Merge branch 'master' into epoll_changes

10 files changed, 1476 insertions, 29 deletions

diff --git a/src/python/grpcio/tests/interop/client.py b/src/python/grpcio/tests/interop/client.py
index db29eb4aa7..e3d5545a02 100644
--- a/src/python/grpcio/tests/interop/client.py
+++ b/src/python/grpcio/tests/interop/client.py
@@ -65,39 +65,34 @@ def _args():
       help='email address of the default service account', type=str)
   return parser.parse_args()
 
-def _oauth_access_token(args):
-  credentials = oauth2client_client.GoogleCredentials.get_application_default()
-  scoped_credentials = credentials.create_scoped([args.oauth_scope])
-  return scoped_credentials.get_access_token().access_token
 
 def _stub(args):
-  if args.oauth_scope:
-    if args.test_case == 'oauth2_auth_token':
-      # TODO(jtattermusch): This testcase sets the auth metadata key-value
-      # manually, which also means that the user would need to do the same
-      # thing every time he/she would like to use and out of band oauth token.
-      # The transformer function that produces the metadata key-value from
-      # the access token should be provided by gRPC auth library.
-      access_token = _oauth_access_token(args)
-      metadata_transformer = lambda x: [
-          ('authorization', 'Bearer %s' % access_token)]
-    else:
-      metadata_transformer = lambda x: [
-          ('authorization', 'Bearer %s' % _oauth_access_token(args))]
+  if args.test_case == 'oauth2_auth_token':
+    creds = oauth2client_client.GoogleCredentials.get_application_default()
+    scoped_creds = creds.create_scoped([args.oauth_scope])
+    access_token = scoped_creds.get_access_token().access_token
+    call_creds = implementations.access_token_call_credentials(access_token)
+  elif args.test_case == 'compute_engine_creds':
+    creds = oauth2client_client.GoogleCredentials.get_application_default()
+    scoped_creds = creds.create_scoped([args.oauth_scope])
+    call_creds = implementations.google_call_credentials(scoped_creds)
   else:
-    metadata_transformer = lambda x: []
+    call_creds = None
   if args.use_tls:
     if args.use_test_ca:
       root_certificates = resources.test_root_certificates()
     else:
       root_certificates = None  # will load default roots.
 
+    channel_creds = implementations.ssl_channel_credentials(root_certificates)
+    if call_creds is not None:
+      channel_creds = implementations.composite_channel_credentials(
+          channel_creds, call_creds)
+
     channel = test_utilities.not_really_secure_channel(
-        args.server_host, args.server_port,
-        implementations.ssl_channel_credentials(root_certificates),
+        args.server_host, args.server_port, channel_creds,
         args.server_host_override)
-    stub = test_pb2.beta_create_TestService_stub(
-        channel, metadata_transformer=metadata_transformer)
+    stub = test_pb2.beta_create_TestService_stub(channel)
   else:
     channel = implementations.insecure_channel(
         args.server_host, args.server_port)
diff --git a/src/python/grpcio/tests/interop/methods.py b/src/python/grpcio/tests/interop/methods.py
index 67862ed7d3..d5ef0c68bb 100644
--- a/src/python/grpcio/tests/interop/methods.py
+++ b/src/python/grpcio/tests/interop/methods.py
@@ -39,6 +39,8 @@ import time
 
 from oauth2client import client as oauth2client_client
 
+from grpc.beta import implementations
+from grpc.beta import interfaces
 from grpc.framework.common import cardinality
 from grpc.framework.interfaces.face import face
 
@@ -88,13 +90,15 @@ class TestService(test_pb2.BetaTestServiceServicer):
     return self.FullDuplexCall(request_iterator, context)
 
 
-def _large_unary_common_behavior(stub, fill_username, fill_oauth_scope):
+def _large_unary_common_behavior(stub, fill_username, fill_oauth_scope,
+                                 protocol_options=None):
   with stub:
     request = messages_pb2.SimpleRequest(
         response_type=messages_pb2.COMPRESSABLE, response_size=314159,
         payload=messages_pb2.Payload(body=b'\x00' * 271828),
         fill_username=fill_username, fill_oauth_scope=fill_oauth_scope)
-    response_future = stub.UnaryCall.future(request, _TIMEOUT)
+    response_future = stub.UnaryCall.future(request, _TIMEOUT,
+                                            protocol_options=protocol_options)
     response = response_future.result()
     if response.payload.type is not messages_pb2.COMPRESSABLE:
       raise ValueError(
@@ -303,7 +307,24 @@ def _oauth2_auth_token(stub, args):
   if args.oauth_scope.find(response.oauth_scope) == -1:
     raise ValueError(
         'expected to find oauth scope "%s" in received "%s"' %
-            (response.oauth_scope, args.oauth_scope))
+        (response.oauth_scope, args.oauth_scope))
+
+
+def _per_rpc_creds(stub, args):
+  json_key_filename = os.environ[
+      oauth2client_client.GOOGLE_APPLICATION_CREDENTIALS]
+  wanted_email = json.load(open(json_key_filename, 'rb'))['client_email']
+  credentials = oauth2client_client.GoogleCredentials.get_application_default()
+  scoped_credentials = credentials.create_scoped([args.oauth_scope])
+  call_creds = implementations.google_call_credentials(scoped_credentials)
+  options = interfaces.grpc_call_options(disable_compression=False,
+                                         credentials=call_creds)
+  response = _large_unary_common_behavior(stub, True, False,
+                                          protocol_options=options)
+  if wanted_email != response.username:
+    raise ValueError(
+        'expected username %s, got %s' % (wanted_email, response.username))
+
 
 @enum.unique
 class TestCase(enum.Enum):
@@ -317,6 +338,7 @@ class TestCase(enum.Enum):
   EMPTY_STREAM = 'empty_stream'
   COMPUTE_ENGINE_CREDS = 'compute_engine_creds'
   OAUTH2_AUTH_TOKEN = 'oauth2_auth_token'
+  PER_RPC_CREDS = 'per_rpc_creds'
   TIMEOUT_ON_SLEEPING_SERVER = 'timeout_on_sleeping_server'
 
   def test_interoperability(self, stub, args):
@@ -342,5 +364,7 @@ class TestCase(enum.Enum):
       _compute_engine_creds(stub, args)
     elif self is TestCase.OAUTH2_AUTH_TOKEN:
       _oauth2_auth_token(stub, args)
+    elif self is TestCase.PER_RPC_CREDS:
+      _per_rpc_creds(stub, args)
     else:
       raise NotImplementedError('Test case "%s" not implemented!' % self.name)
diff --git a/src/python/grpcio/tests/tests.json b/src/python/grpcio/tests/tests.json
index 1beb619f87..8dc47bf69d 100644
--- a/src/python/grpcio/tests/tests.json
+++ b/src/python/grpcio/tests/tests.json
@@ -1,4 +1,6 @@
 [
+  "_auth_test.AccessTokenCallCredentialsTest",
+  "_auth_test.GoogleCallCredentialsTest",
   "_base_interface_test.AsyncEasyTest", 
   "_base_interface_test.AsyncPeasyTest", 
   "_base_interface_test.SyncEasyTest", 
@@ -6,6 +8,8 @@
   "_beta_features_test.BetaFeaturesTest", 
   "_beta_features_test.ContextManagementAndLifecycleTest", 
   "_cancel_many_calls_test.CancelManyCallsTest",
+  "_channel_connectivity_test.ChannelConnectivityTest",
+  "_channel_ready_future_test.ChannelReadyFutureTest",
   "_channel_test.ChannelTest", 
   "_connectivity_channel_test.ChannelConnectivityTest", 
   "_core_over_links_base_interface_test.AsyncEasyTest", 
@@ -31,6 +35,7 @@
   "_face_interface_test.MultiCallableInvokerBlockingInvocationInlineServiceTest", 
   "_face_interface_test.MultiCallableInvokerFutureInvocationAsynchronousEventServiceTest",
   "_health_servicer_test.HealthServicerTest",
+  "_implementations_test.CallCredentialsTest",
   "_implementations_test.ChannelCredentialsTest", 
   "_insecure_interop_test.InsecureInteropTest", 
   "_intermediary_low_test.CancellationTest", 
@@ -43,6 +48,8 @@
   "_low_test.HangingServerShutdown", 
   "_low_test.InsecureServerInsecureClient", 
   "_not_found_test.NotFoundTest", 
+  "_read_some_but_not_all_responses_test.ReadSomeButNotAllResponsesTest",
+  "_rpc_test.RPCTest",
   "_sanity_test.Sanity", 
   "_secure_interop_test.SecureInteropTest", 
   "_transmission_test.RoundTripTest", 
diff --git a/src/python/grpcio/tests/unit/_channel_connectivity_test.py b/src/python/grpcio/tests/unit/_channel_connectivity_test.py
new file mode 100644
index 0000000000..a1575efada
--- /dev/null
+++ b/src/python/grpcio/tests/unit/_channel_connectivity_test.py
@@ -0,0 +1,161 @@
+# 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._channel.Channel connectivity."""
+
+import threading
+import time
+import unittest
+from concurrent import futures
+
+import grpc
+from grpc import _channel
+from grpc import _server
+from tests.unit.framework.common import test_constants
+
+
+def _ready_in_connectivities(connectivities):
+  return grpc.ChannelConnectivity.READY in connectivities
+
+
+def _last_connectivity_is_not_ready(connectivities):
+  return connectivities[-1] is not grpc.ChannelConnectivity.READY
+
+
+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):
+    callback = _Callback()
+
+    channel = _channel.Channel('localhost:12345', None, None)
+    channel.subscribe(callback.update, try_to_connect=False)
+    first_connectivities = callback.block_until_connectivities_satisfy(bool)
+    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()
+    channel.unsubscribe(callback.update)
+    fourth_connectivities = callback.connectivities()
+    channel.unsubscribe(callback.update)
+    fifth_connectivities = callback.connectivities()
+
+    self.assertSequenceEqual(
+        (grpc.ChannelConnectivity.IDLE,), first_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.READY, second_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.READY, third_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.READY, fourth_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.READY, fifth_connectivities)
+
+  def test_immediately_connectable_channel_connectivity(self):
+    server = _server.Server((), futures.ThreadPoolExecutor(max_workers=0))
+    port = server.add_insecure_port('[::]:0')
+    server.start()
+    first_callback = _Callback()
+    second_callback = _Callback()
+
+    channel = _channel.Channel('localhost:{}'.format(port), None, None)
+    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()
+    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(_ready_in_connectivities)
+    second_callback.block_until_connectivities_satisfy(_ready_in_connectivities)
+    del channel
+
+    self.assertSequenceEqual(
+        (grpc.ChannelConnectivity.IDLE,), first_connectivities)
+    self.assertSequenceEqual(
+        (grpc.ChannelConnectivity.IDLE,), second_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.TRANSIENT_FAILURE, third_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.FATAL_FAILURE, third_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.TRANSIENT_FAILURE,
+        fourth_connectivities)
+    self.assertNotIn(
+        grpc.ChannelConnectivity.FATAL_FAILURE, fourth_connectivities)
+
+  def test_reachable_then_unreachable_channel_connectivity(self):
+    server = _server.Server((), futures.ThreadPoolExecutor(max_workers=0))
+    port = server.add_insecure_port('[::]:0')
+    server.start()
+    callback = _Callback()
+
+    channel = _channel.Channel('localhost:{}'.format(port), None, None)
+    channel.subscribe(callback.update, try_to_connect=True)
+    callback.block_until_connectivities_satisfy(_ready_in_connectivities)
+    # Now take down the server and confirm that channel readiness is repudiated.
+    server.stop(None)
+    callback.block_until_connectivities_satisfy(_last_connectivity_is_not_ready)
+    channel.unsubscribe(callback.update)
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)
diff --git a/src/python/grpcio/tests/unit/_channel_ready_future_test.py b/src/python/grpcio/tests/unit/_channel_ready_future_test.py
new file mode 100644
index 0000000000..b84bc0197a
--- /dev/null
+++ b/src/python/grpcio/tests/unit/_channel_ready_future_test.py
@@ -0,0 +1,103 @@
+# 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.channel_ready_future."""
+
+import threading
+import unittest
+from concurrent import futures
+
+import grpc
+from grpc import _channel
+from grpc import _server
+from tests.unit.framework.common import test_constants
+
+
+class _Callback(object):
+
+  def __init__(self):
+    self._condition = threading.Condition()
+    self._value = None
+
+  def accept_value(self, value):
+    with self._condition:
+      self._value = value
+      self._condition.notify_all()
+
+  def block_until_called(self):
+    with self._condition:
+      while self._value is None:
+        self._condition.wait()
+      return self._value
+
+
+class ChannelReadyFutureTest(unittest.TestCase):
+
+  def test_lonely_channel_connectivity(self):
+    channel = grpc.insecure_channel('localhost:12345')
+    callback = _Callback()
+
+    ready_future = grpc.channel_ready_future(channel)
+    ready_future.add_done_callback(callback.accept_value)
+    with self.assertRaises(grpc.FutureTimeoutError):
+      ready_future.result(test_constants.SHORT_TIMEOUT)
+    self.assertFalse(ready_future.cancelled())
+    self.assertFalse(ready_future.done())
+    self.assertTrue(ready_future.running())
+    ready_future.cancel()
+    value_passed_to_callback = callback.block_until_called()
+    self.assertIs(ready_future, value_passed_to_callback)
+    self.assertTrue(ready_future.cancelled())
+    self.assertTrue(ready_future.done())
+    self.assertFalse(ready_future.running())
+
+  def test_immediately_connectable_channel_connectivity(self):
+    server = _server.Server((), futures.ThreadPoolExecutor(max_workers=0))
+    port = server.add_insecure_port('[::]:0')
+    server.start()
+    channel = grpc.insecure_channel('localhost:{}'.format(port))
+    callback = _Callback()
+
+    ready_future = grpc.channel_ready_future(channel)
+    ready_future.add_done_callback(callback.accept_value)
+    self.assertIsNone(ready_future.result(test_constants.SHORT_TIMEOUT))
+    value_passed_to_callback = callback.block_until_called()
