| // |
| // Copyright 2016 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. |
| // |
| |
| #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H |
| #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/channel/channel_args.h" |
| #include "src/core/lib/gprpp/ref_counted.h" |
| #include "src/core/lib/iomgr/error.h" |
| |
| #define GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR \ |
| "grpc.fake_resolver.response_generator" |
| |
| namespace grpc_core { |
| |
| class FakeResolver; |
| |
| /// A mechanism for generating responses for the fake resolver. |
| /// An instance of this class is passed to the fake resolver via a channel |
| /// argument (see \a MakeChannelArg()) and used to inject and trigger custom |
| /// resolutions. |
| // TODO(roth): I would ideally like this to be InternallyRefCounted |
| // instead of RefCounted, but external refs are currently needed to |
| // encode this in channel args. Once channel_args are converted to C++, |
| // see if we can find a way to fix this. |
| class FakeResolverResponseGenerator |
| : public RefCounted<FakeResolverResponseGenerator> { |
| public: |
| FakeResolverResponseGenerator() {} |
| |
| // Instructs the fake resolver associated with the response generator |
| // instance to trigger a new resolution with the specified response. |
| void SetResponse(grpc_channel_args* next_response); |
| |
| // Sets the re-resolution response, which is returned by the fake resolver |
| // when re-resolution is requested (via \a RequestReresolutionLocked()). |
| // The new re-resolution response replaces any previous re-resolution |
| // response that may have been set by a previous call. |
| // If the re-resolution response is set to NULL, then the fake |
| // resolver will not return anything when \a RequestReresolutionLocked() |
| // is called. |
| void SetReresolutionResponse(grpc_channel_args* response); |
| |
| // Tells the resolver to return a transient failure (signalled by |
| // returning a null result with no error). |
| void SetFailure(); |
| |
| // Same as SetFailure(), but instead of returning the error |
| // immediately, waits for the next call to RequestReresolutionLocked(). |
| void SetFailureOnReresolution(); |
| |
| // Returns a channel arg containing \a generator. |
| static grpc_arg MakeChannelArg(FakeResolverResponseGenerator* generator); |
| |
| // Returns the response generator in \a args, or null if not found. |
| static FakeResolverResponseGenerator* GetFromArgs( |
| const grpc_channel_args* args); |
| |
| private: |
| friend class FakeResolver; |
| |
| static void SetResponseLocked(void* arg, grpc_error* error); |
| static void SetReresolutionResponseLocked(void* arg, grpc_error* error); |
| static void SetFailureLocked(void* arg, grpc_error* error); |
| |
| FakeResolver* resolver_ = nullptr; // Do not own. |
| }; |
| |
| } // namespace grpc_core |
| |
| #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H \ |
| */ |