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 google::protobuf::util::TimeUtil;
  53
  54 /*
  55  * proto conversion
  56  */
  57
  58 static grpc::Status unmarshal_value_list(const collectd::types::ValueList &msg, value_list_t *vl)
  59 {
  60         vl->time = NS_TO_CDTIME_T(TimeUtil::TimestampToNanoseconds(msg.time()));
  61         vl->interval = NS_TO_CDTIME_T(TimeUtil::DurationToNanoseconds(msg.interval()));
  62
  63         std::string s;
  64
  65         s = msg.host();
  66         if (!s.length())
  67                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
  68                                 grpc::string("missing host name"));
  69         sstrncpy(vl->host, s.c_str(), sizeof(vl->host));
  70
  71         s = msg.plugin();
  72         if (!s.length())
  73                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
  74                                 grpc::string("missing plugin name"));
  75         sstrncpy(vl->plugin, s.c_str(), sizeof(vl->plugin));
  76
  77         s = msg.type();
  78         if (!s.length())
  79                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
  80                                 grpc::string("missing type name"));
  81         sstrncpy(vl->type, s.c_str(), sizeof(vl->type));
  82
  83         s = msg.plugin_instance();
  84         if (s.length())
  85                 sstrncpy(vl->plugin_instance, s.c_str(), sizeof(vl->plugin_instance));
  86
  87         s = msg.type_instance();
  88         if (s.length())
  89                 sstrncpy(vl->type_instance, s.c_str(), sizeof(vl->type_instance));
  90
  91         value_t *values = NULL;
  92         size_t values_len = 0;
  93         auto status = grpc::Status::OK;
  94
  95         for (auto v : msg.value()) {
  96                 value_t *val = (value_t *)realloc(values, (values_len + 1) * sizeof(*values));
  97                 if (!val) {
  98                         status = grpc::Status(grpc::StatusCode::RESOURCE_EXHAUSTED,
  99                                         grpc::string("failed to allocate values array"));
 100                         break;
 101                 }
 102
 103                 values = val;
 104                 val = values + values_len;
 105                 values_len++;
 106
 107                 switch (v.value_case()) {
 108                 case collectd::types::Value::ValueCase::kCounter:
 109                         val->counter = counter_t(v.counter());
 110                         break;
 111                 case collectd::types::Value::ValueCase::kGauge:
 112                         val->gauge = gauge_t(v.gauge());
 113                         break;
 114                 case collectd::types::Value::ValueCase::kDerive:
 115                         val->derive = derive_t(v.derive());
 116                         break;
 117                 case collectd::types::Value::ValueCase::kAbsolute:
 118                         val->absolute = absolute_t(v.absolute());
 119                         break;
 120                 default:
 121                         status = grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 122                                         grpc::string("unkown value type"));
 123                         break;
 124                 }
 125
 126                 if (!status.ok())
 127                         break;
 128         }
 129         if (status.ok()) {
 130                 vl->values = values;
 131                 vl->values_len = values_len;
 132         }
 133         else if (values) {
 134                 free(values);
 135         }
 136
 137         return status;
 138 } /* unmarshal_value_list() */
 139
 140 /*
 141  * request call objects
 142  */
 143
 144 class Call
 145 {
 146 public:
 147         Call(collectd::Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 148                 : service_(service), cq_(cq), status_(CREATE)
 149         { }
 150
 151         virtual ~Call()
 152         { }
 153
 154         void Handle()
 155         {
 156                 if (status_ == CREATE) {
 157                         Create();
 158                         status_ = PROCESS;
 159                 }
 160                 else if (status_ == PROCESS) {
 161                         Process();
 162                         status_ = FINISH;
 163                 }
 164                 else {
 165                         GPR_ASSERT(status_ == FINISH);
 166                         Finish();
 167                 }
 168         } /* Handle() */
 169
 170 protected:
 171         virtual void Create() = 0;
 172         virtual void Process() = 0;
 173         virtual void Finish() = 0;
 174
 175         collectd::Collectd::AsyncService *service_;
 176         grpc::ServerCompletionQueue *cq_;
 177         grpc::ServerContext ctx_;
 178
 179 private:
 180         enum CallStatus { CREATE, PROCESS, FINISH };
 181         CallStatus status_;
 182 }; /* class Call */
 183
 184 class DispatchValuesCall : public Call
 185 {
 186 public:
 187         DispatchValuesCall(collectd::Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 188                 : Call(service, cq), responder_(&ctx_)
 189         {
 190                 Handle();
 191         } /* DispatchValuesCall() */
 192
 193         virtual ~DispatchValuesCall()
 194         { }
 195
 196 private:
 197         void Create()
 198         {
 199                 service_->RequestDispatchValues(&ctx_, &request_, &responder_, cq_, cq_, this);
 200         } /* Create() */
 201
 202         void Process()
 203         {
 204                 // Add a new request object to the queue.
 205                 new DispatchValuesCall(service_, cq_);
 206
 207                 value_list_t vl = VALUE_LIST_INIT;
 208                 auto status = unmarshal_value_list(request_.values(), &vl);
 209                 if (!status.ok()) {
 210                         responder_.Finish(reply_, status, this);
 211                         return;
 212                 }
 213
 214                 if (plugin_dispatch_values(&vl))
 215                         status = grpc::Status(grpc::StatusCode::INTERNAL,
 216                                         grpc::string("failed to enqueue values for writing"));
 217
 218                 responder_.Finish(reply_, status, this);
 219         } /* Process() */
 220
 221         void Finish()
 222         {
 223                 delete this;
 224         } /* Finish() */
 225
 226         collectd::DispatchValuesRequest request_;
 227         collectd::DispatchValuesReply reply_;
 228
 229         grpc::ServerAsyncResponseWriter<collectd::DispatchValuesReply> responder_;
 230 }; /* class DispatchValuesCall */
 231
 232 class ListValuesCall : public Call
 233 {
 234 public:
 235         ListValuesCall(collectd::Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 236                 : Call(service, cq), responder_(&ctx_)
 237         {
 238                 Handle();
 239         } /* ListValuesCall() */
 240
 241         virtual ~ListValuesCall()
 242         { }
 243
 244 private:
 245         void Create()
 246         {
 247                 service_->RequestListValues(&ctx_, &request_, &responder_, cq_, cq_, this);
 248         } /* Create() */
 249
 250         void Process()
 251         {
 252                 new ListValuesCall(service_, cq_);
 253
 254                 char **names = NULL;
 255                 cdtime_t *times = NULL;
 256                 size_t i, n = 0;
 257
 258                 auto status = grpc::Status::OK;
 259                 if (uc_get_names(&names, &times, &n)) {
 260                         status = grpc::Status(grpc::StatusCode::INTERNAL,
 261                                         grpc::string("failed to retrieve values"));
 262                 }
 263
 264                 for (i = 0; i < n; i++) {
 265                         auto v = reply_.add_value();
 266                         auto t = TimeUtil::NanosecondsToTimestamp(CDTIME_T_TO_NS(times[i]));
 267                         v->set_name(names[i]);
 268                         v->set_allocated_time(new google::protobuf::Timestamp(t));
 269                         sfree(names[i]);
 270                 }
 271                 sfree(names);
 272                 sfree(times);
 273
 274                 responder_.Finish(reply_, status, this);
 275         } /* Process() */
 276
 277         void Finish()
 278         {
 279                 delete this;
 280         } /* Finish() */
 281
 282         collectd::ListValuesRequest request_;
 283         collectd::ListValuesReply reply_;
 284
 285         grpc::ServerAsyncResponseWriter<collectd::ListValuesReply> responder_;
 286 }; /* class ListValuesCall */
 287
 288 /*
 289  * gRPC server implementation
 290  */
 291
 292 class CollectdServer final
 293 {
 294 public:
 295         void Start()
 296         {
 297                 // TODO: make configurable
 298                 auto auth = grpc::InsecureServerCredentials();
 299
 300                 grpc::ServerBuilder builder;
 301
 302                 if (!listeners_num) {
 303                         std::string default_addr("0.0.0.0:50051");
 304                         builder.AddListeningPort(default_addr, auth);
 305                         INFO("grpc: Listening on %s", default_addr.c_str());
 306                 }
 307                 else {
 308                         size_t i;
 309                         for (i = 0; i < listeners_num; i++) {
 310                                 auto l = listeners[i];
 311                                 std::string addr(l.addr);
 312                                 addr += std::string(":") + std::string(l.port);
 313                                 builder.AddListeningPort(addr, auth);
 314                                 INFO("grpc: Listening on %s", addr.c_str());
 315                         }
 316                 }
 317
 318                 builder.RegisterAsyncService(&service_);
 319                 cq_ = builder.AddCompletionQueue();
 320                 server_ = builder.BuildAndStart();
 321         } /* Start() */
 322
 323         void Shutdown()
 324         {
 325                 server_->Shutdown();
 326                 cq_->Shutdown();
 327         } /* Shutdown() */
 328
 329         void Mainloop()
 330         {
 331                 // Register request types.
 332                 new DispatchValuesCall(&service_, cq_.get());
 333                 new ListValuesCall(&service_, cq_.get());
 334
 335                 while (true) {
 336                         void *req = NULL;
 337                         bool ok = false;
 338
 339                         if (!cq_->Next(&req, &ok))
 340                                 break; // Queue shut down.
 341                         if (!ok) {
 342                                 ERROR("grpc: Failed to read from queue");
 343                                 break;
 344                         }
 345
 346                         static_cast<Call *>(req)->Handle();
 347                 }
 348         } /* Mainloop() */
 349
 350 private:
 351         collectd::Collectd::AsyncService service_;
 352
 353         std::unique_ptr<grpc::Server> server_;
 354         std::unique_ptr<grpc::ServerCompletionQueue> cq_;
 355 }; /* class CollectdServer */
 356
 357 static CollectdServer *server = nullptr;
 358
 359 /*
 360  * collectd plugin interface
 361  */
 362
 363 extern "C" {
 364         static pthread_t *workers;
 365         static size_t workers_num = 5;
 366
 367         static void *worker_thread(void *arg)
 368         {
 369                 CollectdServer *s = (CollectdServer *)arg;
 370                 s->Mainloop();
 371                 return NULL;
 372         } /* worker_thread() */
 373
 374         static int c_grpc_config_listen(oconfig_item_t *ci)
 375         {
 376                 listener_t *listener;
 377                 int i;
 378
 379                 if ((ci->values_num != 2)
 380                                 || (ci->values[0].type != OCONFIG_TYPE_STRING)
 381                                 || (ci->values[1].type != OCONFIG_TYPE_STRING)) {
 382                         ERROR("grpc: The `%s` config option needs exactly "
 383                                         "two string argument (address and port).", ci->key);
 384                         return -1;
 385                 }
 386
 387                 listener = (listener_t *)realloc(listeners,
 388                                 (listeners_num + 1) * sizeof(*listeners));
 389                 if (!listener) {
 390                         ERROR("grpc: Failed to allocate listeners");
 391                         return -1;
 392                 }
 393                 listeners = listener;
 394                 listener = listeners + listeners_num;
 395                 listeners_num++;
 396
 397                 listener->addr = strdup(ci->values[0].value.string);
 398                 listener->port = strdup(ci->values[1].value.string);
 399
 400                 for (i = 0; i < ci->children_num; i++) {
 401                         oconfig_item_t *child = ci->children + i;
 402                         WARNING("grpc: Option `%s` not allowed in <%s> block.",
 403                                         child->key, ci->key);
 404                 }
 405
 406                 return 0;
 407         } /* c_grpc_config_listen() */
 408
 409         static int c_grpc_config(oconfig_item_t *ci)
 410         {
 411                 int i;
 412
 413                 for (i = 0; i < ci->children_num; i++) {
 414                         oconfig_item_t *child = ci->children + i;
 415
 416                         if (!strcasecmp("Listen", child->key)) {
 417                                 if (c_grpc_config_listen(child))
 418                                         return -1;
 419                         }
 420                         else if (!strcasecmp("WorkerThreads", child->key)) {
 421                                 int n;
 422                                 if (cf_util_get_int(child, &n))
 423                                         return -1;
 424                                 workers_num = (size_t)n;
 425                         }
 426                         else {
 427                                 WARNING("grpc: Option `%s` not allowed here.", child->key);
 428                         }
 429                 }
 430
 431                 return 0;
 432         } /* c_grpc_config() */
 433
 434         static int c_grpc_init(void)
 435         {
 436                 server = new CollectdServer();
 437                 size_t i;
 438
 439                 if (! server) {
 440                         ERROR("grpc: Failed to create server");
 441                         return -1;
 442                 }
 443
 444                 workers = (pthread_t *)calloc(workers_num, sizeof(*workers));
 445                 if (! workers) {
 446                         delete server;
 447                         server = nullptr;
 448
 449                         ERROR("grpc: Failed to allocate worker threads");
 450                         return -1;
 451                 }
 452
 453                 server->Start();
 454                 for (i = 0; i < workers_num; i++) {
 455                         pthread_create(&workers[i], /* attr = */ NULL,
 456                                         worker_thread, server);
 457                 }
 458                 INFO("grpc: Started %zu workers", workers_num);
 459                 return 0;
 460         } /* c_grpc_init() */
 461
 462         static int c_grpc_shutdown(void)
 463         {
 464                 size_t i;
 465
 466                 if (!server)
 467                         return -1;
 468
 469                 server->Shutdown();
 470
 471                 INFO("grpc: Waiting for %zu workers to terminate", workers_num);
 472                 for (i = 0; i < workers_num; i++)
 473                         pthread_join(workers[i], NULL);
 474                 free(workers);
 475                 workers = NULL;
 476                 workers_num = 0;
 477
 478                 delete server;
 479                 server = nullptr;
 480
 481                 return 0;
 482         } /* c_grpc_shutdown() */
 483
 484         void module_register(void)
 485         {
 486                 plugin_register_complex_config("grpc", c_grpc_config);
 487                 plugin_register_init("grpc", c_grpc_init);
 488                 plugin_register_shutdown("grpc", c_grpc_shutdown);
 489         } /* module_register() */
 490 } /* extern "C" */
 491
 492 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */