src/grpc.cc

   1 /**
   2  * collectd - src/grpc.cc
   3  * Copyright (C) 2015-2016 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 <fstream>
  31 #include <iostream>
  32 #include <vector>
  33
  34 #include "collectd.grpc.pb.h"
  35
  36 extern "C" {
  37 #include <fnmatch.h>
  38 #include <stdbool.h>
  39
  40 #include "collectd.h"
  41 #include "common.h"
  42 #include "configfile.h"
  43 #include "plugin.h"
  44
  45 #include "daemon/utils_cache.h"
  46 }
  47
  48 using collectd::Collectd;
  49
  50 using collectd::DispatchValuesRequest;
  51 using collectd::DispatchValuesReply;
  52 using collectd::QueryValuesRequest;
  53 using collectd::QueryValuesReply;
  54
  55 using google::protobuf::util::TimeUtil;
  56
  57 /*
  58  * private types
  59  */
  60
  61 struct Listener {
  62         grpc::string addr;
  63         grpc::string port;
  64
  65         grpc::SslServerCredentialsOptions *ssl;
  66 };
  67 static std::vector<Listener> listeners;
  68 static grpc::string default_addr("0.0.0.0:50051");
  69
  70 /*
  71  * helper functions
  72  */
  73
  74 static bool ident_matches(const value_list_t *vl, const value_list_t *matcher)
  75 {
  76         if (fnmatch(matcher->host, vl->host, 0))
  77                 return false;
  78
  79         if (fnmatch(matcher->plugin, vl->plugin, 0))
  80                 return false;
  81         if (fnmatch(matcher->plugin_instance, vl->plugin_instance, 0))
  82                 return false;
  83
  84         if (fnmatch(matcher->type, vl->type, 0))
  85                 return false;
  86         if (fnmatch(matcher->type_instance, vl->type_instance, 0))
  87                 return false;
  88
  89         return true;
  90 } /* ident_matches */
  91
  92 static grpc::string read_file(const char *filename)
  93 {
  94         std::ifstream f;
  95         grpc::string s, content;
  96
  97         f.open(filename);
  98         if (!f.is_open()) {
  99                 ERROR("grpc: Failed to open '%s'", filename);
 100                 return "";
 101         }
 102
 103         while (std::getline(f, s)) {
 104                 content += s;
 105                 content.push_back('\n');
 106         }
 107         f.close();
 108         return content;
 109 } /* read_file */
 110
 111 /*
 112  * proto conversion
 113  */
 114
 115 static void marshal_ident(const value_list_t *vl, collectd::types::Identifier *msg)
 116 {
 117         msg->set_host(vl->host);
 118         msg->set_plugin(vl->plugin);
 119         if (vl->plugin_instance[0] != '\0')
 120                 msg->set_plugin_instance(vl->plugin_instance);
 121         msg->set_type(vl->type);
 122         if (vl->type_instance[0] != '\0')
 123                 msg->set_type_instance(vl->type_instance);
 124 } /* marshal_ident */
 125
 126 static grpc::Status unmarshal_ident(const collectd::types::Identifier &msg, value_list_t *vl,
 127                 bool require_fields)
 128 {
 129         std::string s;
 130
 131         s = msg.host();
 132         if (!s.length() && require_fields)
 133                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 134                                 grpc::string("missing host name"));
 135         sstrncpy(vl->host, s.c_str(), sizeof(vl->host));
 136
 137         s = msg.plugin();
 138         if (!s.length() && require_fields)
 139                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 140                                 grpc::string("missing plugin name"));
 141         sstrncpy(vl->plugin, s.c_str(), sizeof(vl->plugin));
 142
 143         s = msg.type();
 144         if (!s.length() && require_fields)
 145                 return grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 146                                 grpc::string("missing type name"));
 147         sstrncpy(vl->type, s.c_str(), sizeof(vl->type));
 148
 149         s = msg.plugin_instance();
 150         sstrncpy(vl->plugin_instance, s.c_str(), sizeof(vl->plugin_instance));
 151
 152         s = msg.type_instance();
 153         sstrncpy(vl->type_instance, s.c_str(), sizeof(vl->type_instance));
 154
 155         return grpc::Status::OK;
 156 } /* unmarshal_ident() */
 157
 158 static grpc::Status marshal_value_list(const value_list_t *vl, collectd::types::ValueList *msg)
 159 {
 160         auto id = msg->mutable_identifier();
 161         marshal_ident(vl, id);
 162
 163         auto ds = plugin_get_ds(vl->type);
 164         if ((ds == NULL) || (ds->ds_num != vl->values_len)) {
 165                 return grpc::Status(grpc::StatusCode::INTERNAL,
 166                                 grpc::string("failed to retrieve data-set for values"));
 167         }
 168
 169         auto t = TimeUtil::NanosecondsToTimestamp(CDTIME_T_TO_NS(vl->time));
 170         auto d = TimeUtil::NanosecondsToDuration(CDTIME_T_TO_NS(vl->interval));
 171         msg->set_allocated_time(new google::protobuf::Timestamp(t));
 172         msg->set_allocated_interval(new google::protobuf::Duration(d));
 173
 174         for (size_t i = 0; i < vl->values_len; ++i) {
 175                 auto v = msg->add_value();
 176                 switch (ds->ds[i].type) {
 177                         case DS_TYPE_COUNTER:
 178                                 v->set_counter(vl->values[i].counter);
 179                                 break;
 180                         case DS_TYPE_GAUGE:
 181                                 v->set_gauge(vl->values[i].gauge);
 182                                 break;
 183                         case DS_TYPE_DERIVE:
 184                                 v->set_derive(vl->values[i].derive);
 185                                 break;
 186                         case DS_TYPE_ABSOLUTE:
 187                                 v->set_absolute(vl->values[i].absolute);
 188                                 break;
 189                         default:
 190                                 return grpc::Status(grpc::StatusCode::INTERNAL,
 191                                                 grpc::string("unknown value type"));
 192                 }
 193         }
 194
 195         return grpc::Status::OK;
 196 } /* marshal_value_list */
 197
 198 static grpc::Status unmarshal_value_list(const collectd::types::ValueList &msg, value_list_t *vl)
 199 {
 200         vl->time = NS_TO_CDTIME_T(TimeUtil::TimestampToNanoseconds(msg.time()));
 201         vl->interval = NS_TO_CDTIME_T(TimeUtil::DurationToNanoseconds(msg.interval()));
 202
 203         auto status = unmarshal_ident(msg.identifier(), vl, true);
 204         if (!status.ok())
 205                 return status;
 206
 207         value_t *values = NULL;
 208         size_t values_len = 0;
 209
 210         status = grpc::Status::OK;
 211         for (auto v : msg.value()) {
 212                 value_t *val = (value_t *)realloc(values, (values_len + 1) * sizeof(*values));
 213                 if (!val) {
 214                         status = grpc::Status(grpc::StatusCode::RESOURCE_EXHAUSTED,
 215                                         grpc::string("failed to allocate values array"));
 216                         break;
 217                 }
 218
 219                 values = val;
 220                 val = values + values_len;
 221                 values_len++;
 222
 223                 switch (v.value_case()) {
 224                 case collectd::types::Value::ValueCase::kCounter:
 225                         val->counter = counter_t(v.counter());
 226                         break;
 227                 case collectd::types::Value::ValueCase::kGauge:
 228                         val->gauge = gauge_t(v.gauge());
 229                         break;
 230                 case collectd::types::Value::ValueCase::kDerive:
 231                         val->derive = derive_t(v.derive());
 232                         break;
 233                 case collectd::types::Value::ValueCase::kAbsolute:
 234                         val->absolute = absolute_t(v.absolute());
 235                         break;
 236                 default:
 237                         status = grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 238                                         grpc::string("unknown value type"));
 239                         break;
 240                 }
 241
 242                 if (!status.ok())
 243                         break;
 244         }
 245         if (status.ok()) {
 246                 vl->values = values;
 247                 vl->values_len = values_len;
 248         }
 249         else if (values) {
 250                 free(values);
 251         }
 252
 253         return status;
 254 } /* unmarshal_value_list() */
 255
 256 /*
 257  * request call-backs and call objects
 258  */
 259
 260 static grpc::Status Process(grpc::ServerContext *ctx,
 261                 DispatchValuesRequest request, DispatchValuesReply *reply)
 262 {
 263         value_list_t vl = VALUE_LIST_INIT;
 264         auto status = unmarshal_value_list(request.values(), &vl);
 265         if (!status.ok())
 266                 return status;
 267
 268         if (plugin_dispatch_values(&vl))
 269                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 270                                 grpc::string("failed to enqueue values for writing"));
 271         return status;
 272 } /* Process(): DispatchValues */
 273
 274 static grpc::Status Process(grpc::ServerContext *ctx,
 275                 QueryValuesRequest request, QueryValuesReply *reply)
 276 {
 277         uc_iter_t *iter;
 278         char *name = NULL;
 279
 280         value_list_t matcher;
 281         auto status = unmarshal_ident(request.identifier(), &matcher, false);
 282         if (!status.ok())
 283                 return status;
 284
 285         if ((iter = uc_get_iterator()) == NULL) {
 286                 return grpc::Status(grpc::StatusCode::INTERNAL,
 287                                 grpc::string("failed to query values: cannot create iterator"));
 288         }
 289
 290         while (uc_iterator_next(iter, &name) == 0) {
 291                 value_list_t res;
 292                 if (parse_identifier_vl(name, &res) != 0)
 293                         return grpc::Status(grpc::StatusCode::INTERNAL,
 294                                         grpc::string("failed to parse identifier"));
 295
 296                 if (!ident_matches(&res, &matcher))
 297                         continue;
 298
 299                 if (uc_iterator_get_time(iter, &res.time) < 0)
 300                         return grpc::Status(grpc::StatusCode::INTERNAL,
 301                                         grpc::string("failed to retrieve value timestamp"));
 302                 if (uc_iterator_get_interval(iter, &res.interval) < 0)
 303                         return grpc::Status(grpc::StatusCode::INTERNAL,
 304                                         grpc::string("failed to retrieve value interval"));
 305                 if (uc_iterator_get_values(iter, &res.values, &res.values_len) < 0)
 306                         return grpc::Status(grpc::StatusCode::INTERNAL,
 307                                         grpc::string("failed to retrieve values"));
 308
 309                 auto vl = reply->add_values();
 310                 status = marshal_value_list(&res, vl);
 311                 free(res.values);
 312                 if (!status.ok())
 313                         return status;
 314         }
 315
 316         uc_iterator_destroy(iter);
 317
 318         return grpc::Status::OK;
 319 } /* Process(): QueryValues */
 320
 321 class Call
 322 {
 323 public:
 324         Call(Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 325                 : service_(service), cq_(cq), status_(CREATE)
 326         { }
 327
 328         virtual ~Call()
 329         { }
 330
 331         void Handle()
 332         {
 333                 if (status_ == CREATE) {
 334                         Create();
 335                         status_ = PROCESS;
 336                 }
 337                 else if (status_ == PROCESS) {
 338                         Process();
 339                         status_ = FINISH;
 340                 }
 341                 else {
 342                         GPR_ASSERT(status_ == FINISH);
 343                         Finish();
 344                 }
 345         } /* Handle() */
 346
 347 protected:
 348         virtual void Create() = 0;
 349         virtual void Process() = 0;
 350         virtual void Finish() = 0;
 351
 352         Collectd::AsyncService *service_;
 353         grpc::ServerCompletionQueue *cq_;
 354         grpc::ServerContext ctx_;
 355
 356 private:
 357         enum CallStatus { CREATE, PROCESS, FINISH };
 358         CallStatus status_;
 359 }; /* class Call */
 360
 361 template<typename RequestT, typename ReplyT>
 362 class RpcCall final : public Call
 363 {
 364         typedef void (Collectd::AsyncService::*CreatorT)(grpc::ServerContext *,
 365                         RequestT *, grpc::ServerAsyncResponseWriter<ReplyT> *,
 366                         grpc::CompletionQueue *, grpc::ServerCompletionQueue *, void *);
 367
 368 public:
 369         RpcCall(Collectd::AsyncService *service,
 370                         CreatorT creator, grpc::ServerCompletionQueue *cq)
 371                 : Call(service, cq), creator_(creator), responder_(&ctx_)
 372         {
 373                 Handle();
 374         } /* RpcCall() */
 375
 376         virtual ~RpcCall()
 377         { }
 378
 379 private:
 380         void Create()
 381         {
 382                 (service_->*creator_)(&ctx_, &request_, &responder_, cq_, cq_, this);
 383         } /* Create() */
 384
 385         void Process()
 386         {
 387                 // Add a new request object to the queue.
 388                 new RpcCall<RequestT, ReplyT>(service_, creator_, cq_);
 389                 grpc::Status status = ::Process(&ctx_, request_, &reply_);
 390                 responder_.Finish(reply_, status, this);
 391         } /* Process() */
 392
 393         void Finish()
 394         {
 395                 delete this;
 396         } /* Finish() */
 397
 398         CreatorT creator_;
 399
 400         RequestT request_;
 401         ReplyT reply_;
 402
 403         grpc::ServerAsyncResponseWriter<ReplyT> responder_;
 404 }; /* class RpcCall */
 405
 406 /*
 407  * gRPC server implementation
 408  */
 409
 410 class CollectdServer final
 411 {
 412 public:
 413         void Start()
 414         {
 415                 auto auth = grpc::InsecureServerCredentials();
 416
 417                 grpc::ServerBuilder builder;
 418
 419                 if (listeners.empty()) {
 420                         builder.AddListeningPort(default_addr, auth);
 421                         INFO("grpc: Listening on %s", default_addr.c_str());
 422                 }
 423                 else {
 424                         for (auto l : listeners) {
 425                                 grpc::string addr = l.addr + ":" + l.port;
 426
 427                                 auto use_ssl = grpc::string("");
 428                                 auto a = auth;
 429                                 if (l.ssl != nullptr) {
 430                                         use_ssl = grpc::string(" (SSL enabled)");
 431                                         a = grpc::SslServerCredentials(*l.ssl);
 432                                 }
 433
 434                                 builder.AddListeningPort(addr, a);
 435                                 INFO("grpc: Listening on %s%s", addr.c_str(), use_ssl.c_str());
 436                         }
 437                 }
 438
 439                 builder.RegisterService(&service_);
 440                 cq_ = builder.AddCompletionQueue();
 441                 server_ = builder.BuildAndStart();
 442         } /* Start() */
 443
 444         void Shutdown()
 445         {
 446                 server_->Shutdown();
 447                 cq_->Shutdown();
 448         } /* Shutdown() */
 449
 450         void Mainloop()
 451         {
 452                 // Register request types.
 453                 new RpcCall<DispatchValuesRequest, DispatchValuesReply>(&service_,
 454                                 &Collectd::AsyncService::RequestDispatchValues, cq_.get());
 455                 new RpcCall<QueryValuesRequest, QueryValuesReply>(&service_,
 456                                 &Collectd::AsyncService::RequestQueryValues, cq_.get());
 457
 458                 while (true) {
 459                         void *req = NULL;
 460                         bool ok = false;
 461
 462                         if (!cq_->Next(&req, &ok))
 463                                 break; // Queue shut down.
 464                         if (!ok) {
 465                                 ERROR("grpc: Failed to read from queue");
 466                                 break;
 467                         }
 468
 469                         static_cast<Call *>(req)->Handle();
 470                 }
 471         } /* Mainloop() */
 472
 473 private:
 474         Collectd::AsyncService service_;
 475
 476         std::unique_ptr<grpc::Server> server_;
 477         std::unique_ptr<grpc::ServerCompletionQueue> cq_;
 478 }; /* class CollectdServer */
 479
 480 static CollectdServer *server = nullptr;
 481
 482 /*
 483  * collectd plugin interface
 484  */
 485
 486 extern "C" {
 487         static pthread_t *workers;
 488         static size_t workers_num = 5;
 489
 490         static void *worker_thread(void *arg)
 491         {
 492                 CollectdServer *s = (CollectdServer *)arg;
 493                 s->Mainloop();
 494                 return NULL;
 495         } /* worker_thread() */
 496
 497         static int c_grpc_config_listen(oconfig_item_t *ci)
 498         {
 499                 if ((ci->values_num != 2)
 500                                 || (ci->values[0].type != OCONFIG_TYPE_STRING)
 501                                 || (ci->values[1].type != OCONFIG_TYPE_STRING)) {
 502                         ERROR("grpc: The `%s` config option needs exactly "
 503                                         "two string argument (address and port).", ci->key);
 504                         return -1;
 505                 }
 506
 507                 auto listener = Listener();
 508                 listener.addr = grpc::string(ci->values[0].value.string);
 509                 listener.port = grpc::string(ci->values[1].value.string);
 510                 listener.ssl = nullptr;
 511
 512                 auto ssl_opts = new(grpc::SslServerCredentialsOptions);
 513                 grpc::SslServerCredentialsOptions::PemKeyCertPair pkcp = {};
 514                 bool use_ssl = false;
 515
 516                 for (int i = 0; i < ci->children_num; i++) {
 517                         oconfig_item_t *child = ci->children + i;
 518
 519                         if (!strcasecmp("EnableSSL", child->key)) {
 520                                 if (cf_util_get_boolean(child, &use_ssl)) {
 521                                         ERROR("grpc: Option `%s` expects a boolean value",
 522                                                         child->key);
 523                                         return -1;
 524                                 }
 525                         }
 526                         else if (!strcasecmp("SSLRootCerts", child->key)) {
 527                                 char *certs = NULL;
 528                                 if (cf_util_get_string(child, &certs)) {
 529                                         ERROR("grpc: Option `%s` expects a string value",
 530                                                         child->key);
 531                                         return -1;
 532                                 }
 533                                 ssl_opts->pem_root_certs = read_file(certs);
 534                         }
 535                         else if (!strcasecmp("SSLServerKey", child->key)) {
 536                                 char *key = NULL;
 537                                 if (cf_util_get_string(child, &key)) {
 538                                         ERROR("grpc: Option `%s` expects a string value",
 539                                                         child->key);
 540                                         return -1;
 541                                 }
 542                                 pkcp.private_key = read_file(key);
 543                         }
 544                         else if (!strcasecmp("SSLServerCert", child->key)) {
 545                                 char *cert = NULL;
 546                                 if (cf_util_get_string(child, &cert)) {
 547                                         ERROR("grpc: Option `%s` expects a string value",
 548                                                         child->key);
 549                                         return -1;
 550                                 }
 551                                 pkcp.cert_chain = read_file(cert);
 552                         }
 553                         else {
 554                                 WARNING("grpc: Option `%s` not allowed in <%s> block.",
 555                                                 child->key, ci->key);
 556                         }
 557                 }
 558
 559                 ssl_opts->pem_key_cert_pairs.push_back(pkcp);
 560                 if (use_ssl)
 561                         listener.ssl = ssl_opts;
 562                 else
 563                         delete(ssl_opts);
 564
 565                 listeners.push_back(listener);
 566                 return 0;
 567         } /* c_grpc_config_listen() */
 568
 569         static int c_grpc_config(oconfig_item_t *ci)
 570         {
 571                 int i;
 572
 573                 for (i = 0; i < ci->children_num; i++) {
 574                         oconfig_item_t *child = ci->children + i;
 575
 576                         if (!strcasecmp("Listen", child->key)) {
 577                                 if (c_grpc_config_listen(child))
 578                                         return -1;
 579                         }
 580                         else if (!strcasecmp("WorkerThreads", child->key)) {
 581                                 int n;
 582                                 if (cf_util_get_int(child, &n))
 583                                         return -1;
 584                                 workers_num = (size_t)n;
 585                         }
 586                         else {
 587                                 WARNING("grpc: Option `%s` not allowed here.", child->key);
 588                         }
 589                 }
 590
 591                 return 0;
 592         } /* c_grpc_config() */
 593
 594         static int c_grpc_init(void)
 595         {
 596                 server = new CollectdServer();
 597                 size_t i;
 598
 599                 if (! server) {
 600                         ERROR("grpc: Failed to create server");
 601                         return -1;
 602                 }
 603
 604                 workers = (pthread_t *)calloc(workers_num, sizeof(*workers));
 605                 if (! workers) {
 606                         delete server;
 607                         server = nullptr;
 608
 609                         ERROR("grpc: Failed to allocate worker threads");
 610                         return -1;
 611                 }
 612
 613                 server->Start();
 614                 for (i = 0; i < workers_num; i++) {
 615                         plugin_thread_create(&workers[i], /* attr = */ NULL,
 616                                         worker_thread, server);
 617                 }
 618                 INFO("grpc: Started %zu workers", workers_num);
 619                 return 0;
 620         } /* c_grpc_init() */
 621
 622         static int c_grpc_shutdown(void)
 623         {
 624                 size_t i;
 625
 626                 if (!server)
 627                         return -1;
 628
 629                 server->Shutdown();
 630
 631                 INFO("grpc: Waiting for %zu workers to terminate", workers_num);
 632                 for (i = 0; i < workers_num; i++)
 633                         pthread_join(workers[i], NULL);
 634                 free(workers);
 635                 workers = NULL;
 636                 workers_num = 0;
 637
 638                 delete server;
 639                 server = nullptr;
 640
 641                 return 0;
 642         } /* c_grpc_shutdown() */
 643
 644         void module_register(void)
 645         {
 646                 plugin_register_complex_config("grpc", c_grpc_config);
 647                 plugin_register_init("grpc", c_grpc_init);
 648                 plugin_register_shutdown("grpc", c_grpc_shutdown);
 649         } /* module_register() */
 650 } /* extern "C" */
 651
 652 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */