Merge branch 'master' into rq-threads-2

.github/mergeable.yml

@@ -1,6 +1,14 @@
 mergeable:
   pull_requests:
     label:
-      must_include:
-        regex: "release notes: yes|release notes: no"
-        message: "Add release notes yes/no label. For yes, add lang label"
+      or:
+        - and:
+          - must_include:
+              regex: 'release notes: yes'
+              message: 'Please include release note: yes'
+          - must_include:
+              regex: '^lang\/'
+              message: 'Please include a language label'
+        - must_include:
+            regex: 'release notes: no'
+            message: 'Please include release note: no'

CMakeLists.txt

@@ -100,6 +100,8 @@ if (MSVC)
   add_definitions(-D_WIN32_WINNT=0x600 -D_SCL_SECURE_NO_WARNINGS -D_CRT_SECURE_NO_WARNINGS -D_WINSOCK_DEPRECATED_NO_WARNINGS)
   # needed to compile protobuf
   add_definitions(/wd4065 /wd4506)
+  # TODO(jtattermusch): revisit warnings that were silenced as part of upgrade to protobuf3.6.0
+  add_definitions(/wd4200 /wd4291 /wd4244)
   # TODO(jtattermusch): revisit C4267 occurrences throughout the code
   add_definitions(/wd4267)
   # TODO(jtattermusch): needed to build boringssl with VS2017, revisit later
@@ -660,12 +662,8 @@ add_dependencies(buildtests_cxx transport_security_common_api_test)
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx writes_per_rpc_test)
 endif()
-if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx resolver_component_test_unsecure)
-endif()
-if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx resolver_component_test)
-endif()
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx resolver_component_tests_runner_invoker_unsecure)
 endif()
@@ -674,9 +672,7 @@ add_dependencies(buildtests_cxx resolver_component_tests_runner_invoker)
 endif()
 add_dependencies(buildtests_cxx address_sorting_test_unsecure)
 add_dependencies(buildtests_cxx address_sorting_test)
-if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx cancel_ares_query_test)
-endif()
 
 add_custom_target(buildtests
   DEPENDS buildtests_c buildtests_cxx)
@@ -16211,7 +16207,6 @@ target_link_libraries(inproc_nosec_test
 
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
-if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 
 add_executable(resolver_component_test_unsecure
   test/cpp/naming/resolver_component_test.cc
@@ -16251,10 +16246,8 @@ target_link_libraries(resolver_component_test_unsecure
   ${_gRPC_GFLAGS_LIBRARIES}
 )
 
-endif()
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
-if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 
 add_executable(resolver_component_test
   test/cpp/naming/resolver_component_test.cc
@@ -16294,7 +16287,6 @@ target_link_libraries(resolver_component_test
   ${_gRPC_GFLAGS_LIBRARIES}
 )
 
-endif()
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
@@ -16465,7 +16457,6 @@ target_link_libraries(address_sorting_test
 
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
-if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 
 add_executable(cancel_ares_query_test
   test/cpp/naming/cancel_ares_query_test.cc
@@ -16505,7 +16496,6 @@ target_link_libraries(cancel_ares_query_test
   ${_gRPC_GFLAGS_LIBRARIES}
 )
 
-endif()
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
 

bazel/grpc_deps.bzl

@@ -116,9 +116,9 @@ def grpc_deps():
     if "com_google_protobuf" not in native.existing_rules():
         native.http_archive(
             name = "com_google_protobuf",
-            strip_prefix = "protobuf-b5fbb742af122b565925987e65c08957739976a7",
-            url = "https://github.com/google/protobuf/archive/b5fbb742af122b565925987e65c08957739976a7.tar.gz",
-            )
+            strip_prefix = "protobuf-48cb18e5c419ddd23d9badcfe4e9df7bde1979b2",
+            url = "https://github.com/google/protobuf/archive/48cb18e5c419ddd23d9badcfe4e9df7bde1979b2.tar.gz",
+        )
 
     if "com_github_nanopb_nanopb" not in native.existing_rules():
         native.new_http_archive(

doc/csharp/server_reflection.md

@@ -30,7 +30,8 @@ server.Start();
 ```
 
 After starting the server, you can verify that the server reflection
-is working properly by using the `grpc_cli` command line tool:
+is working properly by using the [`grpc_cli` command line
+tool](https://github.com/grpc/grpc/blob/master/doc/command_line_tool.md):
 
  ```sh
   $ grpc_cli ls localhost:50051

doc/python/server_reflection.md

@@ -0,0 +1,61 @@
+# gRPC Python Server Reflection
+
+This document shows how to use gRPC Server Reflection in gRPC Python.
+Please see [C++ Server Reflection Tutorial](../server_reflection_tutorial.md)
+for general information and more examples how to use server reflection.
+
+## Enable server reflection in Python servers
+
+gRPC Python Server Reflection is an add-on library.
+To use it, first install the [grpcio-reflection](https://pypi.org/project/grpcio-reflection/)
+PyPI package into your project.
+
+Note that with Python you need to manually register the service
+descriptors with the reflection service implementation when creating a server
+(this isn't necessary with e.g. C++ or Java)
+```python
+# add the following import statement to use server reflection
+from grpc_reflection.v1alpha import reflection
+# ...
+def serve():
+    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
+    helloworld_pb2_grpc.add_GreeterServicer_to_server(Greeter(), server)
+    # the reflection service will be aware of "Greeter" and "ServerReflection" services.
+    SERVICE_NAMES = (
+        helloworld_pb2.DESCRIPTOR.services_by_name['Greeter'].full_name,
+        reflection.SERVICE_NAME,
+    )
+    reflection.enable_server_reflection(SERVICE_NAMES, server)
+    server.add_insecure_port('[::]:50051')
+    server.start()
+```
+
+Please see
+[greeter_server_with_reflection.py](https://github.com/grpc/grpc/blob/master/examples/python/helloworld/greeter_server_with_reflection.py)
+in the examples directory for the full example, which extends the gRPC [Python
+`Greeter` example](https://github.com/grpc/tree/master/examples/python/helloworld) on a
+reflection-enabled server.
+
+After starting the server, you can verify that the server reflection
+is working properly by using the [`grpc_cli` command line
+tool](https://github.com/grpc/grpc/blob/master/doc/command_line_tool.md):
+
+ ```sh
+  $ grpc_cli ls localhost:50051
+  ```
+
+  output:
+  ```sh
+  grpc.reflection.v1alpha.ServerReflection
+  helloworld.Greeter
+  ```
+
+  For more examples and instructions how to use the `grpc_cli` tool,
+  please refer to the [`grpc_cli` documentation](../command_line_tool.md)
+  and the [C++ Server Reflection Tutorial](../server_reflection_tutorial.md).
+
+## Additional Resources
+
+The [Server Reflection Protocol](../server-reflection.md) provides detailed
+information about how the server reflection works and describes the server reflection
+protocol in detail.

examples/python/helloworld/greeter_server_with_reflection.py

@@ -0,0 +1,52 @@
+# Copyright 2018 The gRPC Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""The reflection-enabled version of gRPC helloworld.Greeter server."""
+
+from concurrent import futures
+import time
+
+import grpc
+from grpc_reflection.v1alpha import reflection
+
+import helloworld_pb2
+import helloworld_pb2_grpc
+
+_ONE_DAY_IN_SECONDS = 60 * 60 * 24
+
+
+class Greeter(helloworld_pb2_grpc.GreeterServicer):
+
+    def SayHello(self, request, context):
+        return helloworld_pb2.HelloReply(message='Hello, %s!' % request.name)
+
+
+def serve():
+    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
+    helloworld_pb2_grpc.add_GreeterServicer_to_server(Greeter(), server)
+    SERVICE_NAMES = (
+        helloworld_pb2.DESCRIPTOR.services_by_name['Greeter'].full_name,
+        reflection.SERVICE_NAME,
+    )
+    reflection.enable_server_reflection(SERVICE_NAMES, server)
+    server.add_insecure_port('[::]:50051')
+    server.start()
+    try:
+        while True:
+            time.sleep(_ONE_DAY_IN_SECONDS)
+    except KeyboardInterrupt:
+        server.stop(0)
+
+
+if __name__ == '__main__':
+    serve()

grpc.def

@@ -42,6 +42,7 @@ EXPORTS
     grpc_census_call_get_context
     grpc_channel_get_target
     grpc_channel_get_info
+    grpc_channel_reset_connect_backoff
     grpc_insecure_channel_create
     grpc_lame_client_channel_create
     grpc_channel_destroy

include/grpc/grpc.h

@@ -274,6 +274,11 @@ GRPCAPI char* grpc_channel_get_target(grpc_channel* channel);
 GRPCAPI void grpc_channel_get_info(grpc_channel* channel,
                                    const grpc_channel_info* channel_info);
 
+/** EXPERIMENTAL.  Resets the channel's connect backoff.
+    TODO(roth): When we see whether this proves useful, either promote
+    to non-experimental or remove it. */
+GRPCAPI void grpc_channel_reset_connect_backoff(grpc_channel* channel);
+
 /** Create a client channel to 'target'. Additional channel level configuration
     MAY be provided by grpc_channel_args, though the expectation is that most
     clients will want to simply pass NULL. The user data in 'args' need only

include/grpcpp/channel.h

@@ -30,6 +30,14 @@
 struct grpc_channel;
 
 namespace grpc {
+
+namespace experimental {
+/// Resets the channel's connection backoff.
+/// TODO(roth): Once we see whether this proves useful, either create a gRFC
+/// and change this to be a method of the Channel class, or remove it.
+void ChannelResetConnectionBackoff(Channel* channel);
+}  // namespace experimental
+
 /// Channels represent a connection to an endpoint. Created by \a CreateChannel.
 class Channel final : public ChannelInterface,
                       public internal::CallHook,
@@ -52,6 +60,7 @@ class Channel final : public ChannelInterface,
  private:
   template <class InputMessage, class OutputMessage>
   friend class internal::BlockingUnaryCallImpl;
+  friend void experimental::ChannelResetConnectionBackoff(Channel* channel);
   friend std::shared_ptr<Channel> CreateChannelInternal(
       const grpc::string& host, grpc_channel* c_channel);
   Channel(const grpc::string& host, grpc_channel* c_channel);

setup.py

@@ -276,11 +276,11 @@ def cython_extensions_and_necessity():
 }
 
 INSTALL_REQUIRES = (
-    "six>=1.5.2",
-    "futures>=2.2.0 ; python_version<'3.2'",
-    "enum34>=1.0.4 ; python_version<'3.4'"
+    'six>=1.5.2',
 )
 
+if not PY3:
+  INSTALL_REQUIRES += ('futures>=2.2.0', 'enum34>=1.0.4')
 
 SETUP_REQUIRES = INSTALL_REQUIRES + (
     'sphinx>=1.3',

src/core/ext/filters/client_channel/client_channel.cc

@@ -622,6 +622,17 @@ static void start_transport_op_locked(void* arg, grpc_error* error_ignored) {
     }
     GRPC_ERROR_UNREF(op->disconnect_with_error);
   }
+
+  if (op->reset_connect_backoff) {
+    if (chand->resolver != nullptr) {
+      chand->resolver->ResetBackoffLocked();
+      chand->resolver->RequestReresolutionLocked();
+    }
+    if (chand->lb_policy != nullptr) {
+      chand->lb_policy->ResetBackoffLocked();
+    }
+  }
+
   GRPC_CHANNEL_STACK_UNREF(chand->owning_stack, "start_transport_op");
 
   GRPC_CLOSURE_SCHED(op->on_consumed, GRPC_ERROR_NONE);

src/core/ext/filters/client_channel/client_channel_plugin.cc

@@ -56,7 +56,7 @@ void grpc_client_channel_init(void) {
   grpc_register_http_proxy_mapper();
   grpc_subchannel_index_init();
   grpc_channel_init_register_stage(
-      GRPC_CLIENT_CHANNEL, GRPC_CHANNEL_INIT_BUILTIN_PRIORITY, append_filter,
+      GRPC_CLIENT_CHANNEL, GRPC_CHANNEL_INIT_PRIORITY_MAX, append_filter,
       (void*)&grpc_client_channel_filter);
   grpc_http_connect_register_handshaker_factory();
 }

src/core/ext/filters/client_channel/lb_policy.h

@@ -144,7 +144,10 @@ class LoadBalancingPolicy
   /// consider whether this method is still needed.
   virtual void ExitIdleLocked() GRPC_ABSTRACT;
 
-  /// populates child_subchannels and child_channels with the uuids of this
+  /// Resets connection backoff.
+  virtual void ResetBackoffLocked() GRPC_ABSTRACT;
+
+  /// Populates child_subchannels and child_channels with the uuids of this
   /// LB policy's referenced children. This is not invoked from the
   /// client_channel's combiner. The implementation is responsible for
   /// providing its own synchronization.

src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc

@@ -134,6 +134,7 @@ class GrpcLb : public LoadBalancingPolicy {
       grpc_error** connectivity_error) override;
   void HandOffPendingPicksLocked(LoadBalancingPolicy* new_policy) override;
   void ExitIdleLocked() override;
+  void ResetBackoffLocked() override;
   void FillChildRefsForChannelz(ChildRefsList* child_subchannels,
                                 ChildRefsList* child_channels) override;
 
@@ -1214,6 +1215,15 @@ void GrpcLb::ExitIdleLocked() {
   }
 }
 
+void GrpcLb::ResetBackoffLocked() {
+  if (lb_channel_ != nullptr) {
+    grpc_channel_reset_connect_backoff(lb_channel_);
+  }
+  if (rr_policy_ != nullptr) {
+    rr_policy_->ResetBackoffLocked();
+  }
+}
+
 bool GrpcLb::PickLocked(PickState* pick, grpc_error** error) {
   PendingPick* pp = PendingPickCreate(pick);
   bool pick_done = false;
@@ -1880,7 +1890,7 @@ void grpc_lb_policy_grpclb_init() {
           grpc_core::UniquePtr<grpc_core::LoadBalancingPolicyFactory>(
               grpc_core::New<grpc_core::GrpcLbFactory>()));
   grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL,
-                                   GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,
+                                   GRPC_CHANNEL_INIT_PRIORITY_LOW,
                                    maybe_add_client_load_reporting_filter,
                                    (void*)&grpc_client_load_reporting_filter);
 }

src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc

@@ -57,6 +57,7 @@ class PickFirst : public LoadBalancingPolicy {
       grpc_error** connectivity_error) override;
   void HandOffPendingPicksLocked(LoadBalancingPolicy* new_policy) override;
   void ExitIdleLocked() override;
+  void ResetBackoffLocked() override;
   void FillChildRefsForChannelz(ChildRefsList* child_subchannels,
                                 ChildRefsList* ignored) override;
 
@@ -259,6 +260,13 @@ void PickFirst::ExitIdleLocked() {
   }
 }
 
+void PickFirst::ResetBackoffLocked() {
+  subchannel_list_->ResetBackoffLocked();
+  if (latest_pending_subchannel_list_ != nullptr) {
+    latest_pending_subchannel_list_->ResetBackoffLocked();
+  }
+}
+
 bool PickFirst::PickLocked(PickState* pick, grpc_error** error) {
   // If we have a selected subchannel already, return synchronously.
   if (selected_ != nullptr) {