poll_time=99):
         if filters is None:
@@ -333,11 +332,11 @@ class PollClientTestCase(unittest.TestCase):
         test_log = {'id': 12345, 'testkey': 'testtext'}
         self.logs.add({'id': 123})
         self.build_client(poll_time=.01)
-        with self.callback_cond:
-            self.client.start()
-            self.callback_cond.wait()
-            self.logs.add(test_log.copy())
-            self.callback_cond.wait()
+        self.client.start()
+        self.assertTrue(self.callback_called.wait(self.TEST_TIMEOUT))
+        self.callback_called.clear()
+        self.logs.add(test_log.copy())
+        self.assertTrue(self.callback_called.wait(self.TEST_TIMEOUT))
         self.client.close(timeout=None)
         self.assertIn(test_log, self.recv_events)
 
@@ -345,9 +344,8 @@ class PollClientTestCase(unittest.TestCase):
         client_filter = ['kind', '=', 'arvados#test']
         self.build_client()
         self.client.subscribe([client_filter[:]])
-        with self.callback_cond:
-            self.client.start()
-            self.callback_cond.wait()
+        self.client.start()
+        self.assertTrue(self.callback_called.wait(self.TEST_TIMEOUT))
         self.client.close(timeout=None)
         self.assertTrue(self.was_filter_used(client_filter))
 
@@ -362,11 +360,10 @@ class PollClientTestCase(unittest.TestCase):
 
     def test_run_forever(self):
         self.build_client()
-        with self.callback_cond:
-            self.client.start()
-            forever_thread = threading.Thread(target=self.client.run_forever)
-            forever_thread.start()
-            self.callback_cond.wait()
+        self.client.start()
+        forever_thread = threading.Thread(target=self.client.run_forever)
+        forever_thread.start()
+        self.assertTrue(self.callback_called.wait(self.TEST_TIMEOUT))
         self.assertTrue(forever_thread.is_alive())
         self.client.close()
         forever_thread.join()