+    self.assertIs(ready_future, value_passed_to_callback)
+    self.assertFalse(ready_future.cancelled())
+    self.assertTrue(ready_future.done())
+    self.assertFalse(ready_future.running())
+    # Cancellation after maturity has no effect.
+    ready_future.cancel()
+    self.assertFalse(ready_future.cancelled())
+    self.assertTrue(ready_future.done())
+    self.assertFalse(ready_future.running())
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)
diff --git a/src/python/grpcio/tests/unit/_cython/_read_some_but_not_all_responses_test.py b/src/python/grpcio/tests/unit/_cython/_read_some_but_not_all_responses_test.py
new file mode 100644
index 0000000000..6ae7a90fbe
--- /dev/null
+++ b/src/python/grpcio/tests/unit/_cython/_read_some_but_not_all_responses_test.py
@@ -0,0 +1,251 @@
+# Copyright 2016, 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.
+
+"""Test a corner-case at the level of the Cython API."""
+
+import threading
+import unittest
+
+from grpc._cython import cygrpc
+
+_INFINITE_FUTURE = cygrpc.Timespec(float('+inf'))
+_EMPTY_FLAGS = 0
+_EMPTY_METADATA = cygrpc.Metadata(())
+
+
+class _ServerDriver(object):
+
+  def __init__(self, completion_queue, shutdown_tag):
+    self._condition = threading.Condition()
+    self._completion_queue = completion_queue
+    self._shutdown_tag = shutdown_tag
+    self._events = []
+    self._saw_shutdown_tag = False
+
+  def start(self):
+    def in_thread():
+      while True:
+        event = self._completion_queue.poll()
+        with self._condition:
+          self._events.append(event)
+          self._condition.notify()
+          if event.tag is self._shutdown_tag:
+            self._saw_shutdown_tag = True
+            break
+    thread = threading.Thread(target=in_thread)
+    thread.start()
+
+  def done(self):
+    with self._condition:
+      return self._saw_shutdown_tag
+
+  def first_event(self):
+    with self._condition:
+      while not self._events:
+        self._condition.wait()
+      return self._events[0]
+
+  def events(self):
+    with self._condition:
+      while not self._saw_shutdown_tag:
+        self._condition.wait()
+      return tuple(self._events)
+
+
+class _QueueDriver(object):
+
+  def __init__(self, condition, completion_queue, due):
+    self._condition = condition
+    self._completion_queue = completion_queue
+    self._due = due
+    self._events = []
+    self._returned = False
+
+  def start(self):
+    def in_thread():
+      while True:
+        event = self._completion_queue.poll()
+        with self._condition:
+          self._events.append(event)
+          self._due.remove(event.tag)
+          self._condition.notify_all()
+          if not self._due:
+            self._returned = True
+            return
+    thread = threading.Thread(target=in_thread)
+    thread.start()
+
+  def done(self):
+    with self._condition:
+      return self._returned
+
+  def event_with_tag(self, tag):
+    with self._condition:
+      while True:
+        for event in self._events:
+          if event.tag is tag:
+            return event
+        self._condition.wait()
+
+  def events(self):
+    with self._condition:
+      while not self._returned:
+        self._condition.wait()
+      return tuple(self._events)
+
+
+class ReadSomeButNotAllResponsesTest(unittest.TestCase):
+
+  def testReadSomeButNotAllResponses(self):
+    server_completion_queue = cygrpc.CompletionQueue()
+    server = cygrpc.Server()
+    server.register_completion_queue(server_completion_queue)
+    port = server.add_http2_port('[::]:0')
+    server.start()
+    channel = cygrpc.Channel('localhost:{}'.format(port))
+
+    server_shutdown_tag = 'server_shutdown_tag'
+    server_driver = _ServerDriver(server_completion_queue, server_shutdown_tag)
+    server_driver.start()
+
+    client_condition = threading.Condition()
+    client_due = set()
+    client_completion_queue = cygrpc.CompletionQueue()
+    client_driver = _QueueDriver(
+        client_condition, client_completion_queue, client_due)
+    client_driver.start()
+
+    server_call_condition = threading.Condition()
+    server_send_initial_metadata_tag = 'server_send_initial_metadata_tag'
+    server_send_first_message_tag = 'server_send_first_message_tag'
+    server_send_second_message_tag = 'server_send_second_message_tag'
+    server_complete_rpc_tag = 'server_complete_rpc_tag'
+    server_call_due = set((
+        server_send_initial_metadata_tag,
+        server_send_first_message_tag,
+        server_send_second_message_tag,
+        server_complete_rpc_tag,
+    ))
+    server_call_completion_queue = cygrpc.CompletionQueue()
+    server_call_driver = _QueueDriver(
+        server_call_condition, server_call_completion_queue, server_call_due)
+    server_call_driver.start()
+
+    server_rpc_tag = 'server_rpc_tag'
+    request_call_result = server.request_call(
+        server_call_completion_queue, server_completion_queue, server_rpc_tag)
+
+    client_call = channel.create_call(
+        None, _EMPTY_FLAGS, client_completion_queue, b'/twinkies', None,
+        _INFINITE_FUTURE)
+    client_receive_initial_metadata_tag = 'client_receive_initial_metadata_tag'
+    client_complete_rpc_tag = 'client_complete_rpc_tag'
+    with client_condition:
+      client_receive_initial_metadata_start_batch_result = (
+          client_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),
+          ]), client_receive_initial_metadata_tag))
+      client_due.add(client_receive_initial_metadata_tag)
+      client_complete_rpc_start_batch_result = (
+          client_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_send_initial_metadata(
+                  _EMPTY_METADATA, _EMPTY_FLAGS),
+              cygrpc.operation_send_close_from_client(_EMPTY_FLAGS),
+              cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS),
+          ]), client_complete_rpc_tag))
+      client_due.add(client_complete_rpc_tag)
+
+    server_rpc_event = server_driver.first_event()
+
+    with server_call_condition:
+      server_send_initial_metadata_start_batch_result = (
+          server_rpc_event.operation_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_send_initial_metadata(
+                  _EMPTY_METADATA, _EMPTY_FLAGS),
+          ]), server_send_initial_metadata_tag))
+      server_send_first_message_start_batch_result = (
+          server_rpc_event.operation_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_send_message(b'\x07', _EMPTY_FLAGS),
+          ]), server_send_first_message_tag))
+    server_send_initial_metadata_event = server_call_driver.event_with_tag(
+        server_send_initial_metadata_tag)
+    server_send_first_message_event = server_call_driver.event_with_tag(
+        server_send_first_message_tag)
+    with server_call_condition:
+      server_send_second_message_start_batch_result = (
+          server_rpc_event.operation_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_send_message(b'\x07', _EMPTY_FLAGS),
+          ]), server_send_second_message_tag))
+      server_complete_rpc_start_batch_result = (
+          server_rpc_event.operation_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_receive_close_on_server(_EMPTY_FLAGS),
+              cygrpc.operation_send_status_from_server(
+                  cygrpc.Metadata(()), cygrpc.StatusCode.ok, b'test details',
+                  _EMPTY_FLAGS),
+          ]), server_complete_rpc_tag))
+    server_send_second_message_event = server_call_driver.event_with_tag(
+        server_send_second_message_tag)
+    server_complete_rpc_event = server_call_driver.event_with_tag(
+        server_complete_rpc_tag)
+    server_call_driver.events()
+
+    with client_condition:
+      client_receive_first_message_tag = 'client_receive_first_message_tag'
+      client_receive_first_message_start_batch_result = (
+          client_call.start_batch(cygrpc.Operations([
+              cygrpc.operation_receive_message(_EMPTY_FLAGS),
+          ]), client_receive_first_message_tag))
+      client_due.add(client_receive_first_message_tag)
+    client_receive_first_message_event = client_driver.event_with_tag(
+        client_receive_first_message_tag)
+
+    client_call_cancel_result = client_call.cancel()
+    client_driver.events()
+
+    server.shutdown(server_completion_queue, server_shutdown_tag)
+    server.cancel_all_calls()
+    server_driver.events()
+
+    self.assertEqual(cygrpc.CallError.ok, request_call_result)
+    self.assertEqual(
+        cygrpc.CallError.ok, server_send_initial_metadata_start_batch_result)
+    self.assertEqual(
+        cygrpc.CallError.ok, client_receive_initial_metadata_start_batch_result)
+    self.assertEqual(
+        cygrpc.CallError.ok, client_complete_rpc_start_batch_result)
+    self.assertEqual(cygrpc.CallError.ok, client_call_cancel_result)
+    self.assertIs(server_rpc_tag, server_rpc_event.tag)
+    self.assertEqual(
+        cygrpc.CompletionType.operation_complete, server_rpc_event.type)
+    self.assertIsInstance(server_rpc_event.operation_call, cygrpc.Call)
+    self.assertEqual(0, len(server_rpc_event.batch_operations))
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)
diff --git a/src/python/grpcio/tests/unit/_rpc_test.py b/src/python/grpcio/tests/unit/_rpc_test.py
new file mode 100644
index 0000000000..1c7a14c5d0
--- /dev/null
+++ b/src/python/grpcio/tests/unit/_rpc_test.py
@@ -0,0 +1,775 @@
+# Copyright 2016, 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.
+
+"""Test of gRPC Python's application-layer API."""
+
+import itertools
+import threading
+import unittest
+from concurrent import futures
+
+import grpc
+from grpc.framework.foundation import logging_pool
+
+from tests.unit.framework.common import test_constants
+from tests.unit.framework.common import test_control
+
+_SERIALIZE_REQUEST = lambda bytestring: bytestring * 2
+_DESERIALIZE_REQUEST = lambda bytestring: bytestring[len(bytestring) / 2:]
+_SERIALIZE_RESPONSE = lambda bytestring: bytestring * 3
+_DESERIALIZE_RESPONSE = lambda bytestring: bytestring[:len(bytestring) / 3]
+
+_UNARY_UNARY = b'/test/UnaryUnary'
+_UNARY_STREAM = b'/test/UnaryStream'
+_STREAM_UNARY = b'/test/StreamUnary'
+_STREAM_STREAM = b'/test/StreamStream'
+
+
+class _Callback(object):
+
+  def __init__(self):
+    self._condition = threading.Condition()
+    self._value = None
+    self._called = False
+
+  def __call__(self, value):
+    with self._condition:
+      self._value = value
+      self._called = True
+      self._condition.notify_all()
+
+  def value(self):
+    with self._condition:
+      while not self._called:
+        self._condition.wait()
+      return self._value
+
+
+class _Handler(object):
+
+  def __init__(self, control):
+    self._control = control
+
+  def handle_unary_unary(self, request, servicer_context):
+    self._control.control()
+    if servicer_context is not None:
+      servicer_context.set_trailing_metadata(((b'testkey', b'testvalue',),))
+    return request
+
+  def handle_unary_stream(self, request, servicer_context):
+    for _ in range(test_constants.STREAM_LENGTH):
+      self._control.control()
+      yield request
+    self._control.control()
+    if servicer_context is not None:
+      servicer_context.set_trailing_metadata(((b'testkey', b'testvalue',),))
+
+  def handle_stream_unary(self, request_iterator, servicer_context):
+    if servicer_context is not None:
+      servicer_context.invocation_metadata()
+    self._control.control()
+    response_elements = []
+    for request in request_iterator:
+      self._control.control()
+      response_elements.append(request)
+    self._control.control()
+    if servicer_context is not None:
+      servicer_context.set_trailing_metadata(((b'testkey', b'testvalue',),))
+    return b''.join(response_elements)
+
+  def handle_stream_stream(self, request_iterator, servicer_context):
+    self._control.control()
+    if servicer_context is not None:
+      servicer_context.set_trailing_metadata(((b'testkey', b'testvalue',),))
+    for request in request_iterator:
+      self._control.control()
+      yield request
+    self._control.control()
+
+
+class _MethodHandler(grpc.RpcMethodHandler):
+
+  def __init__(
+      self, request_streaming, response_streaming, request_deserializer,
+      response_serializer, unary_unary, unary_stream, stream_unary,
+      stream_stream):
+    self.request_streaming = request_streaming
+    self.response_streaming = response_streaming
+    self.request_deserializer = request_deserializer
+    self.response_serializer = response_serializer
+    self.unary_unary = unary_unary
+    self.unary_stream = unary_stream
+    self.stream_unary = stream_unary
+    self.stream_stream = stream_stream
+
+
+class _GenericHandler(grpc.GenericRpcHandler):
+
+  def __init__(self, handler):
+    self._handler = handler
+
+  def service(self, handler_call_details):
+    if handler_call_details.method == _UNARY_UNARY:
+      return _MethodHandler(
+          False, False, None, None, self._handler.handle_unary_unary, None,
+          None, None)
+    elif handler_call_details.method == _UNARY_STREAM:
+      return _MethodHandler(
+        False, True, _DESERIALIZE_REQUEST, _SERIALIZE_RESPONSE, None,
+        self._handler.handle_unary_stream, None, None)
+    elif handler_call_details.method == _STREAM_UNARY:
+      return _MethodHandler(
+          True, False, _DESERIALIZE_REQUEST, _SERIALIZE_RESPONSE, None, None,
+          self._handler.handle_stream_unary, None)
+    elif handler_call_details.method == _STREAM_STREAM:
+      return _MethodHandler(
+          True, True, None, None, None, None, None,
+          self._handler.handle_stream_stream)
+    else:
+      return None
+
+
+def _unary_unary_multi_callable(channel):
+  return channel.unary_unary(_UNARY_UNARY)
+
+
+def _unary_stream_multi_callable(channel):
+  return channel.unary_stream(
+      _UNARY_STREAM,
+      request_serializer=_SERIALIZE_REQUEST,
+      response_deserializer=_DESERIALIZE_RESPONSE)
+
+
+def _stream_unary_multi_callable(channel):
+  return channel.stream_unary(
+      _STREAM_UNARY,
+      request_serializer=_SERIALIZE_REQUEST,
+      response_deserializer=_DESERIALIZE_RESPONSE)
+
+
+def _stream_stream_multi_callable(channel):
+  return channel.stream_stream(_STREAM_STREAM)
+
+
+class RPCTest(unittest.TestCase):
+
+  def setUp(self):
+    self._control = test_control.PauseFailControl()
+    self._handler = _Handler(self._control)
+    self._server_pool = logging_pool.pool(test_constants.THREAD_CONCURRENCY)
+
+    self._server = grpc.server((), self._server_pool)
+    port = self._server.add_insecure_port(b'[::]:0')
+    self._server.add_generic_rpc_handlers((_GenericHandler(self._handler),))
+    self._server.start()
+
+    self._channel = grpc.insecure_channel(b'localhost:%d' % port)
+
+  # TODO(nathaniel): Why is this necessary, and only in some development
+  # environments?
+  def tearDown(self):
+    del self._channel
+    del self._server
+    del self._server_pool
+
+  def testUnrecognizedMethod(self):
+    request = b'abc'
+
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      self._channel.unary_unary(b'NoSuchMethod')(request)
+
+    self.assertEqual(
+        grpc.StatusCode.UNIMPLEMENTED, exception_context.exception.code())
+
+  def testSuccessfulUnaryRequestBlockingUnaryResponse(self):
+    request = b'\x07\x08'
+    expected_response = self._handler.handle_unary_unary(request, None)
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    response = multi_callable(
+        request, metadata=(
+            (b'test', b'SuccessfulUnaryRequestBlockingUnaryResponse'),))
+
+    self.assertEqual(expected_response, response)
+
+  def testSuccessfulUnaryRequestBlockingUnaryResponseWithCall(self):
+    request = b'\x07\x08'
+    expected_response = self._handler.handle_unary_unary(request, None)
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    response, call = multi_callable(
+        request, metadata=(
+            (b'test', b'SuccessfulUnaryRequestBlockingUnaryResponseWithCall'),),
+        with_call=True)
+
+    self.assertEqual(expected_response, response)
+    self.assertIs(grpc.StatusCode.OK, call.code())
+
+  def testSuccessfulUnaryRequestFutureUnaryResponse(self):
+    request = b'\x07\x08'
+    expected_response = self._handler.handle_unary_unary(request, None)
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    response_future = multi_callable.future(
+        request, metadata=(
+            (b'test', b'SuccessfulUnaryRequestFutureUnaryResponse'),))
+    response = response_future.result()
+
+    self.assertEqual(expected_response, response)
+
+  def testSuccessfulUnaryRequestStreamResponse(self):
+    request = b'\x37\x58'
+    expected_responses = tuple(self._handler.handle_unary_stream(request, None))
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    response_iterator = multi_callable(
+        request,
+        metadata=((b'test', b'SuccessfulUnaryRequestStreamResponse'),))
+    responses = tuple(response_iterator)
+
+    self.assertSequenceEqual(expected_responses, responses)
+
+  def testSuccessfulStreamRequestBlockingUnaryResponse(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    expected_response = self._handler.handle_stream_unary(iter(requests), None)
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    response = multi_callable(
+        request_iterator,
+        metadata=((b'test', b'SuccessfulStreamRequestBlockingUnaryResponse'),))
+
+    self.assertEqual(expected_response, response)
+
+  def testSuccessfulStreamRequestBlockingUnaryResponseWithCall(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    expected_response = self._handler.handle_stream_unary(iter(requests), None)
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    response, call = multi_callable(
+        request_iterator,
+        metadata=(
+            (b'test', b'SuccessfulStreamRequestBlockingUnaryResponseWithCall'),
+        ), with_call=True)
+
+    self.assertEqual(expected_response, response)
+    self.assertIs(grpc.StatusCode.OK, call.code())
+
+  def testSuccessfulStreamRequestFutureUnaryResponse(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    expected_response = self._handler.handle_stream_unary(iter(requests), None)
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    response_future = multi_callable.future(
+        request_iterator,
+        metadata=(
+            (b'test', b'SuccessfulStreamRequestFutureUnaryResponse'),))
+    response = response_future.result()
+
+    self.assertEqual(expected_response, response)
+
+  def testSuccessfulStreamRequestStreamResponse(self):
+    requests = tuple(b'\x77\x58' for _ in range(test_constants.STREAM_LENGTH))
+    expected_responses = tuple(
+        self._handler.handle_stream_stream(iter(requests), None))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    response_iterator = multi_callable(
+        request_iterator,
+        metadata=((b'test', b'SuccessfulStreamRequestStreamResponse'),))
+    responses = tuple(response_iterator)
+
+    self.assertSequenceEqual(expected_responses, responses)
+
+  def testSequentialInvocations(self):
+    first_request = b'\x07\x08'
+    second_request = b'\x0809'
+    expected_first_response = self._handler.handle_unary_unary(
+        first_request, None)
+    expected_second_response = self._handler.handle_unary_unary(
+        second_request, None)
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    first_response = multi_callable(
+        first_request, metadata=((b'test', b'SequentialInvocations'),))
+    second_response = multi_callable(
+        second_request, metadata=((b'test', b'SequentialInvocations'),))
+
+    self.assertEqual(expected_first_response, first_response)
+    self.assertEqual(expected_second_response, second_response)
+
+  def testConcurrentBlockingInvocations(self):
+    pool = logging_pool.pool(test_constants.THREAD_CONCURRENCY)
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    expected_response = self._handler.handle_stream_unary(iter(requests), None)
+    expected_responses = [expected_response] * test_constants.THREAD_CONCURRENCY
+    response_futures = [None] * test_constants.THREAD_CONCURRENCY
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    for index in range(test_constants.THREAD_CONCURRENCY):
+      request_iterator = iter(requests)
+      response_future = pool.submit(
+          multi_callable, request_iterator,
+          metadata=((b'test', b'ConcurrentBlockingInvocations'),))
+      response_futures[index] = response_future
+    responses = tuple(
+        response_future.result() for response_future in response_futures)
+
+    pool.shutdown(wait=True)
+    self.assertSequenceEqual(expected_responses, responses)
+
+  def testConcurrentFutureInvocations(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    expected_response = self._handler.handle_stream_unary(iter(requests), None)
+    expected_responses = [expected_response] * test_constants.THREAD_CONCURRENCY
+    response_futures = [None] * test_constants.THREAD_CONCURRENCY
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    for index in range(test_constants.THREAD_CONCURRENCY):
+      request_iterator = iter(requests)
+      response_future = multi_callable.future(
+          request_iterator,
+          metadata=((b'test', b'ConcurrentFutureInvocations'),))
+      response_futures[index] = response_future
+    responses = tuple(
+        response_future.result() for response_future in response_futures)
+
+    self.assertSequenceEqual(expected_responses, responses)
+
+  def testWaitingForSomeButNotAllConcurrentFutureInvocations(self):
+    pool = logging_pool.pool(test_constants.THREAD_CONCURRENCY)
+    request = b'\x67\x68'
+    expected_response = self._handler.handle_unary_unary(request, None)
+    response_futures = [None] * test_constants.THREAD_CONCURRENCY
+    lock = threading.Lock()
+    test_is_running_cell = [True]
+    def wrap_future(future):
+      def wrap():
+        try:
+          return future.result()
+        except grpc.RpcError:
+          with lock:
+            if test_is_running_cell[0]:
+              raise
+          return None
+      return wrap
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    for index in range(test_constants.THREAD_CONCURRENCY):
+      inner_response_future = multi_callable.future(
+          request,
+          metadata=(
+              (b'test',
+               b'WaitingForSomeButNotAllConcurrentFutureInvocations'),))
+      outer_response_future = pool.submit(wrap_future(inner_response_future))
+      response_futures[index] = outer_response_future
+
+    some_completed_response_futures_iterator = itertools.islice(
+        futures.as_completed(response_futures),
+        test_constants.THREAD_CONCURRENCY // 2)
+    for response_future in some_completed_response_futures_iterator:
+      self.assertEqual(expected_response, response_future.result())
+    with lock:
+      test_is_running_cell[0] = False
+
+  def testConsumingOneStreamResponseUnaryRequest(self):
+    request = b'\x57\x38'
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    response_iterator = multi_callable(
+        request,
+        metadata=(
+            (b'test', b'ConsumingOneStreamResponseUnaryRequest'),))
+    next(response_iterator)
+
+  def testConsumingSomeButNotAllStreamResponsesUnaryRequest(self):
+    request = b'\x57\x38'
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    response_iterator = multi_callable(
+        request,
+        metadata=(
+            (b'test', b'ConsumingSomeButNotAllStreamResponsesUnaryRequest'),))
+    for _ in range(test_constants.STREAM_LENGTH // 2):
+      next(response_iterator)
+
+  def testConsumingSomeButNotAllStreamResponsesStreamRequest(self):
+    requests = tuple(b'\x67\x88' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    response_iterator = multi_callable(
+        request_iterator,
+        metadata=(
+            (b'test', b'ConsumingSomeButNotAllStreamResponsesStreamRequest'),))
+    for _ in range(test_constants.STREAM_LENGTH // 2):
+      next(response_iterator)
+
+  def testConsumingTooManyStreamResponsesStreamRequest(self):
+    requests = tuple(b'\x67\x88' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    response_iterator = multi_callable(
+        request_iterator,
+        metadata=(
+            (b'test', b'ConsumingTooManyStreamResponsesStreamRequest'),))
+    for _ in range(test_constants.STREAM_LENGTH):
+      next(response_iterator)
+    for _ in range(test_constants.STREAM_LENGTH):
+      with self.assertRaises(StopIteration):
+        next(response_iterator)
+
+    self.assertIsNotNone(response_iterator.initial_metadata())
+    self.assertIs(grpc.StatusCode.OK, response_iterator.code())
+    self.assertIsNotNone(response_iterator.details())
+    self.assertIsNotNone(response_iterator.trailing_metadata())
+
+  def testCancelledUnaryRequestUnaryResponse(self):
+    request = b'\x07\x17'
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    with self._control.pause():
+      response_future = multi_callable.future(
+          request,
+          metadata=((b'test', b'CancelledUnaryRequestUnaryResponse'),))
+      response_future.cancel()
+
+    self.assertTrue(response_future.cancelled())
+    with self.assertRaises(grpc.FutureCancelledError):
+      response_future.result()
+    self.assertIs(grpc.StatusCode.CANCELLED, response_future.code())
+
+  def testCancelledUnaryRequestStreamResponse(self):
+    request = b'\x07\x19'
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    with self._control.pause():
+      response_iterator = multi_callable(
+          request,
+          metadata=((b'test', b'CancelledUnaryRequestStreamResponse'),))
+      self._control.block_until_paused()
+      response_iterator.cancel()
+
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      next(response_iterator)
+    self.assertIs(grpc.StatusCode.CANCELLED, exception_context.exception.code())
+    self.assertIsNotNone(response_iterator.initial_metadata())
+    self.assertIs(grpc.StatusCode.CANCELLED, response_iterator.code())
+    self.assertIsNotNone(response_iterator.details())
+    self.assertIsNotNone(response_iterator.trailing_metadata())
+
+  def testCancelledStreamRequestUnaryResponse(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    with self._control.pause():
+      response_future = multi_callable.future(
+          request_iterator,
+          metadata=((b'test', b'CancelledStreamRequestUnaryResponse'),))
+      self._control.block_until_paused()
+      response_future.cancel()
+
+    self.assertTrue(response_future.cancelled())
+    with self.assertRaises(grpc.FutureCancelledError):
+      response_future.result()
+    self.assertIsNotNone(response_future.initial_metadata())
+    self.assertIs(grpc.StatusCode.CANCELLED, response_future.code())
+    self.assertIsNotNone(response_future.details())
+    self.assertIsNotNone(response_future.trailing_metadata())
+
+  def testCancelledStreamRequestStreamResponse(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    with self._control.pause():
+      response_iterator = multi_callable(
+          request_iterator,
+          metadata=((b'test', b'CancelledStreamRequestStreamResponse'),))
+      response_iterator.cancel()
+
+    with self.assertRaises(grpc.RpcError):
+      next(response_iterator)
+    self.assertIsNotNone(response_iterator.initial_metadata())
+    self.assertIs(grpc.StatusCode.CANCELLED, response_iterator.code())
+    self.assertIsNotNone(response_iterator.details())
+    self.assertIsNotNone(response_iterator.trailing_metadata())
+
+  def testExpiredUnaryRequestBlockingUnaryResponse(self):
+    request = b'\x07\x17'
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    with self._control.pause():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        multi_callable(
+            request, timeout=test_constants.SHORT_TIMEOUT,
+            metadata=((b'test', b'ExpiredUnaryRequestBlockingUnaryResponse'),),
+            with_call=True)
+
+    self.assertIsNotNone(exception_context.exception.initial_metadata())
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, exception_context.exception.code())
+    self.assertIsNotNone(exception_context.exception.details())
+    self.assertIsNotNone(exception_context.exception.trailing_metadata())
+
+  def testExpiredUnaryRequestFutureUnaryResponse(self):
+    request = b'\x07\x17'
+    callback = _Callback()
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    with self._control.pause():
+      response_future = multi_callable.future(
+          request, timeout=test_constants.SHORT_TIMEOUT,
+          metadata=((b'test', b'ExpiredUnaryRequestFutureUnaryResponse'),))
+      response_future.add_done_callback(callback)
+      value_passed_to_callback = callback.value()
+
+    self.assertIs(response_future, value_passed_to_callback)
+    self.assertIsNotNone(response_future.initial_metadata())
+    self.assertIs(grpc.StatusCode.DEADLINE_EXCEEDED, response_future.code())
+    self.assertIsNotNone(response_future.details())
+    self.assertIsNotNone(response_future.trailing_metadata())
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      response_future.result()
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, exception_context.exception.code())
+    self.assertIsInstance(response_future.exception(), grpc.RpcError)
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, response_future.exception().code())
+
+  def testExpiredUnaryRequestStreamResponse(self):
+    request = b'\x07\x19'
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    with self._control.pause():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        response_iterator = multi_callable(
+            request, timeout=test_constants.SHORT_TIMEOUT,
+            metadata=((b'test', b'ExpiredUnaryRequestStreamResponse'),))
+        next(response_iterator)
+
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, exception_context.exception.code())
+    self.assertIs(grpc.StatusCode.DEADLINE_EXCEEDED, response_iterator.code())
+
+  def testExpiredStreamRequestBlockingUnaryResponse(self):
+    requests = tuple(b'\x07\x08' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    with self._control.pause():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        multi_callable(
+            request_iterator, timeout=test_constants.SHORT_TIMEOUT,
+            metadata=((b'test', b'ExpiredStreamRequestBlockingUnaryResponse'),))
+
+    self.assertIsNotNone(exception_context.exception.initial_metadata())
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, exception_context.exception.code())
+    self.assertIsNotNone(exception_context.exception.details())
+    self.assertIsNotNone(exception_context.exception.trailing_metadata())
+
+  def testExpiredStreamRequestFutureUnaryResponse(self):
+    requests = tuple(b'\x07\x18' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+    callback = _Callback()
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    with self._control.pause():
+      response_future = multi_callable.future(
+          request_iterator, timeout=test_constants.SHORT_TIMEOUT,
+          metadata=((b'test', b'ExpiredStreamRequestFutureUnaryResponse'),))
+      response_future.add_done_callback(callback)
+      value_passed_to_callback = callback.value()
+
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      response_future.result()
+    self.assertIs(grpc.StatusCode.DEADLINE_EXCEEDED, response_future.code())
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, exception_context.exception.code())
+    self.assertIsInstance(response_future.exception(), grpc.RpcError)
+    self.assertIs(response_future, value_passed_to_callback)
+    self.assertIsNotNone(response_future.initial_metadata())
+    self.assertIs(grpc.StatusCode.DEADLINE_EXCEEDED, response_future.code())
+    self.assertIsNotNone(response_future.details())
+    self.assertIsNotNone(response_future.trailing_metadata())
+
+  def testExpiredStreamRequestStreamResponse(self):
+    requests = tuple(b'\x67\x18' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    with self._control.pause():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        response_iterator = multi_callable(
+            request_iterator, timeout=test_constants.SHORT_TIMEOUT,
+            metadata=((b'test', b'ExpiredStreamRequestStreamResponse'),))
+        next(response_iterator)
+
+    self.assertIs(
+        grpc.StatusCode.DEADLINE_EXCEEDED, exception_context.exception.code())
+    self.assertIs(grpc.StatusCode.DEADLINE_EXCEEDED, response_iterator.code())
+
+  def testFailedUnaryRequestBlockingUnaryResponse(self):
+    request = b'\x37\x17'
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    with self._control.fail():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        multi_callable(
+            request,
+            metadata=((b'test', b'FailedUnaryRequestBlockingUnaryResponse'),),
+            with_call=True)
+
+    self.assertIs(grpc.StatusCode.UNKNOWN, exception_context.exception.code())
+
+  def testFailedUnaryRequestFutureUnaryResponse(self):
+    request = b'\x37\x17'
+    callback = _Callback()
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    with self._control.fail():
+      response_future = multi_callable.future(
+          request,
+          metadata=((b'test', b'FailedUnaryRequestFutureUnaryResponse'),))
+      response_future.add_done_callback(callback)
+      value_passed_to_callback = callback.value()
+
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      response_future.result()
+    self.assertIs(
+        grpc.StatusCode.UNKNOWN, exception_context.exception.code())
+    self.assertIsInstance(response_future.exception(), grpc.RpcError)
+    self.assertIs(grpc.StatusCode.UNKNOWN, response_future.exception().code())
+    self.assertIs(response_future, value_passed_to_callback)
+
+  def testFailedUnaryRequestStreamResponse(self):
+    request = b'\x37\x17'
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      with self._control.fail():
+        response_iterator = multi_callable(
+            request,
+            metadata=((b'test', b'FailedUnaryRequestStreamResponse'),))
+        next(response_iterator)
+
+    self.assertIs(grpc.StatusCode.UNKNOWN, exception_context.exception.code())
+
+  def testFailedStreamRequestBlockingUnaryResponse(self):
+    requests = tuple(b'\x47\x58' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    with self._control.fail():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        multi_callable(
+            request_iterator,
+            metadata=((b'test', b'FailedStreamRequestBlockingUnaryResponse'),))
+
+    self.assertIs(grpc.StatusCode.UNKNOWN, exception_context.exception.code())
+
+  def testFailedStreamRequestFutureUnaryResponse(self):
+    requests = tuple(b'\x07\x18' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+    callback = _Callback()
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    with self._control.fail():
+      response_future = multi_callable.future(
+          request_iterator,
+          metadata=((b'test', b'FailedStreamRequestFutureUnaryResponse'),))
+      response_future.add_done_callback(callback)
+      value_passed_to_callback = callback.value()
+
+    with self.assertRaises(grpc.RpcError) as exception_context:
+      response_future.result()
+    self.assertIs(grpc.StatusCode.UNKNOWN, response_future.code())
+    self.assertIs(
+        grpc.StatusCode.UNKNOWN, exception_context.exception.code())
+    self.assertIsInstance(response_future.exception(), grpc.RpcError)
+    self.assertIs(response_future, value_passed_to_callback)
+
+  def testFailedStreamRequestStreamResponse(self):
+    requests = tuple(b'\x67\x88' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    with self._control.fail():
+      with self.assertRaises(grpc.RpcError) as exception_context:
+        response_iterator = multi_callable(
+            request_iterator,
+            metadata=((b'test', b'FailedStreamRequestStreamResponse'),))
+        tuple(response_iterator)
+
+    self.assertIs(grpc.StatusCode.UNKNOWN, exception_context.exception.code())
+    self.assertIs(grpc.StatusCode.UNKNOWN, response_iterator.code())
+
+  def testIgnoredUnaryRequestFutureUnaryResponse(self):
+    request = b'\x37\x17'
+
+    multi_callable = _unary_unary_multi_callable(self._channel)
+    multi_callable.future(
+        request,
+        metadata=((b'test', b'IgnoredUnaryRequestFutureUnaryResponse'),))
+
+  def testIgnoredUnaryRequestStreamResponse(self):
+    request = b'\x37\x17'
+
+    multi_callable = _unary_stream_multi_callable(self._channel)
+    multi_callable(
+        request,
+        metadata=((b'test', b'IgnoredUnaryRequestStreamResponse'),))
+
+  def testIgnoredStreamRequestFutureUnaryResponse(self):
+    requests = tuple(b'\x07\x18' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_unary_multi_callable(self._channel)
+    multi_callable.future(
+        request_iterator,
+        metadata=((b'test', b'IgnoredStreamRequestFutureUnaryResponse'),))
+
+  def testIgnoredStreamRequestStreamResponse(self):
+    requests = tuple(b'\x67\x88' for _ in range(test_constants.STREAM_LENGTH))
+    request_iterator = iter(requests)
+
+    multi_callable = _stream_stream_multi_callable(self._channel)
+    multi_callable(
+        request_iterator,
+        metadata=((b'test', b'IgnoredStreamRequestStreamResponse'),))
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)
diff --git a/src/python/grpcio/tests/unit/beta/_auth_test.py b/src/python/grpcio/tests/unit/beta/_auth_test.py
new file mode 100644
index 0000000000..694928a91b
--- /dev/null
+++ b/src/python/grpcio/tests/unit/beta/_auth_test.py
@@ -0,0 +1,96 @@
+# Copyright 2016, 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 standard AuthMetadataPlugins."""
+
+import collections
+import threading
+import unittest
+
+from grpc.beta import _auth
+
+
+class MockGoogleCreds(object):
+
+  def get_access_token(self):
+    token = collections.namedtuple('MockAccessTokenInfo',
+                                   ('access_token', 'expires_in'))
+    token.access_token = 'token'
+    return token
+
+
+class MockExceptionGoogleCreds(object):
+
+  def get_access_token(self):
+    raise Exception()
+
+
+class GoogleCallCredentialsTest(unittest.TestCase):
+
+  def test_google_call_credentials_success(self):
+    callback_event = threading.Event()
+
+    def mock_callback(metadata, error):
+      self.assertEqual(metadata, (('authorization', 'Bearer token'),))
+      self.assertIsNone(error)
+      callback_event.set()
+
+    call_creds = _auth.GoogleCallCredentials(MockGoogleCreds())
+    call_creds(None, mock_callback)
+    self.assertTrue(callback_event.wait(1.0))
+
+  def test_google_call_credentials_error(self):
+    callback_event = threading.Event()
+
+    def mock_callback(metadata, error):
+      self.assertIsNotNone(error)
+      callback_event.set()
+
+    call_creds = _auth.GoogleCallCredentials(MockExceptionGoogleCreds())
+    call_creds(None, mock_callback)
+    self.assertTrue(callback_event.wait(1.0))
+
+
+class AccessTokenCallCredentialsTest(unittest.TestCase):
+
+  def test_google_call_credentials_success(self):
+    callback_event = threading.Event()
+
+    def mock_callback(metadata, error):
+      self.assertEqual(metadata, (('authorization', 'Bearer token'),))
+      self.assertIsNone(error)
+      callback_event.set()
+
+    call_creds = _auth.AccessTokenCallCredentials('token')
+    call_creds(None, mock_callback)
+    self.assertTrue(callback_event.wait(1.0))
+
+
+if __name__ == '__main__':
+  unittest.main(verbosity=2)
diff --git a/src/python/grpcio/tests/unit/beta/_implementations_test.py b/src/python/grpcio/tests/unit/beta/_implementations_test.py
index 26be670c45..127f93e9bb 100644
--- a/src/python/grpcio/tests/unit/beta/_implementations_test.py
+++ b/src/python/grpcio/tests/unit/beta/_implementations_test.py
@@ -29,8 +29,11 @@
 
 """Tests the implementations module of the gRPC Python Beta API."""
 
+import datetime
 import unittest
 
+from oauth2client import client as oauth2client_client
+
 from grpc.beta import implementations
 from tests.unit import resources
 
@@ -49,5 +52,19 @@ class ChannelCredentialsTest(unittest.TestCase):
         channel_credentials, implementations.ChannelCredentials)
 
 
+class CallCredentialsTest(unittest.TestCase):
+
+  def test_google_call_credentials(self):
+    creds = oauth2client_client.GoogleCredentials(
+        'token', 'client_id', 'secret', 'refresh_token',
+        datetime.datetime(2008, 6, 24), 'https://refresh.uri.com/',
+        'user_agent')
+    call_creds = implementations.google_call_credentials(creds)
+    self.assertIsInstance(call_creds, implementations.CallCredentials)
+
+  def test_access_token_call_credentials(self):
+    call_creds = implementations.access_token_call_credentials('token')
+    self.assertIsInstance(call_creds, implementations.CallCredentials)
+
 if __name__ == '__main__':
   unittest.main(verbosity=2)
diff --git a/src/python/grpcio/tests/unit/framework/common/test_control.py b/src/python/grpcio/tests/unit/framework/common/test_control.py
index ca5ba3a854..088e2f8b88 100644
--- a/src/python/grpcio/tests/unit/framework/common/test_control.py
+++ b/src/python/grpcio/tests/unit/framework/common/test_control.py
@@ -60,10 +60,16 @@ class Control(six.with_metaclass(abc.ABCMeta)):
 
 
 class PauseFailControl(Control):
-  """A Control that can be used to pause or fail code under control."""
+  """A Control that can be used to pause or fail code under control.
+
+  This object is only safe for use from two threads: one of the system under
+  test calling control and the other from the test system calling pause,
+  block_until_paused, and fail.
+  """
 
   def __init__(self):
     self._condition = threading.Condition()
+    self._pause = False
     self._paused = False
     self._fail = False
 
@@ -72,19 +78,31 @@ class PauseFailControl(Control):
       if self._fail:
         raise Defect()
 
-      while self._paused:
+      while self._pause:
+        self._paused = True
+        self._condition.notify_all()
         self._condition.wait()
+      self._paused = False
 
   @contextlib.contextmanager
   def pause(self):
     """Pauses code under control while controlling code is in context."""
     with self._condition:
-      self._paused = True
+      self._pause = True
     yield
     with self._condition:
-      self._paused = False
+      self._pause = False
       self._condition.notify_all()
 
+  def block_until_paused(self):
+    """Blocks controlling code until code under control is paused.
+
+    May only be called within the context of a pause call.
+    """
+    with self._condition:
+      while not self._paused:
+        self._condition.wait()
+
   @contextlib.contextmanager
   def fail(self):
     """Fails code under control while controlling code is in context."""