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 #include <stdlib.h>
20
21 #include <initializer_list>
22 #include <map>
23 #include <memory>
24 #include <string>
25 #include <utility>
26 #include <vector>
27
28 #include "absl/strings/str_format.h"
29
30 #include <grpc/compression.h>
31 #include <grpc/grpc.h>
32 #include <grpc/impl/compression_types.h>
33 #include <grpc/status.h>
34 #include <grpc/support/alloc.h>
35 #include <grpc/support/log.h>
36 #include <grpc/support/time.h>
37 #include <grpcpp/channel.h>
38 #include <grpcpp/client_context.h>
39 #include <grpcpp/impl/interceptor_common.h>
40 #include <grpcpp/impl/sync.h>
41 #include <grpcpp/security/credentials.h>
42 #include <grpcpp/server_context.h>
43 #include <grpcpp/support/client_interceptor.h>
44
45 #include "src/core/lib/gprpp/crash.h"
46
47 namespace grpc {
48
49 class Channel;
50
51 class DefaultGlobalClientCallbacks final
52 : public ClientContext::GlobalCallbacks {
53 public:
~DefaultGlobalClientCallbacks()54 ~DefaultGlobalClientCallbacks() override {}
DefaultConstructor(ClientContext *)55 void DefaultConstructor(ClientContext* /*context*/) override {}
Destructor(ClientContext *)56 void Destructor(ClientContext* /*context*/) override {}
57 };
58
59 static DefaultGlobalClientCallbacks* g_default_client_callbacks =
60 new DefaultGlobalClientCallbacks();
61 static ClientContext::GlobalCallbacks* g_client_callbacks =
62 g_default_client_callbacks;
63
ClientContext()64 ClientContext::ClientContext()
65 : initial_metadata_received_(false),
66 wait_for_ready_(false),
67 wait_for_ready_explicitly_set_(false),
68 call_(nullptr),
69 call_canceled_(false),
70 deadline_(gpr_inf_future(GPR_CLOCK_REALTIME)),
71 census_context_(nullptr),
72 propagate_from_call_(nullptr),
73 compression_algorithm_(GRPC_COMPRESS_NONE),
74 initial_metadata_corked_(false) {
75 g_client_callbacks->DefaultConstructor(this);
76 }
77
~ClientContext()78 ClientContext::~ClientContext() {
79 if (call_) {
80 grpc_call_unref(call_);
81 call_ = nullptr;
82 }
83 g_client_callbacks->Destructor(this);
84 }
85
set_credentials(const std::shared_ptr<CallCredentials> & creds)86 void ClientContext::set_credentials(
87 const std::shared_ptr<CallCredentials>& creds) {
88 creds_ = creds;
89 // If call_ is set, we have already created the call, and set the call
90 // credentials. This should only be done before we have started the batch
91 // for sending initial metadata.
92 if (creds_ != nullptr && call_ != nullptr) {
93 if (!creds_->ApplyToCall(call_)) {
94 SendCancelToInterceptors();
95 grpc_call_cancel_with_status(call_, GRPC_STATUS_CANCELLED,
96 "Failed to set credentials to rpc.",
97 nullptr);
98 }
99 }
100 }
101
FromInternalServerContext(const grpc::ServerContextBase & context,PropagationOptions options)102 std::unique_ptr<ClientContext> ClientContext::FromInternalServerContext(
103 const grpc::ServerContextBase& context, PropagationOptions options) {
104 std::unique_ptr<ClientContext> ctx(new ClientContext);
105 ctx->propagate_from_call_ = context.call_.call;
106 ctx->propagation_options_ = options;
107 return ctx;
108 }
109
FromServerContext(const grpc::ServerContextBase & server_context,PropagationOptions options)110 std::unique_ptr<ClientContext> ClientContext::FromServerContext(
111 const grpc::ServerContextBase& server_context, PropagationOptions options) {
112 return FromInternalServerContext(server_context, options);
113 }
114
FromCallbackServerContext(const grpc::CallbackServerContext & server_context,PropagationOptions options)115 std::unique_ptr<ClientContext> ClientContext::FromCallbackServerContext(
116 const grpc::CallbackServerContext& server_context,
117 PropagationOptions options) {
118 return FromInternalServerContext(server_context, options);
119 }
120
AddMetadata(const std::string & meta_key,const std::string & meta_value)121 void ClientContext::AddMetadata(const std::string& meta_key,
122 const std::string& meta_value) {
123 send_initial_metadata_.insert(std::make_pair(meta_key, meta_value));
124 }
125
set_call(grpc_call * call,const std::shared_ptr<Channel> & channel)126 void ClientContext::set_call(grpc_call* call,
127 const std::shared_ptr<Channel>& channel) {
128 internal::MutexLock lock(&mu_);
129 GPR_ASSERT(call_ == nullptr);
130 call_ = call;
131 channel_ = channel;
132 if (creds_ && !creds_->ApplyToCall(call_)) {
133 // TODO(yashykt): should interceptors also see this status?
134 SendCancelToInterceptors();
135 grpc_call_cancel_with_status(call, GRPC_STATUS_CANCELLED,
136 "Failed to set credentials to rpc.", nullptr);
137 }
138 if (call_canceled_) {
139 SendCancelToInterceptors();
140 grpc_call_cancel(call_, nullptr);
141 }
142 }
143
set_compression_algorithm(grpc_compression_algorithm algorithm)144 void ClientContext::set_compression_algorithm(
145 grpc_compression_algorithm algorithm) {
146 compression_algorithm_ = algorithm;
147 const char* algorithm_name = nullptr;
148 if (!grpc_compression_algorithm_name(algorithm, &algorithm_name)) {
149 grpc_core::Crash(absl::StrFormat(
150 "Name for compression algorithm '%d' unknown.", algorithm));
151 }
152 GPR_ASSERT(algorithm_name != nullptr);
153 AddMetadata(GRPC_COMPRESSION_REQUEST_ALGORITHM_MD_KEY, algorithm_name);
154 }
155
TryCancel()156 void ClientContext::TryCancel() {
157 internal::MutexLock lock(&mu_);
158 if (call_) {
159 SendCancelToInterceptors();
160 grpc_call_cancel(call_, nullptr);
161 } else {
162 call_canceled_ = true;
163 }
164 }
165
SendCancelToInterceptors()166 void ClientContext::SendCancelToInterceptors() {
167 internal::CancelInterceptorBatchMethods cancel_methods;
168 for (size_t i = 0; i < rpc_info_.interceptors_.size(); i++) {
169 rpc_info_.RunInterceptor(&cancel_methods, i);
170 }
171 }
172
peer() const173 std::string ClientContext::peer() const {
174 std::string peer;
175 if (call_) {
176 char* c_peer = grpc_call_get_peer(call_);
177 peer = c_peer;
178 gpr_free(c_peer);
179 }
180 return peer;
181 }
182
SetGlobalCallbacks(GlobalCallbacks * client_callbacks)183 void ClientContext::SetGlobalCallbacks(GlobalCallbacks* client_callbacks) {
184 GPR_ASSERT(g_client_callbacks == g_default_client_callbacks);
185 GPR_ASSERT(client_callbacks != nullptr);
186 GPR_ASSERT(client_callbacks != g_default_client_callbacks);
187 g_client_callbacks = client_callbacks;
188 }
189
190 } // namespace grpc
191