1/*
2 *
3 * Copyright 2015-2016 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_SERVER_BUILDER_IMPL_H
20#define GRPCPP_SERVER_BUILDER_IMPL_H
21
22#include <climits>
23#include <map>
24#include <memory>
25#include <vector>
26
27#include <grpc/impl/codegen/port_platform.h>
28
29#include <grpc/compression.h>
30#include <grpc/support/cpu.h>
31#include <grpc/support/workaround_list.h>
32#include <grpcpp/impl/channel_argument_option.h>
33#include <grpcpp/impl/codegen/server_interceptor.h>
34#include <grpcpp/impl/server_builder_option.h>
35#include <grpcpp/impl/server_builder_plugin.h>
36#include <grpcpp/server.h>
37#include <grpcpp/support/config.h>
38
39struct grpc_resource_quota;
40
41namespace grpc_impl {
42
43class CompletionQueue;
44class ResourceQuota;
45class Server;
46class ServerCompletionQueue;
47class ServerCredentials;
48} // namespace grpc_impl
49
50namespace grpc {
51
52class AsyncGenericService;
53class Service;
54namespace testing {
55class ServerBuilderPluginTest;
56} // namespace testing
57
58namespace internal {
59class ExternalConnectionAcceptorImpl;
60} // namespace internal
61
62#ifndef GRPC_CALLBACK_API_NONEXPERIMENTAL
63namespace experimental {
64#endif
65class CallbackGenericService;
66#ifndef GRPC_CALLBACK_API_NONEXPERIMENTAL
67} // namespace experimental
68#endif
69
70namespace experimental {
71// EXPERIMENTAL API:
72// Interface for a grpc server to build transports with connections created out
73// of band.
74// See ServerBuilder's AddExternalConnectionAcceptor API.
75class ExternalConnectionAcceptor {
76 public:
77 struct NewConnectionParameters {
78 int listener_fd = -1;
79 int fd = -1;
80 ByteBuffer read_buffer; // data intended for the grpc server
81 };
82 virtual ~ExternalConnectionAcceptor() {}
83 // If called before grpc::Server is started or after it is shut down, the new
84 // connection will be closed.
85 virtual void HandleNewConnection(NewConnectionParameters* p) = 0;
86};
87
88} // namespace experimental
89} // namespace grpc
90
91namespace grpc_impl {
92
93/// A builder class for the creation and startup of \a grpc::Server instances.
94class ServerBuilder {
95 public:
96 ServerBuilder();
97 virtual ~ServerBuilder();
98
99 //////////////////////////////////////////////////////////////////////////////
100 // Primary API's
101
102 /// Return a running server which is ready for processing calls.
103 /// Before calling, one typically needs to ensure that:
104 /// 1. a service is registered - so that the server knows what to serve
105 /// (via RegisterService, or RegisterAsyncGenericService)
106 /// 2. a listening port has been added - so the server knows where to receive
107 /// traffic (via AddListeningPort)
108 /// 3. [for async api only] completion queues have been added via
109 /// AddCompletionQueue
110 virtual std::unique_ptr<grpc::Server> BuildAndStart();
111
112 /// Register a service. This call does not take ownership of the service.
113 /// The service must exist for the lifetime of the \a Server instance returned
114 /// by \a BuildAndStart().
115 /// Matches requests with any :authority
116 ServerBuilder& RegisterService(grpc::Service* service);
117
118 /// Enlists an endpoint \a addr (port with an optional IP address) to
119 /// bind the \a grpc::Server object to be created to.
120 ///
121 /// It can be invoked multiple times.
122 ///
123 /// \param addr_uri The address to try to bind to the server in URI form. If
124 /// the scheme name is omitted, "dns:///" is assumed. To bind to any address,
125 /// please use IPv6 any, i.e., [::]:<port>, which also accepts IPv4
126 /// connections. Valid values include dns:///localhost:1234, /
127 /// 192.168.1.1:31416, dns:///[::1]:27182, etc.).
128 /// \param creds The credentials associated with the server.
129 /// \param selected_port[out] If not `nullptr`, gets populated with the port
130 /// number bound to the \a grpc::Server for the corresponding endpoint after
131 /// it is successfully bound by BuildAndStart(), 0 otherwise. AddListeningPort
132 /// does not modify this pointer.
133 ServerBuilder& AddListeningPort(
134 const grpc::string& addr_uri,
135 std::shared_ptr<grpc_impl::ServerCredentials> creds,
136 int* selected_port = nullptr);
137
138 /// Add a completion queue for handling asynchronous services.
139 ///
140 /// Best performance is typically obtained by using one thread per polling
141 /// completion queue.
142 ///
143 /// Caller is required to shutdown the server prior to shutting down the
144 /// returned completion queue. Caller is also required to drain the
145 /// completion queue after shutting it down. A typical usage scenario:
146 ///
147 /// // While building the server:
148 /// ServerBuilder builder;
149 /// ...
150 /// cq_ = builder.AddCompletionQueue();
151 /// server_ = builder.BuildAndStart();
152 ///
153 /// // While shutting down the server;
154 /// server_->Shutdown();
155 /// cq_->Shutdown(); // Always *after* the associated server's Shutdown()!
156 /// // Drain the cq_ that was created
157 /// void* ignored_tag;
158 /// bool ignored_ok;
159 /// while (cq_->Next(&ignored_tag, &ignored_ok)) { }
160 ///
161 /// \param is_frequently_polled This is an optional parameter to inform gRPC
162 /// library about whether this completion queue would be frequently polled
163 /// (i.e. by calling \a Next() or \a AsyncNext()). The default value is
164 /// 'true' and is the recommended setting. Setting this to 'false' (i.e.
165 /// not polling the completion queue frequently) will have a significantly
166 /// negative performance impact and hence should not be used in production
167 /// use cases.
168 std::unique_ptr<grpc_impl::ServerCompletionQueue> AddCompletionQueue(
169 bool is_frequently_polled = true);
170
171 //////////////////////////////////////////////////////////////////////////////
172 // Less commonly used RegisterService variants
173
174 /// Register a service. This call does not take ownership of the service.
175 /// The service must exist for the lifetime of the \a Server instance
176 /// returned by \a BuildAndStart(). Only matches requests with :authority \a
177 /// host
178 ServerBuilder& RegisterService(const grpc::string& host,
179 grpc::Service* service);
180
181 /// Register a generic service.
182 /// Matches requests with any :authority
183 /// This is mostly useful for writing generic gRPC Proxies where the exact
184 /// serialization format is unknown
185 ServerBuilder& RegisterAsyncGenericService(
186 grpc::AsyncGenericService* service);
187
188 //////////////////////////////////////////////////////////////////////////////
189 // Fine control knobs
190
191 /// Set max receive message size in bytes.
192 /// The default is GRPC_DEFAULT_MAX_RECV_MESSAGE_LENGTH.
193 ServerBuilder& SetMaxReceiveMessageSize(int max_receive_message_size) {
194 max_receive_message_size_ = max_receive_message_size;
195 return *this;
196 }
197
198 /// Set max send message size in bytes.
199 /// The default is GRPC_DEFAULT_MAX_SEND_MESSAGE_LENGTH.
200 ServerBuilder& SetMaxSendMessageSize(int max_send_message_size) {
201 max_send_message_size_ = max_send_message_size;
202 return *this;
203 }
204
205 /// \deprecated For backward compatibility.
206 ServerBuilder& SetMaxMessageSize(int max_message_size) {
207 return SetMaxReceiveMessageSize(max_message_size);
208 }
209
210 /// Set the support status for compression algorithms. All algorithms are
211 /// enabled by default.
212 ///
213 /// Incoming calls compressed with an unsupported algorithm will fail with
214 /// \a GRPC_STATUS_UNIMPLEMENTED.
215 ServerBuilder& SetCompressionAlgorithmSupportStatus(
216 grpc_compression_algorithm algorithm, bool enabled);
217
218 /// The default compression level to use for all channel calls in the
219 /// absence of a call-specific level.
220 ServerBuilder& SetDefaultCompressionLevel(grpc_compression_level level);
221
222 /// The default compression algorithm to use for all channel calls in the
223 /// absence of a call-specific level. Note that it overrides any compression
224 /// level set by \a SetDefaultCompressionLevel.
225 ServerBuilder& SetDefaultCompressionAlgorithm(
226 grpc_compression_algorithm algorithm);
227
228 /// Set the attached buffer pool for this server
229 ServerBuilder& SetResourceQuota(
230 const grpc_impl::ResourceQuota& resource_quota);
231
232 ServerBuilder& SetOption(std::unique_ptr<grpc::ServerBuilderOption> option);
233
234 /// Options for synchronous servers.
235 enum SyncServerOption {
236 NUM_CQS, ///< Number of completion queues.
237 MIN_POLLERS, ///< Minimum number of polling threads.
238 MAX_POLLERS, ///< Maximum number of polling threads.
239 CQ_TIMEOUT_MSEC ///< Completion queue timeout in milliseconds.
240 };
241
242 /// Only useful if this is a Synchronous server.
243 ServerBuilder& SetSyncServerOption(SyncServerOption option, int value);
244
245 /// Add a channel argument (an escape hatch to tuning core library parameters
246 /// directly)
247 template <class T>
248 ServerBuilder& AddChannelArgument(const grpc::string& arg, const T& value) {
249 return SetOption(grpc::MakeChannelArgumentOption(arg, value));
250 }
251
252 /// For internal use only: Register a ServerBuilderPlugin factory function.
253 static void InternalAddPluginFactory(
254 std::unique_ptr<grpc::ServerBuilderPlugin> (*CreatePlugin)());
255
256 /// Enable a server workaround. Do not use unless you know what the workaround
257 /// does. For explanation and detailed descriptions of workarounds, see
258 /// doc/workarounds.md.
259 ServerBuilder& EnableWorkaround(grpc_workaround_list id);
260
261 /// NOTE: class experimental_type is not part of the public API of this class.
262 /// TODO(yashykt): Integrate into public API when this is no longer
263 /// experimental.
264 class experimental_type {
265 public:
266 explicit experimental_type(grpc_impl::ServerBuilder* builder)
267 : builder_(builder) {}
268
269 void SetInterceptorCreators(
270 std::vector<std::unique_ptr<
271 grpc::experimental::ServerInterceptorFactoryInterface>>
272 interceptor_creators) {
273 builder_->interceptor_creators_ = std::move(interceptor_creators);
274 }
275
276#ifndef GRPC_CALLBACK_API_NONEXPERIMENTAL
277 /// Register a generic service that uses the callback API.
278 /// Matches requests with any :authority
279 /// This is mostly useful for writing generic gRPC Proxies where the exact
280 /// serialization format is unknown
281 ServerBuilder& RegisterCallbackGenericService(
282 grpc::experimental::CallbackGenericService* service);
283#endif
284
285 enum class ExternalConnectionType {
286 FROM_FD = 0 // in the form of a file descriptor
287 };
288
289 /// Register an acceptor to handle the externally accepted connection in
290 /// grpc server. The returned acceptor can be used to pass the connection
291 /// to grpc server, where a channel will be created with the provided
292 /// server credentials.
293 std::unique_ptr<grpc::experimental::ExternalConnectionAcceptor>
294 AddExternalConnectionAcceptor(ExternalConnectionType type,
295 std::shared_ptr<ServerCredentials> creds);
296
297 private:
298 ServerBuilder* builder_;
299 };
300
301#ifdef GRPC_CALLBACK_API_NONEXPERIMENTAL
302 /// Register a generic service that uses the callback API.
303 /// Matches requests with any :authority
304 /// This is mostly useful for writing generic gRPC Proxies where the exact
305 /// serialization format is unknown
306 ServerBuilder& RegisterCallbackGenericService(
307 grpc::CallbackGenericService* service);
308#endif
309
310 /// NOTE: The function experimental() is not stable public API. It is a view
311 /// to the experimental components of this class. It may be changed or removed
312 /// at any time.
313 experimental_type experimental() { return experimental_type(this); }
314
315 protected:
316 /// Experimental, to be deprecated
317 struct Port {
318 grpc::string addr;
319 std::shared_ptr<grpc_impl::ServerCredentials> creds;
320 int* selected_port;
321 };
322
323 /// Experimental, to be deprecated
324 typedef std::unique_ptr<grpc::string> HostString;
325 struct NamedService {
326 explicit NamedService(grpc::Service* s) : service(s) {}
327 NamedService(const grpc::string& h, grpc::Service* s)
328 : host(new grpc::string(h)), service(s) {}
329 HostString host;
330 grpc::Service* service;
331 };
332
333 /// Experimental, to be deprecated
334 std::vector<Port> ports() { return ports_; }
335
336 /// Experimental, to be deprecated
337 std::vector<NamedService*> services() {
338 std::vector<NamedService*> service_refs;
339 for (auto& ptr : services_) {
340 service_refs.push_back(ptr.get());
341 }
342 return service_refs;
343 }
344
345 /// Experimental, to be deprecated
346 std::vector<grpc::ServerBuilderOption*> options() {
347 std::vector<grpc::ServerBuilderOption*> option_refs;
348 for (auto& ptr : options_) {
349 option_refs.push_back(ptr.get());
350 }
351 return option_refs;
352 }
353
354 private:
355 friend class ::grpc::testing::ServerBuilderPluginTest;
356
357 struct SyncServerSettings {
358 SyncServerSettings()
359 : num_cqs(1), min_pollers(1), max_pollers(2), cq_timeout_msec(10000) {}
360
361 /// Number of server completion queues to create to listen to incoming RPCs.
362 int num_cqs;
363
364 /// Minimum number of threads per completion queue that should be listening
365 /// to incoming RPCs.
366 int min_pollers;
367
368 /// Maximum number of threads per completion queue that can be listening to
369 /// incoming RPCs.
370 int max_pollers;
371
372 /// The timeout for server completion queue's AsyncNext call.
373 int cq_timeout_msec;
374 };
375
376 int max_receive_message_size_;
377 int max_send_message_size_;
378 std::vector<std::unique_ptr<grpc::ServerBuilderOption>> options_;
379 std::vector<std::unique_ptr<NamedService>> services_;
380 std::vector<Port> ports_;
381
382 SyncServerSettings sync_server_settings_;
383
384 /// List of completion queues added via \a AddCompletionQueue method.
385 std::vector<grpc_impl::ServerCompletionQueue*> cqs_;
386
387 std::shared_ptr<grpc_impl::ServerCredentials> creds_;
388 std::vector<std::unique_ptr<grpc::ServerBuilderPlugin>> plugins_;
389 grpc_resource_quota* resource_quota_;
390 grpc::AsyncGenericService* generic_service_{nullptr};
391#ifdef GRPC_CALLBACK_API_NONEXPERIMENTAL
392 grpc::CallbackGenericService* callback_generic_service_{nullptr};
393#else
394 grpc::experimental::CallbackGenericService* callback_generic_service_{
395 nullptr};
396#endif
397
398 struct {
399 bool is_set;
400 grpc_compression_level level;
401 } maybe_default_compression_level_;
402 struct {
403 bool is_set;
404 grpc_compression_algorithm algorithm;
405 } maybe_default_compression_algorithm_;
406 uint32_t enabled_compression_algorithms_bitset_;
407 std::vector<
408 std::unique_ptr<grpc::experimental::ServerInterceptorFactoryInterface>>
409 interceptor_creators_;
410 std::vector<std::shared_ptr<grpc::internal::ExternalConnectionAcceptorImpl>>
411 acceptors_;
412};
413
414} // namespace grpc_impl
415
416#endif // GRPCPP_SERVER_BUILDER_IMPL_H
417