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_values();
 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                 auto name = msg->add_ds_names();
 195                 name->assign(ds->ds[i].name);
 196         }
 197
 198         return grpc::Status::OK;
 199 } /* marshal_value_list */
 200
 201 static grpc::Status unmarshal_value_list(const collectd::types::ValueList &msg, value_list_t *vl)
 202 {
 203         vl->time = NS_TO_CDTIME_T(TimeUtil::TimestampToNanoseconds(msg.time()));
 204         vl->interval = NS_TO_CDTIME_T(TimeUtil::DurationToNanoseconds(msg.interval()));
 205
 206         auto status = unmarshal_ident(msg.identifier(), vl, true);
 207         if (!status.ok())
 208                 return status;
 209
 210         value_t *values = NULL;
 211         size_t values_len = 0;
 212
 213         status = grpc::Status::OK;
 214         for (auto v : msg.values()) {
 215                 value_t *val = (value_t *)realloc(values, (values_len + 1) * sizeof(*values));
 216                 if (!val) {
 217                         status = grpc::Status(grpc::StatusCode::RESOURCE_EXHAUSTED,
 218                                         grpc::string("failed to allocate values array"));
 219                         break;
 220                 }
 221
 222                 values = val;
 223                 val = values + values_len;
 224                 values_len++;
 225
 226                 switch (v.value_case()) {
 227                 case collectd::types::Value::ValueCase::kCounter:
 228                         val->counter = counter_t(v.counter());
 229                         break;
 230                 case collectd::types::Value::ValueCase::kGauge:
 231                         val->gauge = gauge_t(v.gauge());
 232                         break;
 233                 case collectd::types::Value::ValueCase::kDerive:
 234                         val->derive = derive_t(v.derive());
 235                         break;
 236                 case collectd::types::Value::ValueCase::kAbsolute:
 237                         val->absolute = absolute_t(v.absolute());
 238                         break;
 239                 default:
 240                         status = grpc::Status(grpc::StatusCode::INVALID_ARGUMENT,
 241                                         grpc::string("unknown value type"));
 242                         break;
 243                 }
 244
 245                 if (!status.ok())
 246                         break;
 247         }
 248         if (status.ok()) {
 249                 vl->values = values;
 250                 vl->values_len = values_len;
 251         }
 252         else if (values) {
 253                 free(values);
 254         }
 255
 256         return status;
 257 } /* unmarshal_value_list() */
 258
 259 /*
 260  * request call-backs and call objects
 261  */
 262
 263 static grpc::Status Process(grpc::ServerContext *ctx,
 264                 DispatchValuesRequest request, DispatchValuesReply *reply)
 265 {
 266         value_list_t vl = VALUE_LIST_INIT;
 267         auto status = unmarshal_value_list(request.value_list(), &vl);
 268         if (!status.ok())
 269                 return status;
 270
 271         if (plugin_dispatch_values(&vl))
 272                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 273                                 grpc::string("failed to enqueue values for writing"));
 274         return status;
 275 } /* Process(): DispatchValues */
 276
 277 static grpc::Status Process(grpc::ServerContext *ctx,
 278                 QueryValuesRequest request, QueryValuesReply *reply)
 279 {
 280         uc_iter_t *iter;
 281         char *name = NULL;
 282
 283         value_list_t matcher;
 284         auto status = unmarshal_ident(request.identifier(), &matcher, false);
 285         if (!status.ok())
 286                 return status;
 287
 288         if ((iter = uc_get_iterator()) == NULL) {
 289                 return grpc::Status(grpc::StatusCode::INTERNAL,
 290                                 grpc::string("failed to query values: cannot create iterator"));
 291         }
 292
 293         status = grpc::Status::OK;
 294         while (uc_iterator_next(iter, &name) == 0) {
 295                 value_list_t res;
 296                 if (parse_identifier_vl(name, &res) != 0) {
 297                         status = grpc::Status(grpc::StatusCode::INTERNAL,
 298                                         grpc::string("failed to parse identifier"));
 299                         break;
 300                 }
 301
 302                 if (!ident_matches(&res, &matcher))
 303                         continue;
 304
 305                 if (uc_iterator_get_time(iter, &res.time) < 0) {
 306                         status = grpc::Status(grpc::StatusCode::INTERNAL,
 307                                         grpc::string("failed to retrieve value timestamp"));
 308                         break;
 309                 }
 310                 if (uc_iterator_get_interval(iter, &res.interval) < 0) {
 311                         status = grpc::Status(grpc::StatusCode::INTERNAL,
 312                                         grpc::string("failed to retrieve value interval"));
 313                         break;
 314                 }
 315                 if (uc_iterator_get_values(iter, &res.values, &res.values_len) < 0) {
 316                         status = grpc::Status(grpc::StatusCode::INTERNAL,
 317                                         grpc::string("failed to retrieve values"));
 318                         break;
 319                 }
 320
 321                 auto vl = reply->add_value_lists();
 322                 status = marshal_value_list(&res, vl);
 323                 free(res.values);
 324                 if (!status.ok())
 325                         break;
 326         }
 327
 328         uc_iterator_destroy(iter);
 329
 330         return status;
 331 } /* Process(): QueryValues */
 332
 333 class Call
 334 {
 335 public:
 336         Call(Collectd::AsyncService *service, grpc::ServerCompletionQueue *cq)
 337                 : service_(service), cq_(cq), status_(CREATE)
 338         { }
 339
 340         virtual ~Call()
 341         { }
 342
 343         void Handle()
 344         {
 345                 if (status_ == CREATE) {
 346                         Create();
 347                         status_ = PROCESS;
 348                 }
 349                 else if (status_ == PROCESS) {
 350                         Process();
 351                         status_ = FINISH;
 352                 }
 353                 else {
 354                         GPR_ASSERT(status_ == FINISH);
 355                         Finish();
 356                 }
 357         } /* Handle() */
 358
 359 protected:
 360         virtual void Create() = 0;
 361         virtual void Process() = 0;
 362         virtual void Finish() = 0;
 363
 364         Collectd::AsyncService *service_;
 365         grpc::ServerCompletionQueue *cq_;
 366         grpc::ServerContext ctx_;
 367
 368 private:
 369         enum CallStatus { CREATE, PROCESS, FINISH };
 370         CallStatus status_;
 371 }; /* class Call */
 372
 373 template<typename RequestT, typename ReplyT>
 374 class RpcCall final : public Call
 375 {
 376         typedef void (Collectd::AsyncService::*CreatorT)(grpc::ServerContext *,
 377                         RequestT *, grpc::ServerAsyncResponseWriter<ReplyT> *,
 378                         grpc::CompletionQueue *, grpc::ServerCompletionQueue *, void *);
 379
 380 public:
 381         RpcCall(Collectd::AsyncService *service,
 382                         CreatorT creator, grpc::ServerCompletionQueue *cq)
 383                 : Call(service, cq), creator_(creator), responder_(&ctx_)
 384         {
 385                 Handle();
 386         } /* RpcCall() */
 387
 388         virtual ~RpcCall()
 389         { }
 390
 391 private:
 392         void Create()
 393         {
 394                 (service_->*creator_)(&ctx_, &request_, &responder_, cq_, cq_, this);
 395         } /* Create() */
 396
 397         void Process()
 398         {
 399                 // Add a new request object to the queue.
 400                 new RpcCall<RequestT, ReplyT>(service_, creator_, cq_);
 401                 grpc::Status status = ::Process(&ctx_, request_, &reply_);
 402                 responder_.Finish(reply_, status, this);
 403         } /* Process() */
 404
 405         void Finish()
 406         {
 407                 delete this;
 408         } /* Finish() */
 409
 410         CreatorT creator_;
 411
 412         RequestT request_;
 413         ReplyT reply_;
 414
 415         grpc::ServerAsyncResponseWriter<ReplyT> responder_;
 416 }; /* class RpcCall */
 417
 418 /*
 419  * gRPC server implementation
 420  */
 421
 422 class CollectdServer final
 423 {
 424 public:
 425         void Start()
 426         {
 427                 auto auth = grpc::InsecureServerCredentials();
 428
 429                 grpc::ServerBuilder builder;
 430
 431                 if (listeners.empty()) {
 432                         builder.AddListeningPort(default_addr, auth);
 433                         INFO("grpc: Listening on %s", default_addr.c_str());
 434                 }
 435                 else {
 436                         for (auto l : listeners) {
 437                                 grpc::string addr = l.addr + ":" + l.port;
 438
 439                                 auto use_ssl = grpc::string("");
 440                                 auto a = auth;
 441                                 if (l.ssl != nullptr) {
 442                                         use_ssl = grpc::string(" (SSL enabled)");
 443                                         a = grpc::SslServerCredentials(*l.ssl);
 444                                 }
 445
 446                                 builder.AddListeningPort(addr, a);
 447                                 INFO("grpc: Listening on %s%s", addr.c_str(), use_ssl.c_str());
 448                         }
 449                 }
 450
 451                 builder.RegisterService(&service_);
 452                 cq_ = builder.AddCompletionQueue();
 453                 server_ = builder.BuildAndStart();
 454         } /* Start() */
 455
 456         void Shutdown()
 457         {
 458                 server_->Shutdown();
 459                 cq_->Shutdown();
 460         } /* Shutdown() */
 461
 462         void Mainloop()
 463         {
 464                 // Register request types.
 465                 new RpcCall<DispatchValuesRequest, DispatchValuesReply>(&service_,
 466                                 &Collectd::AsyncService::RequestDispatchValues, cq_.get());
 467                 new RpcCall<QueryValuesRequest, QueryValuesReply>(&service_,
 468                                 &Collectd::AsyncService::RequestQueryValues, cq_.get());
 469
 470                 while (true) {
 471                         void *req = NULL;
 472                         bool ok = false;
 473
 474                         if (!cq_->Next(&req, &ok))
 475                                 break; // Queue shut down.
 476                         if (!ok) {
 477                                 ERROR("grpc: Failed to read from queue");
 478                                 break;
 479                         }
 480
 481                         static_cast<Call *>(req)->Handle();
 482                 }
 483         } /* Mainloop() */
 484
 485 private:
 486         Collectd::AsyncService service_;
 487
 488         std::unique_ptr<grpc::Server> server_;
 489         std::unique_ptr<grpc::ServerCompletionQueue> cq_;
 490 }; /* class CollectdServer */
 491
 492 static CollectdServer *server = nullptr;
 493
 494 /*
 495  * collectd plugin interface
 496  */
 497
 498 extern "C" {
 499         static pthread_t *workers;
 500         static size_t workers_num = 5;
 501
 502         static void *worker_thread(void *arg)
 503         {
 504                 CollectdServer *s = (CollectdServer *)arg;
 505                 s->Mainloop();
 506                 return NULL;
 507         } /* worker_thread() */
 508
 509         static int c_grpc_config_listen(oconfig_item_t *ci)
 510         {
 511                 if ((ci->values_num != 2)
 512                                 || (ci->values[0].type != OCONFIG_TYPE_STRING)
 513                                 || (ci->values[1].type != OCONFIG_TYPE_STRING)) {
 514                         ERROR("grpc: The `%s` config option needs exactly "
 515                                         "two string argument (address and port).", ci->key);
 516                         return -1;
 517                 }
 518
 519                 auto listener = Listener();
 520                 listener.addr = grpc::string(ci->values[0].value.string);
 521                 listener.port = grpc::string(ci->values[1].value.string);
 522                 listener.ssl = nullptr;
 523
 524                 auto ssl_opts = new(grpc::SslServerCredentialsOptions);
 525                 grpc::SslServerCredentialsOptions::PemKeyCertPair pkcp = {};
 526                 bool use_ssl = false;
 527
 528                 for (int i = 0; i < ci->children_num; i++) {
 529                         oconfig_item_t *child = ci->children + i;
 530
 531                         if (!strcasecmp("EnableSSL", child->key)) {
 532                                 if (cf_util_get_boolean(child, &use_ssl)) {
 533                                         ERROR("grpc: Option `%s` expects a boolean value",
 534                                                         child->key);
 535                                         return -1;
 536                                 }
 537                         }
 538                         else if (!strcasecmp("SSLRootCerts", child->key)) {
 539                                 char *certs = NULL;
 540                                 if (cf_util_get_string(child, &certs)) {
 541                                         ERROR("grpc: Option `%s` expects a string value",
 542                                                         child->key);
 543                                         return -1;
 544                                 }
 545                                 ssl_opts->pem_root_certs = read_file(certs);
 546                         }
 547                         else if (!strcasecmp("SSLServerKey", child->key)) {
 548                                 char *key = NULL;
 549                                 if (cf_util_get_string(child, &key)) {
 550                                         ERROR("grpc: Option `%s` expects a string value",
 551                                                         child->key);
 552                                         return -1;
 553                                 }
 554                                 pkcp.private_key = read_file(key);
 555                         }
 556                         else if (!strcasecmp("SSLServerCert", child->key)) {
 557                                 char *cert = NULL;
 558                                 if (cf_util_get_string(child, &cert)) {
 559                                         ERROR("grpc: Option `%s` expects a string value",
 560                                                         child->key);
 561                                         return -1;
 562                                 }
 563                                 pkcp.cert_chain = read_file(cert);
 564                         }
 565                         else {
 566                                 WARNING("grpc: Option `%s` not allowed in <%s> block.",
 567                                                 child->key, ci->key);
 568                         }
 569                 }
 570
 571                 ssl_opts->pem_key_cert_pairs.push_back(pkcp);
 572                 if (use_ssl)
 573                         listener.ssl = ssl_opts;
 574                 else
 575                         delete(ssl_opts);
 576
 577                 listeners.push_back(listener);
 578                 return 0;
 579         } /* c_grpc_config_listen() */
 580
 581         static int c_grpc_config(oconfig_item_t *ci)
 582         {
 583                 int i;
 584
 585                 for (i = 0; i < ci->children_num; i++) {
 586                         oconfig_item_t *child = ci->children + i;
 587
 588                         if (!strcasecmp("Listen", child->key)) {
 589                                 if (c_grpc_config_listen(child))
 590                                         return -1;
 591                         }
 592                         else if (!strcasecmp("WorkerThreads", child->key)) {
 593                                 int n;
 594                                 if (cf_util_get_int(child, &n))
 595                                         return -1;
 596                                 workers_num = (size_t)n;
 597                         }
 598                         else {
 599                                 WARNING("grpc: Option `%s` not allowed here.", child->key);
 600                         }
 601                 }
 602
 603                 return 0;
 604         } /* c_grpc_config() */
 605
 606         static int c_grpc_init(void)
 607         {
 608                 server = new CollectdServer();
 609                 size_t i;
 610
 611                 if (! server) {
 612                         ERROR("grpc: Failed to create server");
 613                         return -1;
 614                 }
 615
 616                 workers = (pthread_t *)calloc(workers_num, sizeof(*workers));
 617                 if (! workers) {
 618                         delete server;
 619                         server = nullptr;
 620
 621                         ERROR("grpc: Failed to allocate worker threads");
 622                         return -1;
 623                 }
 624
 625                 server->Start();
 626                 for (i = 0; i < workers_num; i++) {
 627                         plugin_thread_create(&workers[i], /* attr = */ NULL,
 628                                         worker_thread, server);
 629                 }
 630                 INFO("grpc: Started %zu workers", workers_num);
 631                 return 0;
 632         } /* c_grpc_init() */
 633
 634         static int c_grpc_shutdown(void)
 635         {
 636                 size_t i;
 637
 638                 if (!server)
 639                         return -1;
 640
 641                 server->Shutdown();
 642
 643                 INFO("grpc: Waiting for %zu workers to terminate", workers_num);
 644                 for (i = 0; i < workers_num; i++)
 645                         pthread_join(workers[i], NULL);
 646                 free(workers);
 647                 workers = NULL;
 648                 workers_num = 0;
 649
 650                 delete server;
 651                 server = nullptr;
 652
 653                 return 0;
 654         } /* c_grpc_shutdown() */
 655
 656         void module_register(void)
 657         {
 658                 plugin_register_complex_config("grpc", c_grpc_config);
 659                 plugin_register_init("grpc", c_grpc_init);
 660                 plugin_register_shutdown("grpc", c_grpc_shutdown);
 661         } /* module_register() */
 662 } /* extern "C" */
 663
 664 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */