collectagent.cpp

//================================================================================
// Name        : collectagent.cpp
// Author      : Axel Auweter
// Copyright   : Leibniz Supercomputing Centre
// Description : Main code of the CollectAgent
//================================================================================

//================================================================================
// This file is part of DCDB (DataCenter DataBase)
// Copyright (C) 2011-2016 Leibniz Supercomputing Centre
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//================================================================================

#include <boost/network/protocol/http/server.hpp>
#include <boost/network/utils/thread_pool.hpp>
#include <boost/network/uri.hpp>
#include <iostream>
#include <cstdlib>
#include <signal.h>
#include <unistd.h>
#include <string>

#include <boost/date_time/posix_time/posix_time.hpp>

#include <dcdb/connection.h>
#include <dcdb/sensordatastore.h>
#include <dcdb/sensorconfig.h>

#include "simplemqttserver.h"
#include "messaging.h"
#include "abrt.h"
#include "dcdbdaemon.h"

#include "sensorcache.h"

#define __STDC_FORMAT_MACROS
#include <inttypes.h>

using namespace std;

#define LISTENHOST "localhost"
#define LISTENPORT "1883"
#define CASSANDRAHOST "127.0.0.1"
#define CASSANDRAPORT "9042"
#define RESTAPIHOST "0.0.0.0"
#define RESTAPIPORT "8080"
#define TTL "0"

int keepRunning;
bool statistics;
uint64_t msgCtr;
uint64_t pmsgCtr;
DCDB::Connection* dcdbConn;
DCDB::SensorDataStore *mySensorDataStore;
DCDB::SensorConfig *mySensorConfig;
DCDB::SensorCache mySensorCache;
DCDB::SCError err;

/* Normal termination (SIGINT, CTRL+C) */
void sigHandler(int sig)
{
  keepRunning = 0;
}

/* Crash */
void abrtHandler(int sig)
{
  abrt(EXIT_FAILURE, SIGNAL);
}

struct httpHandler_t;
typedef boost::network::http::server<httpHandler_t> httpServer_t;
struct httpHandler_t {
  void operator()(httpServer_t::request const &request, httpServer_t::connection_ptr connection) {
    httpServer_t::string_type ip = source(request);
    std::ostringstream data;
    static httpServer_t::response_header headers[] = { { "Connection", "close" }, { "Content-Type", "text/plain" } };

    //try getting the latest value 
    try {
      boost::network::uri::uri uri("http://localhost"+request.destination);
      std::map<std::string, std::string> queries;
      boost::network::uri::query_map(uri, queries);
      int avg = atoi(queries.find("avg")->second.c_str());

      uint64_t val = mySensorCache.getSensor(uri.path(), (uint64_t) avg);

      data << val << "\n";
      //data << "Sid : " << sid.toString() << ", Value: " << val << "." << std::endl;

      connection->set_status(httpServer_t::connection::ok);
      connection->set_headers(boost::make_iterator_range(headers, headers + 2));
      connection->write(data.str());

    }

    catch (const std::invalid_argument& e) {
      connection->set_status(httpServer_t::connection::not_found);
      connection->set_headers(boost::make_iterator_range(headers, headers + 2));
      connection->write("Error: Sensor id not found.\n");
    } catch (const std::out_of_range &e) {
      connection->set_status(httpServer_t::connection::no_content);
      connection->set_headers(boost::make_iterator_range(headers, headers + 2));
      connection->write("Error: Sensor unavailable.\n");
    } catch (const std::exception& e) {
      connection->set_status(httpServer_t::connection::internal_server_error);
      connection->set_headers(boost::make_iterator_range(headers, headers + 2));
      connection->write("Server error.\n");
    }

  }
};


int mqttCallback(SimpleMQTTMessage *msg)
{
  /*
   * Increment the msgCtr/vmsgCtr for statistics.
   */
  msgCtr++;
  if (msg->isPublish())
    pmsgCtr++;

  uint64_t len;
  /*
   * Decode the message and put into the database.
   */
  if (msg->isPublish()) {
      const char *topic = msg->getTopic().c_str();
      // We check whether the topic includes the \DCDB_MAP\ keyword, indicating that the payload will contain the
      // sensor's name. In that case, we set the mappingMessage flag to true, and filter the keyword out of the prefix
      // We use strncmp as it is the most efficient way to do it
      if (strlen(topic) > DCDB_MAP_LEN && strncmp(topic, DCDB_MAP, DCDB_MAP_LEN) == 0) {
          if ((len = msg->getPayloadLength()) == 0) {
              cout << "Empty topic-to-name mapping message received\n";
              return 1;
          }

          string sensorName((char *) msg->getPayload(), len);
          err = mySensorConfig->publishSensor(sensorName.c_str(), topic + DCDB_MAP_LEN);

          // PublishSensor does most of the error checking for us
          switch (err) {
              case DCDB::SC_INVALIDPATTERN:
                  std::cout << "Invalid sensor topic : " << msg->getTopic() << std::endl;
                  return 1;
              case DCDB::SC_INVALIDPUBLICNAME:
                  std::cout << "Invalid sensor public name: " << sensorName << std::endl;
                  return 1;
              case DCDB::SC_INVALIDSESSION:
                  std::cout << "Cannot reach sensor data store." << std::endl;
                  return 1;
              default:
                  break;
          }
      } else {
          mqttPayload buf, *payload;

          len = msg->getPayloadLength();
          //In the 64 bit message case, the collect agent provides a timestamp
          if (len == sizeof(uint64_t)) {
              payload = &buf;
              payload->value = *((uint64_t *) msg->getPayload());
              payload->timestamp = Messaging::calculateTimestamp();
              len = sizeof(uint64_t) * 2;
          }
              //...otherwise it just retrieves it from the MQTT message payload.
          else if ((len % sizeof(mqttPayload) == 0) && (len > 0)) {
              payload = (mqttPayload *) msg->getPayload();
          }
              //...otherwise this message is malformed -> ignore...
          else {
              cout << "Message malformed\n";
              return 1;
          }

          /*
           * Check if we can decode the message topic
           * into a valid SensorId. If successful, store
           * the record in the database.
           */
          DCDB::SensorId sid;
          if (sid.mqttTopicConvert(msg->getTopic())) {
#if 0
              cout << "Topic decode successful:" << endl
                  << "  Raw:            " << hex << setw(16) << setfill('0') << sid.getRaw()[0] << hex << setw(16) << setfill('0') << sid.getRaw()[1] << endl
                  << "  DeviceLocation: " << hex << setw(16) << setfill('0') << sid.getDeviceLocation() << endl
                  << "  device_id:      " << hex << setw(8) << setfill('0') << sid.getDeviceSensorId().device_id << endl
                  << "  sensor_number:  " << hex << setw(4) << setfill('0') << sid.getDeviceSensorId().sensor_number << endl << dec;

              cout << "Payload ("  << len/sizeof(mqttPayload) << " messages):"<< endl;
              for (uint64_t i=0; i<len/sizeof(mqttPayload); i++) {
                cout << "  " << i << ": ts=" << payload[i].timestamp << " val=" << payload[i].value << endl;
              }
              cout << endl;
#endif
              for (uint64_t i = 0; i < len / sizeof(mqttPayload); i++) {
                  mySensorDataStore->insert(&sid, payload[i].timestamp, payload[i].value);
                  mySensorCache.storeSensor(sid, payload[i].timestamp, payload[i].value);

              }
              //mySensorCache.dump();
          }
#if 1
          else {
              cout << "Wrong topic format: " << msg->getTopic() << "\n";
              return 1;
          }
#endif
      }
  }
  return 0;
}




/*
 * Print usage information
 */
void usage() {
  /*
             1         2         3         4         5         6         7         8
   012345678901234567890123456789012345678901234567890123456789012345678901234567890
   */
  cout << "Usage:" << endl;
  cout << "  collectagent [-m<host>] [-r<host>] [-c<host>] [-u<username>] [-p<password>] [-t<ttl>] [-d] [-s]" << endl;
  cout << "  collectagent -h" << endl;
  cout << endl;
  
  cout << "Options:" << endl;
  cout << "  -m<host>      MQTT listen address     [default: " << LISTENHOST << ":" << LISTENPORT << "]" << endl;
  cout << "  -r<host>      REST API listen address [default: " << RESTAPIHOST << ":" << RESTAPIPORT << "]" << endl;
  cout << "  -c<host>      Cassandra host          [default: " << CASSANDRAHOST << ":" << CASSANDRAPORT << "]" << endl;
  cout << "  -u<username>  Cassandra username      [default: none]" << endl;
  cout << "  -p<password>  Cassandra password      [default: none]" << endl;
  cout << "  -t<ttl>       Cassandra insert TTL    [default: " << TTL << "]" << endl;
  cout << endl;
  cout << "  -d            Daemonize" << endl;
  cout << "  -s            Print message statistics" << endl;
  cout << "  -h            This help page" << endl;
  cout << endl;
}

int main(int argc, char* const argv[]) {

  try{
      /*
       * Catch SIGINT signals to allow for proper server shutdowns.
       */
      signal(SIGINT, sigHandler);

      /*
       * Catch critical signals to allow for backtraces
       */
      signal(SIGABRT, abrtHandler);
      signal(SIGSEGV, abrtHandler);
      signal(SIGTERM, abrtHandler);

      /* Parse command line */
      int ret;
      std::string listenHost, cassandraHost, restApiHost, ttl;
      std::string cassandraUser, cassandraPassword;
      std::string listenPort, cassandraPort, restApiPort;
    
      listenHost = LISTENHOST;
      cassandraHost = CASSANDRAHOST;
      restApiHost = RESTAPIHOST;
      ttl = "0";
      statistics = false;
    
    while ((ret=getopt(argc, argv, "m:r:c:u:p:t:dDsh"))!=-1) {
          switch(ret) {
              case 'm':
                  listenHost = optarg;
                  break;
              case 'r':
                  restApiHost = optarg;
                  break;
              case 'c':
                  cassandraHost = optarg;
                  break;
              case 'u':
                  cassandraUser = optarg;
                  break;
              case 'p': {
                  cassandraPassword = optarg;
                  size_t pwdLen = strlen(optarg);
                  memset(optarg, 'x', (pwdLen >= 3) ? 3 : pwdLen);
                  if (pwdLen > 3) {
                      memset(optarg+3, 0, pwdLen-3);
                  }
                  break;
              }
              case 't':
                  ttl = optarg;
                  break;
              case 'd':
              case 'D':
                  dcdbdaemon();
                  break;
              case 's':
                  statistics = true;
                  break;
              case 'h':
              default:
                  usage();
                  exit(EXIT_FAILURE);
          }
      }

      /*
       * Parse hostnames for port specifications
       */
      size_t pos = listenHost.find(":");
      if (pos != string::npos) {
        listenPort = listenHost.substr(pos+1);
        listenHost.erase(pos);
      } else {
        listenPort = LISTENPORT;
      }
      pos = cassandraHost.find(":");
      if (pos != string::npos) {
        cassandraPort = cassandraHost.substr(pos+1);
        cassandraHost.erase(pos);
      } else {
        cassandraPort = CASSANDRAPORT;
      }
      pos = restApiHost.find(":");
      if (pos != string::npos) {
        restApiPort = restApiHost.substr(pos+1);
        restApiHost.erase(pos);
      } else {
        restApiPort = RESTAPIPORT;
      }


      /*
       * Allocate and initialize connection to Cassandra.
       */
      dcdbConn = new DCDB::Connection(cassandraHost, atoi(cassandraPort.c_str()), cassandraUser, cassandraPassword);

      if (!dcdbConn->connect()) {
          std::cout << "Cannot connect to Cassandra!" << std::endl;
          exit(EXIT_FAILURE);
      }

      /*
       * Legacy behavior: Initialize the DCDB schema in Cassandra.
       */
      dcdbConn->initSchema();

      /*
       * Allocate the SensorDataStore.
       */
      mySensorDataStore = new DCDB::SensorDataStore(dcdbConn);
      mySensorConfig = new DCDB::SensorConfig(dcdbConn);

      /*
       * Set TTL for data store inserts if TTL > 0.
       */
      uint64_t ttlInt;
      std::istringstream ttlParser(ttl);
      if (!(ttlParser >> ttlInt)) {
          std::cout << "Invalid TTL!" << std::endl;
          exit(EXIT_FAILURE);
      }
      if (ttlInt) {
        mySensorDataStore->setTTL(ttlInt);
      }

      /*
       * Start the MQTT Message Server.
       */
      SimpleMQTTServer ms(listenHost, listenPort);
      
      ms.setMessageCallback(mqttCallback);
      ms.start();

      cout << "MQTT Server running..." << std::endl;
      
      /*
       * Start the HTTP Server for the REST API
       */
      std::thread httpThread;
      httpHandler_t httpHandler;
      httpServer_t::options httpOptions(httpHandler);

      httpOptions.reuse_address(true);
      httpOptions.thread_pool(std::make_shared<boost::network::utils::thread_pool>());
      httpServer_t httpServer(httpOptions.address(restApiHost).port(restApiPort));
      httpThread = std::thread([&httpServer] { httpServer.run(); });

      cout << "HTTP Server running..." << std::endl;

      /*
       * Run (hopefully) forever...
       */
      keepRunning = 1;
      timeval start, end;
      double elapsed;
      
      cout << "Collect Agent running..." << std::endl;

      while(keepRunning) {
          gettimeofday(&start, NULL);
          sleep(60);
          /* not really thread safe but will do the job */
          gettimeofday(&end, NULL);
          elapsed = (end.tv_sec - start.tv_sec) * 1000.0;
          elapsed += (end.tv_usec - start.tv_usec) / 1000.0;
          float publish = msgCtr?(pmsgCtr*100.0)/msgCtr:0;
          if (statistics) {
              cout << "Message rate: " << (msgCtr/elapsed)*1000.0 << " messages/second (" << publish << "% PUBLISH)\n";
          }
          msgCtr = 0;
          pmsgCtr = 0;
      }

      cout << "Stopping...\n";

      ms.stop();
      cout << "MQTT Server stopped..." << std::endl;
      httpServer.stop();
      httpThread.join();
      cout << "HTTP Server stopped..." << std::endl;
      delete mySensorDataStore;
      delete mySensorConfig;
      dcdbConn->disconnect();
      delete dcdbConn;
      cout << "Collect Agent closed. Bye bye..." << std::endl;
  }
  catch (const exception& e) {
      cout << "Exception: " << e.what() << "\n";
      abrt(EXIT_FAILURE, INTERR);
  }

  return EXIT_SUCCESS;
}