src/grpc.cc

   1 /**
   2  * collectd - src/grpc.cc
   3  * Copyright (C) 2015 Sebastian Harl
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *   Sebastian Harl <sh at tokkee.org>
  25  **/
  26
  27 #include <grpc++/grpc++.h>
  28 #include <google/protobuf/util/time_util.h>
  29
  30 #include "collectd.grpc.pb.h"
  31
  32 extern "C" {
  33 #include <stdbool.h>
  34 #include <pthread.h>
  35
  36 #include "collectd.h"
  37 #include "common.h"
  38 #include "configfile.h"
  39 #include "plugin.h"
  40
  41 #include "daemon/utils_cache.h"
  42
  43         typedef struct {
  44                 char *addr;
  45                 char *port;
  46         } listener_t;
  47
  48         static listener_t *listeners;
  49         static size_t listeners_num;
  50 }
  51
  52 using collectd::Collectd;
  53
  54 using collectd::DispatchValuesRequest;
  55 using collectd::DispatchValuesReply;
  56 using collectd::ListValuesRequest;
  57 using collectd::ListValuesReply;
  58
  59 using google::protobuf::util::TimeUtil;
  60
  61 /*
  62  * proto conversion
  63  */
  64
  65 static grpc::Status unmarshal_value_list(const collectd::types::ValueList &msg, value_list_t *vl)
  66 {
  67         vl->time = NS_TO_CDTIME_T(TimeUtil::TimestampToNanoseconds(msg.time()));
  68         vl->interval = NS_TO_CDTIME_T(TimeUtil::DurationToNanoseconds(msg.interval()));
  69
  70         std::string s;
  71
  72         s = msg.host();
  73         if (!s.length())
  74                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
  75                                 grpc::string("missing host name"));
  76         sstrncpy(vl->host, s.c_str(), sizeof(vl->host));
  77
  78         s = msg.plugin();
  79         if (!s.length())
  80                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
  81                                 grpc::string("missing plugin name"));
  82         sstrncpy(vl->plugin, s.c_str(), sizeof(vl->plugin));
  83
  84         s = msg.type();
  85         if (!s.length())
  86                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
  87                                 grpc::string("missing type name"));
  88         sstrncpy(vl->type, s.c_str(), sizeof(vl->type));
  89
  90         s = msg.plugin_instance();
  91         if (s.length())
  92                 sstrncpy(vl->plugin_instance, s.c_str(), sizeof(vl->plugin_instance));
  93
  94         s = msg.type_instance();
  95         if (s.length())
  96                 sstrncpy(vl->type_instance, s.c_str(), sizeof(vl->type_instance));
  97
  98         value_t *values = NULL;
  99         size_t values_len = 0;
 100         auto status = grpc::Status::OK;
 101
 102         for (auto v : msg.value()) {
 103                 value_t *val = (value_t *)realloc(values, (values_len + 1) * sizeof(*values));
 104                 if (!val) {
 105                         status = grpc::Status(grpc::StatusCode::RESOURCE_EXHAUSTED,
 106                                         grpc::string("failed to allocate values array"));
 107                         break;
 108                 }
 109
 110                 values = val;
 111                 val = values + values_len;
 112                 values_len++;
 113
 114                 switch (v.value_case()) {
 115                 case collectd::types::Value::ValueCase::kCounter:
 116                         val->counter = counter_t(v.counter());
 117                         break;
 118                 case collectd::types::Value::ValueCase::kGauge:
 119                         val->gauge = gauge_t(v.gauge());
 120                         break;
 121                 case collectd::types::Value::ValueCase::kDerive:
 122                         val->derive = derive_t(v.derive());
 123                         break;
 124                 case collectd::types::Value::ValueCase::kAbsolute:
 125                         val->absolute = absolute_t(v.absolute());
 126                         break;
 127                 default:
 128                         status = grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 129                                         grpc::string("unkown value type"));
 130                         break;
 131                 }
 132
 133                 if (!status.ok())
 134                         break;
 135         }
 136         if (status.ok()) {
 137                 vl->values = values;
 138                 vl->values_len = values_len;
 139         }
 140         else if (values) {
 141                 free(values);
 142         }
 143
 144         return status;
 145 } /* unmarshal_value_list() */
 146
 147 /*
 148  * request call-backs and call objects
 149  */
 150
 151 static grpc::Status Process(grpc::ServerContext *ctx,
 152                 DispatchValuesRequest request, DispatchValuesReply *reply)
 153 {
 154         value_list_t vl = VALUE_LIST_INIT;
 155         auto status = unmarshal_value_list(request.values(), &vl);
 156         if (!status.ok())
 157                 return status;
 158
 159         if (plugin_dispatch_values(&vl))
 160                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 161                                 grpc::string("failed to enqueue values for writing"));
 162         return status;
 163 } /* Process(): DispatchValues */
 164
 165 static grpc::Status Process(grpc::ServerContext *ctx,
 166                 ListValuesRequest request, ListValuesReply *reply)
 167 {
 168         char **names = NULL;
 169         cdtime_t *times = NULL;
 170         size_t i, n = 0;
 171
 172         if (uc_get_names(&names, &times, &n))
 173                 return grpc::Status(grpc::StatusCode::INTERNAL,
 174                                 grpc::string("failed to retrieve values"));
 175
 176         for (i = 0; i < n; i++) {
 177                 auto v = reply->add_value();
 178                 auto t = TimeUtil::NanosecondsToTimestamp(CDTIME_T_TO_NS(times[i]));
 179                 v->set_name(names[i]);
 180                 v->set_allocated_time(new google::protobuf::Timestamp(t));
 181                 sfree(names[i]);
 182         }
 183         sfree(names);
 184         sfree(times);
 185
 186         return grpc::Status::OK;
 187 } /* Process(): ListValues */
 188
 189 class Call
 190 {
 191 public:
 192         Call(Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 193                 : service_(service), cq_(cq), status_(CREATE)
 194         { }
 195
 196         virtual ~Call()
 197         { }
 198
 199         void Handle()
 200         {
 201                 if (status_ == CREATE) {
 202                         Create();
 203                         status_ = PROCESS;
 204                 }
 205                 else if (status_ == PROCESS) {
 206                         Process();
 207                         status_ = FINISH;
 208                 }
 209                 else {
 210                         GPR_ASSERT(status_ == FINISH);
 211                         Finish();
 212                 }
 213         } /* Handle() */
 214
 215 protected:
 216         virtual void Create() = 0;
 217         virtual void Process() = 0;
 218         virtual void Finish() = 0;
 219
 220         Collectd::AsyncService *service_;
 221         grpc::ServerCompletionQueue *cq_;
 222         grpc::ServerContext ctx_;
 223
 224 private:
 225         enum CallStatus { CREATE, PROCESS, FINISH };
 226         CallStatus status_;
 227 }; /* class Call */
 228
 229 template<typename RequestT, typename ReplyT>
 230 class RpcCall final : public Call
 231 {
 232         typedef void (Collectd::AsyncService::*CreatorT)(grpc::ServerContext *,
 233                         RequestT *, grpc::ServerAsyncResponseWriter<ReplyT> *,
 234                         grpc::CompletionQueue *, grpc::ServerCompletionQueue *, void *);
 235
 236 public:
 237         RpcCall(Collectd::AsyncService *service,
 238                         CreatorT creator, grpc::ServerCompletionQueue *cq)
 239                 : Call(service, cq), creator_(creator), responder_(&ctx_)
 240         {
 241                 Handle();
 242         } /* RpcCall() */
 243
 244         virtual ~RpcCall()
 245         { }
 246
 247 private:
 248         void Create()
 249         {
 250                 (service_->*creator_)(&ctx_, &request_, &responder_, cq_, cq_, this);
 251         } /* Create() */
 252
 253         void Process()
 254         {
 255                 // Add a new request object to the queue.
 256                 new RpcCall<RequestT, ReplyT>(service_, creator_, cq_);
 257                 grpc::Status status = ::Process(&ctx_, request_, &reply_);
 258                 responder_.Finish(reply_, status, this);
 259         } /* Process() */
 260
 261         void Finish()
 262         {
 263                 delete this;
 264         } /* Finish() */
 265
 266         CreatorT creator_;
 267
 268         RequestT request_;
 269         ReplyT reply_;
 270
 271         grpc::ServerAsyncResponseWriter<ReplyT> responder_;
 272 }; /* class RpcCall */
 273
 274 /*
 275  * gRPC server implementation
 276  */
 277
 278 class CollectdServer final
 279 {
 280 public:
 281         void Start()
 282         {
 283                 // TODO: make configurable
 284                 auto auth = grpc::InsecureServerCredentials();
 285
 286                 grpc::ServerBuilder builder;
 287
 288                 if (!listeners_num) {
 289                         std::string default_addr("0.0.0.0:50051");
 290                         builder.AddListeningPort(default_addr, auth);
 291                         INFO("grpc: Listening on %s", default_addr.c_str());
 292                 }
 293                 else {
 294                         size_t i;
 295                         for (i = 0; i < listeners_num; i++) {
 296                                 auto l = listeners[i];
 297                                 std::string addr(l.addr);
 298                                 addr += std::string(":") + std::string(l.port);
 299                                 builder.AddListeningPort(addr, auth);
 300                                 INFO("grpc: Listening on %s", addr.c_str());
 301                         }
 302                 }
 303
 304                 builder.RegisterService(&service_);
 305                 cq_ = builder.AddCompletionQueue();
 306                 server_ = builder.BuildAndStart();
 307         } /* Start() */
 308
 309         void Shutdown()
 310         {
 311                 server_->Shutdown();
 312                 cq_->Shutdown();
 313         } /* Shutdown() */
 314
 315         void Mainloop()
 316         {
 317                 // Register request types.
 318                 new RpcCall<DispatchValuesRequest, DispatchValuesReply>(&service_,
 319                                 &Collectd::AsyncService::RequestDispatchValues, cq_.get());
 320                 new RpcCall<ListValuesRequest, ListValuesReply>(&service_,
 321                                 &Collectd::AsyncService::RequestListValues, cq_.get());
 322
 323                 while (true) {
 324                         void *req = NULL;
 325                         bool ok = false;
 326
 327                         if (!cq_->Next(&req, &ok))
 328                                 break; // Queue shut down.
 329                         if (!ok) {
 330                                 ERROR("grpc: Failed to read from queue");
 331                                 break;
 332                         }
 333
 334                         static_cast<Call *>(req)->Handle();
 335                 }
 336         } /* Mainloop() */
 337
 338 private:
 339         Collectd::AsyncService service_;
 340
 341         std::unique_ptr<grpc::Server> server_;
 342         std::unique_ptr<grpc::ServerCompletionQueue> cq_;
 343 }; /* class CollectdServer */
 344
 345 static CollectdServer *server = nullptr;
 346
 347 /*
 348  * collectd plugin interface
 349  */
 350
 351 extern "C" {
 352         static pthread_t *workers;
 353         static size_t workers_num = 5;
 354
 355         static void *worker_thread(void *arg)
 356         {
 357                 CollectdServer *s = (CollectdServer *)arg;
 358                 s->Mainloop();
 359                 return NULL;
 360         } /* worker_thread() */
 361
 362         static int c_grpc_config_listen(oconfig_item_t *ci)
 363         {
 364                 listener_t *listener;
 365                 int i;
 366
 367                 if ((ci->values_num != 2)
 368                                 || (ci->values[0].type != OCONFIG_TYPE_STRING)
 369                                 || (ci->values[1].type != OCONFIG_TYPE_STRING)) {
 370                         ERROR("grpc: The `%s` config option needs exactly "
 371                                         "two string argument (address and port).", ci->key);
 372                         return -1;
 373                 }
 374
 375                 listener = (listener_t *)realloc(listeners,
 376                                 (listeners_num + 1) * sizeof(*listeners));
 377                 if (!listener) {
 378                         ERROR("grpc: Failed to allocate listeners");
 379                         return -1;
 380                 }
 381                 listeners = listener;
 382                 listener = listeners + listeners_num;
 383                 listeners_num++;
 384
 385                 listener->addr = strdup(ci->values[0].value.string);
 386                 listener->port = strdup(ci->values[1].value.string);
 387
 388                 for (i = 0; i < ci->children_num; i++) {
 389                         oconfig_item_t *child = ci->children + i;
 390                         WARNING("grpc: Option `%s` not allowed in <%s> block.",
 391                                         child->key, ci->key);
 392                 }
 393
 394                 return 0;
 395         } /* c_grpc_config_listen() */
 396
 397         static int c_grpc_config(oconfig_item_t *ci)
 398         {
 399                 int i;
 400
 401                 for (i = 0; i < ci->children_num; i++) {
 402                         oconfig_item_t *child = ci->children + i;
 403
 404                         if (!strcasecmp("Listen", child->key)) {
 405                                 if (c_grpc_config_listen(child))
 406                                         return -1;
 407                         }
 408                         else if (!strcasecmp("WorkerThreads", child->key)) {
 409                                 int n;
 410                                 if (cf_util_get_int(child, &n))
 411                                         return -1;
 412                                 workers_num = (size_t)n;
 413                         }
 414                         else {
 415                                 WARNING("grpc: Option `%s` not allowed here.", child->key);
 416                         }
 417                 }
 418
 419                 return 0;
 420         } /* c_grpc_config() */
 421
 422         static int c_grpc_init(void)
 423         {
 424                 server = new CollectdServer();
 425                 size_t i;
 426
 427                 if (! server) {
 428                         ERROR("grpc: Failed to create server");
 429                         return -1;
 430                 }
 431
 432                 workers = (pthread_t *)calloc(workers_num, sizeof(*workers));
 433                 if (! workers) {
 434                         delete server;
 435                         server = nullptr;
 436
 437                         ERROR("grpc: Failed to allocate worker threads");
 438                         return -1;
 439                 }
 440
 441                 server->Start();
 442                 for (i = 0; i < workers_num; i++) {
 443                         pthread_create(&workers[i], /* attr = */ NULL,
 444                                         worker_thread, server);
 445                 }
 446                 INFO("grpc: Started %zu workers", workers_num);
 447                 return 0;
 448         } /* c_grpc_init() */
 449
 450         static int c_grpc_shutdown(void)
 451         {
 452                 size_t i;
 453
 454                 if (!server)
 455                         return -1;
 456
 457                 server->Shutdown();
 458
 459                 INFO("grpc: Waiting for %zu workers to terminate", workers_num);
 460                 for (i = 0; i < workers_num; i++)
 461                         pthread_join(workers[i], NULL);
 462                 free(workers);
 463                 workers = NULL;
 464                 workers_num = 0;
 465
 466                 delete server;
 467                 server = nullptr;
 468
 469                 return 0;
 470         } /* c_grpc_shutdown() */
 471
 472         void module_register(void)
 473         {
 474                 plugin_register_complex_config("grpc", c_grpc_config);
 475                 plugin_register_init("grpc", c_grpc_init);
 476                 plugin_register_shutdown("grpc", c_grpc_shutdown);
 477         } /* module_register() */
 478 } /* extern "C" */
 479
 480 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */