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                         uc_iterator_destroy(iter);
 294                         return grpc::Status(grpc::StatusCode::INTERNAL,
 295                                         grpc::string("failed to parse identifier"));
 296                 }
 297
 298                 if (!ident_matches(&res, &matcher))
 299                         continue;
 300
 301                 if (uc_iterator_get_time(iter, &res.time) < 0) {
 302                         uc_iterator_destroy(iter);
 303                         return grpc::Status(grpc::StatusCode::INTERNAL,
 304                                         grpc::string("failed to retrieve value timestamp"));
 305                 }
 306                 if (uc_iterator_get_interval(iter, &res.interval) < 0) {
 307                         uc_iterator_destroy(iter);
 308                         return grpc::Status(grpc::StatusCode::INTERNAL,
 309                                         grpc::string("failed to retrieve value interval"));
 310                 }
 311                 if (uc_iterator_get_values(iter, &res.values, &res.values_len) < 0) {
 312                         uc_iterator_destroy(iter);
 313                         return grpc::Status(grpc::StatusCode::INTERNAL,
 314                                         grpc::string("failed to retrieve values"));
 315                 }
 316
 317                 auto vl = reply->add_values();
 318                 status = marshal_value_list(&res, vl);
 319                 free(res.values);
 320                 if (!status.ok()) {
 321                         uc_iterator_destroy(iter);
 322                         return status;
 323                 }
 324         }
 325
 326         uc_iterator_destroy(iter);
 327
 328         return grpc::Status::OK;
 329 } /* Process(): QueryValues */
 330
 331 class Call
 332 {
 333 public:
 334         Call(Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 335                 : service_(service), cq_(cq), status_(CREATE)
 336         { }
 337
 338         virtual ~Call()
 339         { }
 340
 341         void Handle()
 342         {
 343                 if (status_ == CREATE) {
 344                         Create();
 345                         status_ = PROCESS;
 346                 }
 347                 else if (status_ == PROCESS) {
 348                         Process();
 349                         status_ = FINISH;
 350                 }
 351                 else {
 352                         GPR_ASSERT(status_ == FINISH);
 353                         Finish();
 354                 }
 355         } /* Handle() */
 356
 357 protected:
 358         virtual void Create() = 0;
 359         virtual void Process() = 0;
 360         virtual void Finish() = 0;
 361
 362         Collectd::AsyncService *service_;
 363         grpc::ServerCompletionQueue *cq_;
 364         grpc::ServerContext ctx_;
 365
 366 private:
 367         enum CallStatus { CREATE, PROCESS, FINISH };
 368         CallStatus status_;
 369 }; /* class Call */
 370
 371 template<typename RequestT, typename ReplyT>
 372 class RpcCall final : public Call
 373 {
 374         typedef void (Collectd::AsyncService::*CreatorT)(grpc::ServerContext *,
 375                         RequestT *, grpc::ServerAsyncResponseWriter<ReplyT> *,
 376                         grpc::CompletionQueue *, grpc::ServerCompletionQueue *, void *);
 377
 378 public:
 379         RpcCall(Collectd::AsyncService *service,
 380                         CreatorT creator, grpc::ServerCompletionQueue *cq)
 381                 : Call(service, cq), creator_(creator), responder_(&ctx_)
 382         {
 383                 Handle();
 384         } /* RpcCall() */
 385
 386         virtual ~RpcCall()
 387         { }
 388
 389 private:
 390         void Create()
 391         {
 392                 (service_->*creator_)(&ctx_, &request_, &responder_, cq_, cq_, this);
 393         } /* Create() */
 394
 395         void Process()
 396         {
 397                 // Add a new request object to the queue.
 398                 new RpcCall<RequestT, ReplyT>(service_, creator_, cq_);
 399                 grpc::Status status = ::Process(&ctx_, request_, &reply_);
 400                 responder_.Finish(reply_, status, this);
 401         } /* Process() */
 402
 403         void Finish()
 404         {
 405                 delete this;
 406         } /* Finish() */
 407
 408         CreatorT creator_;
 409
 410         RequestT request_;
 411         ReplyT reply_;
 412
 413         grpc::ServerAsyncResponseWriter<ReplyT> responder_;
 414 }; /* class RpcCall */
 415
 416 /*
 417  * gRPC server implementation
 418  */
 419
 420 class CollectdServer final
 421 {
 422 public:
 423         void Start()
 424         {
 425                 auto auth = grpc::InsecureServerCredentials();
 426
 427                 grpc::ServerBuilder builder;
 428
 429                 if (listeners.empty()) {
 430                         builder.AddListeningPort(default_addr, auth);
 431                         INFO("grpc: Listening on %s", default_addr.c_str());
 432                 }
 433                 else {
 434                         for (auto l : listeners) {
 435                                 grpc::string addr = l.addr + ":" + l.port;
 436
 437                                 auto use_ssl = grpc::string("");
 438                                 auto a = auth;
 439                                 if (l.ssl != nullptr) {
 440                                         use_ssl = grpc::string(" (SSL enabled)");
 441                                         a = grpc::SslServerCredentials(*l.ssl);
 442                                 }
 443
 444                                 builder.AddListeningPort(addr, a);
 445                                 INFO("grpc: Listening on %s%s", addr.c_str(), use_ssl.c_str());
 446                         }
 447                 }
 448
 449                 builder.RegisterService(&service_);
 450                 cq_ = builder.AddCompletionQueue();
 451                 server_ = builder.BuildAndStart();
 452         } /* Start() */
 453
 454         void Shutdown()
 455         {
 456                 server_->Shutdown();
 457                 cq_->Shutdown();
 458         } /* Shutdown() */
 459
 460         void Mainloop()
 461         {
 462                 // Register request types.
 463                 new RpcCall<DispatchValuesRequest, DispatchValuesReply>(&service_,
 464                                 &Collectd::AsyncService::RequestDispatchValues, cq_.get());
 465                 new RpcCall<QueryValuesRequest, QueryValuesReply>(&service_,
 466                                 &Collectd::AsyncService::RequestQueryValues, cq_.get());
 467
 468                 while (true) {
 469                         void *req = NULL;
 470                         bool ok = false;
 471
 472                         if (!cq_->Next(&req, &ok))
 473                                 break; // Queue shut down.
 474                         if (!ok) {
 475                                 ERROR("grpc: Failed to read from queue");
 476                                 break;
 477                         }
 478
 479                         static_cast<Call *>(req)->Handle();
 480                 }
 481         } /* Mainloop() */
 482
 483 private:
 484         Collectd::AsyncService service_;
 485
 486         std::unique_ptr<grpc::Server> server_;
 487         std::unique_ptr<grpc::ServerCompletionQueue> cq_;
 488 }; /* class CollectdServer */
 489
 490 static CollectdServer *server = nullptr;
 491
 492 /*
 493  * collectd plugin interface
 494  */
 495
 496 extern "C" {
 497         static pthread_t *workers;
 498         static size_t workers_num = 5;
 499
 500         static void *worker_thread(void *arg)
 501         {
 502                 CollectdServer *s = (CollectdServer *)arg;
 503                 s->Mainloop();
 504                 return NULL;
 505         } /* worker_thread() */
 506
 507         static int c_grpc_config_listen(oconfig_item_t *ci)
 508         {
 509                 if ((ci->values_num != 2)
 510                                 || (ci->values[0].type != OCONFIG_TYPE_STRING)
 511                                 || (ci->values[1].type != OCONFIG_TYPE_STRING)) {
 512                         ERROR("grpc: The `%s` config option needs exactly "
 513                                         "two string argument (address and port).", ci->key);
 514                         return -1;
 515                 }
 516
 517                 auto listener = Listener();
 518                 listener.addr = grpc::string(ci->values[0].value.string);
 519                 listener.port = grpc::string(ci->values[1].value.string);
 520                 listener.ssl = nullptr;
 521
 522                 auto ssl_opts = new(grpc::SslServerCredentialsOptions);
 523                 grpc::SslServerCredentialsOptions::PemKeyCertPair pkcp = {};
 524                 bool use_ssl = false;
 525
 526                 for (int i = 0; i < ci->children_num; i++) {
 527                         oconfig_item_t *child = ci->children + i;
 528
 529                         if (!strcasecmp("EnableSSL", child->key)) {
 530                                 if (cf_util_get_boolean(child, &use_ssl)) {
 531                                         ERROR("grpc: Option `%s` expects a boolean value",
 532                                                         child->key);
 533                                         return -1;
 534                                 }
 535                         }
 536                         else if (!strcasecmp("SSLRootCerts", child->key)) {
 537                                 char *certs = NULL;
 538                                 if (cf_util_get_string(child, &certs)) {
 539                                         ERROR("grpc: Option `%s` expects a string value",
 540                                                         child->key);
 541                                         return -1;
 542                                 }
 543                                 ssl_opts->pem_root_certs = read_file(certs);
 544                         }
 545                         else if (!strcasecmp("SSLServerKey", child->key)) {
 546                                 char *key = NULL;
 547                                 if (cf_util_get_string(child, &key)) {
 548                                         ERROR("grpc: Option `%s` expects a string value",
 549                                                         child->key);
 550                                         return -1;
 551                                 }
 552                                 pkcp.private_key = read_file(key);
 553                         }
 554                         else if (!strcasecmp("SSLServerCert", child->key)) {
 555                                 char *cert = NULL;
 556                                 if (cf_util_get_string(child, &cert)) {
 557                                         ERROR("grpc: Option `%s` expects a string value",
 558                                                         child->key);
 559                                         return -1;
 560                                 }
 561                                 pkcp.cert_chain = read_file(cert);
 562                         }
 563                         else {
 564                                 WARNING("grpc: Option `%s` not allowed in <%s> block.",
 565                                                 child->key, ci->key);
 566                         }
 567                 }
 568
 569                 ssl_opts->pem_key_cert_pairs.push_back(pkcp);
 570                 if (use_ssl)
 571                         listener.ssl = ssl_opts;
 572                 else
 573                         delete(ssl_opts);
 574
 575                 listeners.push_back(listener);
 576                 return 0;
 577         } /* c_grpc_config_listen() */
 578
 579         static int c_grpc_config(oconfig_item_t *ci)
 580         {
 581                 int i;
 582
 583                 for (i = 0; i < ci->children_num; i++) {
 584                         oconfig_item_t *child = ci->children + i;
 585
 586                         if (!strcasecmp("Listen", child->key)) {
 587                                 if (c_grpc_config_listen(child))
 588                                         return -1;
 589                         }
 590                         else if (!strcasecmp("WorkerThreads", child->key)) {
 591                                 int n;
 592                                 if (cf_util_get_int(child, &n))
 593                                         return -1;
 594                                 workers_num = (size_t)n;
 595                         }
 596                         else {
 597                                 WARNING("grpc: Option `%s` not allowed here.", child->key);
 598                         }
 599                 }
 600
 601                 return 0;
 602         } /* c_grpc_config() */
 603
 604         static int c_grpc_init(void)
 605         {
 606                 server = new CollectdServer();
 607                 size_t i;
 608
 609                 if (! server) {
 610                         ERROR("grpc: Failed to create server");
 611                         return -1;
 612                 }
 613
 614                 workers = (pthread_t *)calloc(workers_num, sizeof(*workers));
 615                 if (! workers) {
 616                         delete server;
 617                         server = nullptr;
 618
 619                         ERROR("grpc: Failed to allocate worker threads");
 620                         return -1;
 621                 }
 622
 623                 server->Start();
 624                 for (i = 0; i < workers_num; i++) {
 625                         plugin_thread_create(&workers[i], /* attr = */ NULL,
 626                                         worker_thread, server);
 627                 }
 628                 INFO("grpc: Started %zu workers", workers_num);
 629                 return 0;
 630         } /* c_grpc_init() */
 631
 632         static int c_grpc_shutdown(void)
 633         {
 634                 size_t i;
 635
 636                 if (!server)
 637                         return -1;
 638
 639                 server->Shutdown();
 640
 641                 INFO("grpc: Waiting for %zu workers to terminate", workers_num);
 642                 for (i = 0; i < workers_num; i++)
 643                         pthread_join(workers[i], NULL);
 644                 free(workers);
 645                 workers = NULL;
 646                 workers_num = 0;
 647
 648                 delete server;
 649                 server = nullptr;
 650
 651                 return 0;
 652         } /* c_grpc_shutdown() */
 653
 654         void module_register(void)
 655         {
 656                 plugin_register_complex_config("grpc", c_grpc_config);
 657                 plugin_register_init("grpc", c_grpc_init);
 658                 plugin_register_shutdown("grpc", c_grpc_shutdown);
 659         } /* module_register() */
 660 } /* extern "C" */
 661
 662 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */