1 | /* |
2 | * |
3 | * Copyright 2015 gRPC authors. |
4 | * |
5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
6 | * you may not use this file except in compliance with the License. |
7 | * You may obtain a copy of the License at |
8 | * |
9 | * http://www.apache.org/licenses/LICENSE-2.0 |
10 | * |
11 | * Unless required by applicable law or agreed to in writing, software |
12 | * distributed under the License is distributed on an "AS IS" BASIS, |
13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
14 | * See the License for the specific language governing permissions and |
15 | * limitations under the License. |
16 | * |
17 | */ |
18 | |
19 | #ifndef GRPCPP_CHANNEL_IMPL_H |
20 | #define GRPCPP_CHANNEL_IMPL_H |
21 | |
22 | #include <memory> |
23 | |
24 | #include <grpc/grpc.h> |
25 | #include <grpcpp/impl/call.h> |
26 | #include <grpcpp/impl/codegen/channel_interface.h> |
27 | #include <grpcpp/impl/codegen/client_interceptor.h> |
28 | #include <grpcpp/impl/codegen/completion_queue_impl.h> |
29 | #include <grpcpp/impl/codegen/config.h> |
30 | #include <grpcpp/impl/codegen/grpc_library.h> |
31 | #include <grpcpp/impl/codegen/sync.h> |
32 | |
33 | struct grpc_channel; |
34 | |
35 | namespace grpc { |
36 | |
37 | std::shared_ptr<::grpc_impl::Channel> CreateChannelInternal( |
38 | const grpc::string& host, grpc_channel* c_channel, |
39 | std::vector< |
40 | std::unique_ptr<experimental::ClientInterceptorFactoryInterface>> |
41 | interceptor_creators); |
42 | } // namespace grpc |
43 | namespace grpc_impl { |
44 | |
45 | namespace experimental { |
46 | /// Resets the channel's connection backoff. |
47 | /// TODO(roth): Once we see whether this proves useful, either create a gRFC |
48 | /// and change this to be a method of the Channel class, or remove it. |
49 | void ChannelResetConnectionBackoff(Channel* channel); |
50 | } // namespace experimental |
51 | |
52 | /// Channels represent a connection to an endpoint. Created by \a CreateChannel. |
53 | class Channel final : public ::grpc::ChannelInterface, |
54 | public ::grpc::internal::CallHook, |
55 | public std::enable_shared_from_this<Channel>, |
56 | private ::grpc::GrpcLibraryCodegen { |
57 | public: |
58 | ~Channel(); |
59 | |
60 | /// Get the current channel state. If the channel is in IDLE and |
61 | /// \a try_to_connect is set to true, try to connect. |
62 | grpc_connectivity_state GetState(bool try_to_connect) override; |
63 | |
64 | /// Returns the LB policy name, or the empty string if not yet available. |
65 | grpc::string GetLoadBalancingPolicyName() const; |
66 | |
67 | /// Returns the service config in JSON form, or the empty string if |
68 | /// not available. |
69 | grpc::string GetServiceConfigJSON() const; |
70 | |
71 | private: |
72 | template <class InputMessage, class OutputMessage> |
73 | friend class ::grpc::internal::BlockingUnaryCallImpl; |
74 | friend void experimental::ChannelResetConnectionBackoff(Channel* channel); |
75 | friend std::shared_ptr<Channel> grpc::CreateChannelInternal( |
76 | const grpc::string& host, grpc_channel* c_channel, |
77 | std::vector<std::unique_ptr< |
78 | ::grpc::experimental::ClientInterceptorFactoryInterface>> |
79 | interceptor_creators); |
80 | friend class ::grpc::internal::InterceptedChannel; |
81 | Channel(const grpc::string& host, grpc_channel* c_channel, |
82 | std::vector<std::unique_ptr< |
83 | ::grpc::experimental::ClientInterceptorFactoryInterface>> |
84 | interceptor_creators); |
85 | |
86 | ::grpc::internal::Call CreateCall(const ::grpc::internal::RpcMethod& method, |
87 | ::grpc_impl::ClientContext* context, |
88 | ::grpc_impl::CompletionQueue* cq) override; |
89 | void PerformOpsOnCall(::grpc::internal::CallOpSetInterface* ops, |
90 | ::grpc::internal::Call* call) override; |
91 | void* RegisterMethod(const char* method) override; |
92 | |
93 | void NotifyOnStateChangeImpl(grpc_connectivity_state last_observed, |
94 | gpr_timespec deadline, |
95 | ::grpc_impl::CompletionQueue* cq, |
96 | void* tag) override; |
97 | bool WaitForStateChangeImpl(grpc_connectivity_state last_observed, |
98 | gpr_timespec deadline) override; |
99 | |
100 | ::grpc_impl::CompletionQueue* CallbackCQ() override; |
101 | |
102 | ::grpc::internal::Call CreateCallInternal( |
103 | const ::grpc::internal::RpcMethod& method, |
104 | ::grpc_impl::ClientContext* context, ::grpc_impl::CompletionQueue* cq, |
105 | size_t interceptor_pos) override; |
106 | |
107 | const grpc::string host_; |
108 | grpc_channel* const c_channel_; // owned |
109 | |
110 | // mu_ protects callback_cq_ (the per-channel callbackable completion queue) |
111 | grpc::internal::Mutex mu_; |
112 | |
113 | // callback_cq_ references the callbackable completion queue associated |
114 | // with this channel (if any). It is set on the first call to CallbackCQ(). |
115 | // It is _not owned_ by the channel; ownership belongs with its internal |
116 | // shutdown callback tag (invoked when the CQ is fully shutdown). |
117 | ::grpc_impl::CompletionQueue* callback_cq_ = nullptr; |
118 | |
119 | std::vector< |
120 | std::unique_ptr<::grpc::experimental::ClientInterceptorFactoryInterface>> |
121 | interceptor_creators_; |
122 | }; |
123 | |
124 | } // namespace grpc_impl |
125 | |
126 | #endif // GRPCPP_CHANNEL_IMPL_H |
127 | |