Initial checkin of gRPC to third_party/

third_party/grpc/src/python/grpcio/tests/unit/beta/_connectivity_channel_test.py

Index: third_party/grpc/src/python/grpcio/tests/unit/beta/_connectivity_channel_test.py
diff --git a/third_party/grpc/src/python/grpcio/tests/unit/beta/_connectivity_channel_test.py b/third_party/grpc/src/python/grpcio/tests/unit/beta/_connectivity_channel_test.py
new file mode 100644
index 0000000000000000000000000000000000000000..5dc87206394968e60ccea208b851c1d2534f91fc
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+++ b/third_party/grpc/src/python/grpcio/tests/unit/beta/_connectivity_channel_test.py
@@ -0,0 +1,191 @@
+# Copyright 2015, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Tests of grpc.beta._connectivity_channel."""
+
+import threading
+import time
+import unittest
+
+from grpc._adapter import _low
+from grpc._adapter import _types
+from grpc.beta import _connectivity_channel
+from grpc.beta import interfaces
+from tests.unit.framework.common import test_constants
+
+
+def _drive_completion_queue(completion_queue):
+  while True:
+    event = completion_queue.next(time.time() + 24 * 60 * 60)
+    if event.type == _types.EventType.QUEUE_SHUTDOWN:
+      break
+
+
+class _Callback(object):
+
+  def __init__(self):
+    self._condition = threading.Condition()
+    self._connectivities = []
+
+  def update(self, connectivity):
+    with self._condition:
+      self._connectivities.append(connectivity)
+      self._condition.notify()
+
+  def connectivities(self):
+    with self._condition:
+      return tuple(self._connectivities)
+
+  def block_until_connectivities_satisfy(self, predicate):
+    with self._condition:
+      while True:
+        connectivities = tuple(self._connectivities)
+        if predicate(connectivities):
+          return connectivities
+        else:
+          self._condition.wait()
+
+
+class ChannelConnectivityTest(unittest.TestCase):
+
+  def test_lonely_channel_connectivity(self):
+    low_channel = _low.Channel('localhost:12345', ())
+    callback = _Callback()
+
+    connectivity_channel = _connectivity_channel.ConnectivityChannel(
+        low_channel)
+    connectivity_channel.subscribe(callback.update, try_to_connect=False)
+    first_connectivities = callback.block_until_connectivities_satisfy(bool)
+    connectivity_channel.subscribe(callback.update, try_to_connect=True)
+    second_connectivities = callback.block_until_connectivities_satisfy(
+        lambda connectivities: 2 <= len(connectivities))
+    # Wait for a connection that will never happen.
+    time.sleep(test_constants.SHORT_TIMEOUT)
+    third_connectivities = callback.connectivities()
+    connectivity_channel.unsubscribe(callback.update)
+    fourth_connectivities = callback.connectivities()
+    connectivity_channel.unsubscribe(callback.update)
+    fifth_connectivities = callback.connectivities()
+
+    self.assertSequenceEqual(
+        (interfaces.ChannelConnectivity.IDLE,), first_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.READY, second_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.READY, third_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.READY, fourth_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.READY, fifth_connectivities)
+
+  def test_immediately_connectable_channel_connectivity(self):
+    server_completion_queue = _low.CompletionQueue()
+    server = _low.Server(server_completion_queue, [])
+    port = server.add_http2_port('[::]:0')
+    server.start()
+    server_completion_queue_thread = threading.Thread(
+        target=_drive_completion_queue, args=(server_completion_queue,))
+    server_completion_queue_thread.start()
+    low_channel = _low.Channel('localhost:%d' % port, ())
+    first_callback = _Callback()
+    second_callback = _Callback()
+
+    connectivity_channel = _connectivity_channel.ConnectivityChannel(
+        low_channel)
+    connectivity_channel.subscribe(first_callback.update, try_to_connect=False)
+    first_connectivities = first_callback.block_until_connectivities_satisfy(
+        bool)
+    # Wait for a connection that will never happen because try_to_connect=True
+    # has not yet been passed.
+    time.sleep(test_constants.SHORT_TIMEOUT)
+    second_connectivities = first_callback.connectivities()
+    connectivity_channel.subscribe(second_callback.update, try_to_connect=True)
+    third_connectivities = first_callback.block_until_connectivities_satisfy(
+        lambda connectivities: 2 <= len(connectivities))
+    fourth_connectivities = second_callback.block_until_connectivities_satisfy(
+        bool)
+    # Wait for a connection that will happen (or may already have happened).
+    first_callback.block_until_connectivities_satisfy(
+        lambda connectivities:
+        interfaces.ChannelConnectivity.READY in connectivities)
+    second_callback.block_until_connectivities_satisfy(
+        lambda connectivities:
+        interfaces.ChannelConnectivity.READY in connectivities)
+    connectivity_channel.unsubscribe(first_callback.update)
+    connectivity_channel.unsubscribe(second_callback.update)
+
+    server.shutdown()
+    server_completion_queue.shutdown()
+    server_completion_queue_thread.join()
+
+    self.assertSequenceEqual(
+        (interfaces.ChannelConnectivity.IDLE,), first_connectivities)
+    self.assertSequenceEqual(
+        (interfaces.ChannelConnectivity.IDLE,), second_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.TRANSIENT_FAILURE, third_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.FATAL_FAILURE, third_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.TRANSIENT_FAILURE,
+        fourth_connectivities)
+    self.assertNotIn(
+        interfaces.ChannelConnectivity.FATAL_FAILURE, fourth_connectivities)
+
+  def test_reachable_then_unreachable_channel_connectivity(self):
+    server_completion_queue = _low.CompletionQueue()
+    server = _low.Server(server_completion_queue, [])
+    port = server.add_http2_port('[::]:0')
+    server.start()
+    server_completion_queue_thread = threading.Thread(
+        target=_drive_completion_queue, args=(server_completion_queue,))
+    server_completion_queue_thread.start()
+    low_channel = _low.Channel('localhost:%d' % port, ())
+    callback = _Callback()
+
+    connectivity_channel = _connectivity_channel.ConnectivityChannel(
+        low_channel)
+    connectivity_channel.subscribe(callback.update, try_to_connect=True)
+    callback.block_until_connectivities_satisfy(
+        lambda connectivities:
+        interfaces.ChannelConnectivity.READY in connectivities)
+    # Now take down the server and confirm that channel readiness is repudiated.
+    server.shutdown()
+    callback.block_until_connectivities_satisfy(
+        lambda connectivities:
+        connectivities[-1] is not interfaces.ChannelConnectivity.READY)
+    connectivity_channel.unsubscribe(callback.update)
+
+    server.shutdown()
+    server_completion_queue.shutdown()
+    server_completion_queue_thread.join()
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)