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 <queue>
  33 #include <vector>
  34
  35 #include "collectd.grpc.pb.h"
  36
  37 extern "C" {
  38 #include <fnmatch.h>
  39 #include <stdbool.h>
  40
  41 #include "collectd.h"
  42 #include "common.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::DispatchValuesResponse;
  52 using collectd::QueryValuesRequest;
  53 using collectd::QueryValuesResponse;
  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  * Collectd service
 261  */
 262 class CollectdImpl : public collectd::Collectd::Service {
 263 public:
 264         grpc::Status QueryValues(grpc::ServerContext *ctx, QueryValuesRequest const *req, grpc::ServerWriter<QueryValuesResponse> *writer) override {
 265                 value_list_t match;
 266                 auto status = unmarshal_ident(req->identifier(), &match, false);
 267                 if (!status.ok()) {
 268                         return status;
 269                 }
 270
 271                 std::queue<value_list_t> value_lists;
 272                 status = this->queryValuesRead(&match, &value_lists);
 273                 if (status.ok()) {
 274                         status = this->queryValuesWrite(ctx, writer, &value_lists);
 275                 }
 276
 277                 while (!value_lists.empty()) {
 278                         auto vl = value_lists.front();
 279                         value_lists.pop();
 280                         sfree(vl.values);
 281                 }
 282
 283                 return status;
 284         }
 285
 286         grpc::Status DispatchValues(grpc::ServerContext *ctx,
 287                                                                 grpc::ServerReader<DispatchValuesRequest> *reader,
 288                                                                 DispatchValuesResponse *res) override {
 289                 DispatchValuesRequest req;
 290
 291                 while (reader->Read(&req)) {
 292                         value_list_t vl = VALUE_LIST_INIT;
 293                         auto status = unmarshal_value_list(req.value_list(), &vl);
 294                         if (!status.ok())
 295                                 return status;
 296
 297                         if (plugin_dispatch_values(&vl))
 298                                 return grpc::Status(grpc::StatusCode::INTERNAL,
 299                                                                         grpc::string("failed to enqueue values for writing"));
 300                 }
 301
 302                 res->Clear();
 303                 return grpc::Status::OK;
 304         }
 305
 306 private:
 307         grpc::Status queryValuesRead(value_list_t const *match, std::queue<value_list_t> *value_lists) {
 308                 uc_iter_t *iter;
 309                 if ((iter = uc_get_iterator()) == NULL) {
 310                         return grpc::Status(grpc::StatusCode::INTERNAL,
 311                                                                 grpc::string("failed to query values: cannot create iterator"));
 312                 }
 313
 314                 grpc::Status status = grpc::Status::OK;
 315                 char *name = NULL;
 316                 while (uc_iterator_next(iter, &name) == 0) {
 317                         value_list_t vl;
 318                         if (parse_identifier_vl(name, &vl) != 0) {
 319                                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 320                                                                           grpc::string("failed to parse identifier"));
 321                                 break;
 322                         }
 323
 324                         if (!ident_matches(&vl, match))
 325                                 continue;
 326
 327                         if (uc_iterator_get_time(iter, &vl.time) < 0) {
 328                                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 329                                                                           grpc::string("failed to retrieve value timestamp"));
 330                                 break;
 331                         }
 332                         if (uc_iterator_get_interval(iter, &vl.interval) < 0) {
 333                                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 334                                                                           grpc::string("failed to retrieve value interval"));
 335                                 break;
 336                         }
 337                         if (uc_iterator_get_values(iter, &vl.values, &vl.values_len) < 0) {
 338                                 status = grpc::Status(grpc::StatusCode::INTERNAL,
 339                                                                           grpc::string("failed to retrieve values"));
 340                                 break;
 341                         }
 342
 343                         value_lists->push(vl);
 344                 } // while (uc_iterator_next(iter, &name) == 0)
 345
 346                 uc_iterator_destroy(iter);
 347                 return status;
 348         }
 349
 350         grpc::Status queryValuesWrite(grpc::ServerContext *ctx,
 351                                            grpc::ServerWriter<QueryValuesResponse> *writer,
 352                                            std::queue<value_list_t> *value_lists) {
 353                 while (!value_lists->empty()) {
 354                         auto vl = value_lists->front();
 355                         QueryValuesResponse res;
 356                         res.Clear();
 357
 358                         auto status = marshal_value_list(&vl, res.mutable_value_list());
 359                         if (!status.ok()) {
 360                                 return status;
 361                         }
 362
 363                         if (!writer->Write(res)) {
 364                                 return grpc::Status::CANCELLED;
 365                         }
 366
 367                         value_lists->pop();
 368                         sfree(vl.values);
 369                 }
 370
 371                 return grpc::Status::OK;
 372         }
 373 };
 374
 375 /*
 376  * gRPC server implementation
 377  */
 378 class CollectdServer final
 379 {
 380 public:
 381         void Start()
 382         {
 383                 auto auth = grpc::InsecureServerCredentials();
 384
 385                 grpc::ServerBuilder builder;
 386
 387                 if (listeners.empty()) {
 388                         builder.AddListeningPort(default_addr, auth);
 389                         INFO("grpc: Listening on %s", default_addr.c_str());
 390                 }
 391                 else {
 392                         for (auto l : listeners) {
 393                                 grpc::string addr = l.addr + ":" + l.port;
 394
 395                                 auto use_ssl = grpc::string("");
 396                                 auto a = auth;
 397                                 if (l.ssl != nullptr) {
 398                                         use_ssl = grpc::string(" (SSL enabled)");
 399                                         a = grpc::SslServerCredentials(*l.ssl);
 400                                 }
 401
 402                                 builder.AddListeningPort(addr, a);
 403                                 INFO("grpc: Listening on %s%s", addr.c_str(), use_ssl.c_str());
 404                         }
 405                 }
 406
 407                 builder.RegisterService(&collectd_service_);
 408
 409                 server_ = builder.BuildAndStart();
 410         } /* Start() */
 411
 412         void Shutdown()
 413         {
 414                 server_->Shutdown();
 415         } /* Shutdown() */
 416
 417 private:
 418         CollectdImpl collectd_service_;
 419
 420         std::unique_ptr<grpc::Server> server_;
 421 }; /* class CollectdServer */
 422
 423 static CollectdServer *server = nullptr;
 424
 425 /*
 426  * collectd plugin interface
 427  */
 428 extern "C" {
 429         static int c_grpc_config_listen(oconfig_item_t *ci)
 430         {
 431                 if ((ci->values_num != 2)
 432                                 || (ci->values[0].type != OCONFIG_TYPE_STRING)
 433                                 || (ci->values[1].type != OCONFIG_TYPE_STRING)) {
 434                         ERROR("grpc: The `%s` config option needs exactly "
 435                                         "two string argument (address and port).", ci->key);
 436                         return -1;
 437                 }
 438
 439                 auto listener = Listener();
 440                 listener.addr = grpc::string(ci->values[0].value.string);
 441                 listener.port = grpc::string(ci->values[1].value.string);
 442                 listener.ssl = nullptr;
 443
 444                 auto ssl_opts = new(grpc::SslServerCredentialsOptions);
 445                 grpc::SslServerCredentialsOptions::PemKeyCertPair pkcp = {};
 446                 bool use_ssl = false;
 447
 448                 for (int i = 0; i < ci->children_num; i++) {
 449                         oconfig_item_t *child = ci->children + i;
 450
 451                         if (!strcasecmp("EnableSSL", child->key)) {
 452                                 if (cf_util_get_boolean(child, &use_ssl)) {
 453                                         ERROR("grpc: Option `%s` expects a boolean value",
 454                                                         child->key);
 455                                         return -1;
 456                                 }
 457                         }
 458                         else if (!strcasecmp("SSLRootCerts", child->key)) {
 459                                 char *certs = NULL;
 460                                 if (cf_util_get_string(child, &certs)) {
 461                                         ERROR("grpc: Option `%s` expects a string value",
 462                                                         child->key);
 463                                         return -1;
 464                                 }
 465                                 ssl_opts->pem_root_certs = read_file(certs);
 466                         }
 467                         else if (!strcasecmp("SSLServerKey", child->key)) {
 468                                 char *key = NULL;
 469                                 if (cf_util_get_string(child, &key)) {
 470                                         ERROR("grpc: Option `%s` expects a string value",
 471                                                         child->key);
 472                                         return -1;
 473                                 }
 474                                 pkcp.private_key = read_file(key);
 475                         }
 476                         else if (!strcasecmp("SSLServerCert", child->key)) {
 477                                 char *cert = NULL;
 478                                 if (cf_util_get_string(child, &cert)) {
 479                                         ERROR("grpc: Option `%s` expects a string value",
 480                                                         child->key);
 481                                         return -1;
 482                                 }
 483                                 pkcp.cert_chain = read_file(cert);
 484                         }
 485                         else {
 486                                 WARNING("grpc: Option `%s` not allowed in <%s> block.",
 487                                                 child->key, ci->key);
 488                         }
 489                 }
 490
 491                 ssl_opts->pem_key_cert_pairs.push_back(pkcp);
 492                 if (use_ssl)
 493                         listener.ssl = ssl_opts;
 494                 else
 495                         delete(ssl_opts);
 496
 497                 listeners.push_back(listener);
 498                 return 0;
 499         } /* c_grpc_config_listen() */
 500
 501         static int c_grpc_config(oconfig_item_t *ci)
 502         {
 503                 int i;
 504
 505                 for (i = 0; i < ci->children_num; i++) {
 506                         oconfig_item_t *child = ci->children + i;
 507
 508                         if (!strcasecmp("Listen", child->key)) {
 509                                 if (c_grpc_config_listen(child))
 510                                         return -1;
 511                         }
 512                         else {
 513                                 WARNING("grpc: Option `%s` not allowed here.", child->key);
 514                         }
 515                 }
 516
 517                 return 0;
 518         } /* c_grpc_config() */
 519
 520         static int c_grpc_init(void)
 521         {
 522                 server = new CollectdServer();
 523                 if (!server) {
 524                         ERROR("grpc: Failed to create server");
 525                         return -1;
 526                 }
 527
 528                 server->Start();
 529                 return 0;
 530         } /* c_grpc_init() */
 531
 532         static int c_grpc_shutdown(void)
 533         {
 534                 if (!server)
 535                         return 0;
 536
 537                 server->Shutdown();
 538
 539                 delete server;
 540                 server = nullptr;
 541
 542                 return 0;
 543         } /* c_grpc_shutdown() */
 544
 545         void module_register(void)
 546         {
 547                 plugin_register_complex_config("grpc", c_grpc_config);
 548                 plugin_register_init("grpc", c_grpc_init);
 549                 plugin_register_shutdown("grpc", c_grpc_shutdown);
 550         } /* module_register() */
 551 } /* extern "C" */
 552
 553 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */