1/* Copyright 2016 The TensorFlow Authors. All Rights Reserved.
2
3Licensed under the Apache License, Version 2.0 (the "License");
4you may not use this file except in compliance with the License.
5You may obtain a copy of the License at
6
7    http://www.apache.org/licenses/LICENSE-2.0
8
9Unless required by applicable law or agreed to in writing, software
10distributed under the License is distributed on an "AS IS" BASIS,
11WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12See the License for the specific language governing permissions and
13limitations under the License.
14==============================================================================*/
15
16#include "tensorflow/core/distributed_runtime/rpc/grpc_remote_master.h"
17
18#include <utility>
19
20#include "tensorflow/core/distributed_runtime/call_options.h"
21#include "tensorflow/core/distributed_runtime/master_interface.h"
22#include "tensorflow/core/distributed_runtime/rpc/grpc_master_service_impl.h"
23#include "tensorflow/core/distributed_runtime/rpc/grpc_util.h"
24#include "tensorflow/core/lib/core/errors.h"
25#include "tensorflow/core/lib/core/status.h"
26#include "tensorflow/core/lib/strings/strcat.h"
27#include "tensorflow/core/platform/tracing.h"
28#include "tensorflow/core/protobuf/master.pb.h"
29
30namespace tensorflow {
31
32// GrpcRemoteMaster is an implementation of the MasterInterface
33// that uses gRPC to talk to the Master service.
34class GrpcRemoteMaster : public MasterInterface {
35  using MasterServiceStub = grpc::MasterService::Stub;
36
37 public:
38  explicit GrpcRemoteMaster(const SharedGrpcChannelPtr& client_channel)
39      : stub_(grpc::MasterService::NewStub(client_channel)) {}
40
41  ~GrpcRemoteMaster() override {}
42
43  Status CreateSession(CallOptions* call_options,
44                       const CreateSessionRequest* request,
45                       CreateSessionResponse* response) override {
46    ::grpc::ClientContext ctx;
47    return Call(&ctx, call_options, request, response,
48                &MasterServiceStub::CreateSession);
49  }
50
51  Status ExtendSession(CallOptions* call_options,
52                       const ExtendSessionRequest* request,
53                       ExtendSessionResponse* response) override {
54    ::grpc::ClientContext ctx;
55    return Call(&ctx, call_options, request, response,
56                &MasterServiceStub::ExtendSession);
57  }
58
59  Status PartialRunSetup(CallOptions* call_options,
60                         const PartialRunSetupRequest* request,
61                         PartialRunSetupResponse* response) override {
62    ::grpc::ClientContext ctx;
63    return Call(&ctx, call_options, request, response,
64                &MasterServiceStub::PartialRunSetup);
65  }
66
67  Status RunStep(CallOptions* call_options, RunStepRequestWrapper* request,
68                 MutableRunStepResponseWrapper* response) override {
69    ::grpc::ClientContext ctx;
70    auto trace = TraceRpc("RunStep/Client", &ctx);
71    return Call(&ctx, call_options, &request->ToProto(),
72                get_proto_from_wrapper(response), &MasterServiceStub::RunStep);
73  }
74
75  Status CloseSession(CallOptions* call_options,
76                      const CloseSessionRequest* request,
77                      CloseSessionResponse* response) override {
78    ::grpc::ClientContext ctx;
79    return Call(&ctx, call_options, request, response,
80                &MasterServiceStub::CloseSession);
81  }
82
83  Status ListDevices(CallOptions* call_options,
84                     const ListDevicesRequest* request,
85                     ListDevicesResponse* response) override {
86    ::grpc::ClientContext ctx;
87    return Call(&ctx, call_options, request, response,
88                &MasterServiceStub::ListDevices);
89  }
90
91  Status Reset(CallOptions* call_options, const ResetRequest* request,
92               ResetResponse* response) override {
93    ::grpc::ClientContext ctx;
94    return Call(&ctx, call_options, request, response,
95                &MasterServiceStub::Reset);
96  }
97
98 private:
99  // Start tracing, attaching a unique ID to both the trace and the RPC.
100  port::Tracing::TraceMe TraceRpc(StringPiece name,
101                                  ::grpc::ClientContext* ctx) {
102    string trace_id = strings::StrCat(port::Tracing::UniqueId());
103    ctx->AddMetadata(GrpcIdKey(), trace_id);
104    return port::Tracing::TraceMe(name, trace_id);
105  }
106
107  void SetDeadline(::grpc::ClientContext* ctx, int64 time_in_ms) {
108    if (time_in_ms > 0) {
109      ctx->set_deadline(gpr_time_from_millis(time_in_ms, GPR_TIMESPAN));
110    }
111  }
112
113  template <typename Request, typename Response>
114  Status Call(::grpc::ClientContext* ctx, CallOptions* call_options,
115              const Request* request, Response* response,
116              ::grpc::Status (MasterServiceStub::*pfunc)(::grpc::ClientContext*,
117                                                         const Request&,
118                                                         Response*)) {
119    ctx->set_fail_fast(false);
120    SetDeadline(ctx, call_options->GetTimeout());
121    return FromGrpcStatus((stub_.get()->*pfunc)(ctx, *request, response));
122  }
123
124  std::unique_ptr<MasterServiceStub> stub_;
125};
126
127MasterInterface* NewGrpcMaster(const SharedGrpcChannelPtr& channel) {
128  return new GrpcRemoteMaster(channel);
129}
130
131}  // namespace tensorflow
132