src/charging-station/ChargingStation.js

   1 const Configuration = require('../utils/Configuration');
   2 const logger = require('../utils/Logger');
   3 const WebSocket = require('ws');
   4 const Constants = require('../utils/Constants');
   5 const Utils = require('../utils/Utils');
   6 const OCPPError = require('./OcppError');
   7 const {v4: uuid} = require('uuid');
   8 const AutomaticTransactionGenerator = require('./AutomaticTransactionGenerator');
   9 const Statistics = require('../utils/Statistics');
  10 const fs = require('fs');
  11 const {performance, PerformanceObserver} = require('perf_hooks');
  12
  13 class ChargingStation {
  14   constructor(index, stationTemplateFile) {
  15     this._index = index;
  16     this._stationTemplateFile = stationTemplateFile;
  17     this._initialize();
  18
  19     this._autoReconnectRetryCount = 0;
  20     this._autoReconnectMaxRetries = Configuration.getAutoReconnectMaxRetries(); // -1 for unlimited
  21     this._autoReconnectTimeout = Configuration.getAutoReconnectTimeout() * 1000; // ms, zero for disabling
  22
  23     this._requests = {};
  24     this._messageQueue = [];
  25
  26     this._isSocketRestart = false;
  27   }
  28
  29   _initialize() {
  30     this._stationInfo = this._buildStationInfo();
  31     this._bootNotificationMessage = {
  32       chargePointModel: this._stationInfo.chargePointModel,
  33       chargePointVendor: this._stationInfo.chargePointVendor,
  34     };
  35     this._configuration = this._getConfiguration();
  36     this._authorizedTags = this._getAuthorizedTags();
  37     this._supervisionUrl = this._getSupervisionURL();
  38     this._statistics = new Statistics(this._stationInfo.name);
  39     this._performanceObserver = new PerformanceObserver((list) => {
  40       const entry = list.getEntries()[0];
  41       this._statistics.logPerformance(entry, 'ChargingStation');
  42       this._performanceObserver.disconnect();
  43     });
  44   }
  45
  46   _basicFormatLog() {
  47     return Utils.basicFormatLog(` ${this._stationInfo.name}:`);
  48   }
  49
  50   _getConfiguration() {
  51     return this._stationInfo.Configuration ? this._stationInfo.Configuration : {};
  52   }
  53
  54   _getAuthorizationFile() {
  55     return this._stationInfo.authorizationFile ? this._stationInfo.authorizationFile : '';
  56   }
  57
  58   _getAuthorizedTags() {
  59     let authorizedTags = [];
  60     const authorizationFile = this._getAuthorizationFile();
  61     if (authorizationFile) {
  62       try {
  63         // Load authorization file
  64         const fileDescriptor = fs.openSync(authorizationFile, 'r');
  65         authorizedTags = JSON.parse(fs.readFileSync(fileDescriptor, 'utf8'));
  66         fs.closeSync(fileDescriptor);
  67       } catch (error) {
  68         logger.error(this._basicFormatLog() + ' Authorization file loading error: ' + error);
  69       }
  70     } else {
  71       logger.info(this._basicFormatLog() + ' No authorization file given in template file ' + this._stationTemplateFile);
  72     }
  73     return authorizedTags;
  74   }
  75
  76   _startAuthorizationFileMonitoring() {
  77     // eslint-disable-next-line no-unused-vars
  78     fs.watchFile(this._getAuthorizationFile(), (current, previous) => {
  79       try {
  80         logger.debug(this._basicFormatLog() + ' Authorization file ' + this._getAuthorizationFile() + ' have changed, reload');
  81         // Initialize _authorizedTags
  82         this._authorizedTags = this._getAuthorizedTags();
  83       } catch (error) {
  84         logger.error(this._basicFormatLog() + ' Authorization file monitoring error: ' + error);
  85       }
  86     });
  87   }
  88
  89   _startStationTemplateFileMonitoring() {
  90     // eslint-disable-next-line no-unused-vars
  91     fs.watchFile(this._stationTemplateFile, (current, previous) => {
  92       try {
  93         logger.debug(this._basicFormatLog() + ' Template file ' + this._stationTemplateFile + ' have changed, reload');
  94         // Initialize
  95         this._initialize();
  96       } catch (error) {
  97         logger.error(this._basicFormatLog() + ' Charging station template file monitoring error: ' + error);
  98       }
  99     });
 100   }
 101
 102   _getSupervisionURL() {
 103     const supervisionUrls = Utils.cloneJSonDocument(this._stationInfo.supervisionURL ? this._stationInfo.supervisionURL : Configuration.getSupervisionURLs());
 104     let indexUrl = 0;
 105     if (Array.isArray(supervisionUrls)) {
 106       if (Configuration.getDistributeStationToTenantEqually()) {
 107         indexUrl = this._index % supervisionUrls.length;
 108       } else {
 109         // Get a random url
 110         indexUrl = Math.floor(Math.random() * supervisionUrls.length);
 111       }
 112       return supervisionUrls[indexUrl];
 113     }
 114     return supervisionUrls;
 115   }
 116
 117   _getStationName(stationTemplate) {
 118     return stationTemplate.fixedName ? stationTemplate.baseName : stationTemplate.baseName + '-' + ('000000000' + this._index).substr(('000000000' + this._index).length - 4);
 119   }
 120
 121   _getAuthorizeRemoteTxRequests() {
 122     const authorizeRemoteTxRequests = this._configuration.configurationKey.find((configElement) => configElement.key === 'AuthorizeRemoteTxRequests');
 123     return authorizeRemoteTxRequests ? Utils.convertToBoolean(authorizeRemoteTxRequests.value) : false;
 124   }
 125
 126   _getLocalAuthListEnabled() {
 127     const localAuthListEnabled = this._configuration.configurationKey.find((configElement) => configElement.key === 'LocalAuthListEnabled');
 128     return localAuthListEnabled ? Utils.convertToBoolean(localAuthListEnabled.value) : false;
 129   }
 130
 131   _buildStationInfo() {
 132     let stationTemplateFromFile;
 133     try {
 134       // Load template file
 135       const fileDescriptor = fs.openSync(this._stationTemplateFile, 'r');
 136       stationTemplateFromFile = JSON.parse(fs.readFileSync(fileDescriptor, 'utf8'));
 137       fs.closeSync(fileDescriptor);
 138     } catch (error) {
 139       logger.error(this._basicFormatLog() + ' Template file loading error: ' + error);
 140     }
 141     const stationTemplate = stationTemplateFromFile || {};
 142     if (Array.isArray(stationTemplateFromFile.power)) {
 143       stationTemplate.maxPower = stationTemplateFromFile.power[Math.floor(Math.random() * stationTemplateFromFile.power.length)];
 144     } else {
 145       stationTemplate.maxPower = stationTemplateFromFile.power;
 146     }
 147     stationTemplate.name = this._getStationName(stationTemplateFromFile);
 148     return stationTemplate;
 149   }
 150
 151   async start() {
 152     logger.info(this._basicFormatLog() + ' Will communicate with ' + this._supervisionUrl);
 153     // Monitor authorization file
 154     this._startAuthorizationFileMonitoring();
 155     // Monitor station template file
 156     this._startStationTemplateFileMonitoring();
 157     this._url = this._supervisionUrl + '/' + this._stationInfo.name;
 158     this._wsConnection = new WebSocket(this._url, 'ocpp1.6');
 159     // Handle Socket incoming messages
 160     this._wsConnection.on('message', this.onMessage.bind(this));
 161     // Handle Socket error
 162     this._wsConnection.on('error', this.onError.bind(this));
 163     // Handle Socket close
 164     this._wsConnection.on('close', this.onClose.bind(this));
 165     // Handle Socket opening connection
 166     this._wsConnection.on('open', this.onOpen.bind(this));
 167     // Handle Socket ping
 168     this._wsConnection.on('ping', this.onPing.bind(this));
 169   }
 170
 171   onOpen() {
 172     logger.info(`${this._basicFormatLog()} Is connected to server through ${this._url}`);
 173     if (this._isSocketRestart) {
 174       this.basicStartMessageSequence();
 175       if (this._messageQueue.length > 0) {
 176         this._messageQueue.forEach((message) => {
 177           if (this._wsConnection.readyState === WebSocket.OPEN) {
 178             this._wsConnection.send(message);
 179           }
 180         });
 181       }
 182     } else {
 183       // At first start, send BootNotification
 184       try {
 185         this.sendMessage(uuid(), this._bootNotificationMessage, Constants.OCPP_JSON_CALL_MESSAGE, 'BootNotification');
 186       } catch (error) {
 187         logger.error(this._basicFormatLog() + ' Send boot notification error: ' + error);
 188       }
 189     }
 190     this._autoReconnectRetryCount = 0;
 191     this._isSocketRestart = false;
 192   }
 193
 194   onError(error) {
 195     switch (error) {
 196       case 'ECONNREFUSED':
 197         this._isSocketRestart = true;
 198         this._reconnect(error);
 199         break;
 200       default:
 201         logger.error(this._basicFormatLog() + ' Socket error: ' + error);
 202         break;
 203     }
 204   }
 205
 206   onClose(error) {
 207     switch (error) {
 208       case 1000: // Normal close
 209       case 1005:
 210         logger.info(this._basicFormatLog() + ' Socket normally closed ' + error);
 211         this._autoReconnectRetryCount = 0;
 212         break;
 213       default: // Abnormal close
 214         this._isSocketRestart = true;
 215         this._reconnect(error);
 216         break;
 217     }
 218   }
 219
 220   onPing() {
 221     logger.info(this._basicFormatLog() + ' Has received a WS ping (rfc6455) from the server');
 222   }
 223
 224   async onMessage(message) {
 225     let [messageType, messageId, commandName, commandPayload, errorDetails] = [0, '', Constants.ENTITY_CHARGING_STATION, '', ''];
 226     try {
 227       // Parse the message
 228       [messageType, messageId, commandName, commandPayload, errorDetails] = JSON.parse(message);
 229
 230       // Check the Type of message
 231       switch (messageType) {
 232         // Incoming Message
 233         case Constants.OCPP_JSON_CALL_MESSAGE:
 234           // Process the call
 235           this._statistics.addMessage(commandName);
 236           await this.handleRequest(messageId, commandName, commandPayload);
 237           break;
 238         // Outcome Message
 239         case Constants.OCPP_JSON_CALL_RESULT_MESSAGE:
 240           // Respond
 241           // eslint-disable-next-line no-case-declarations
 242           let responseCallback; let requestPayload;
 243           if (Utils.isIterable(this._requests[messageId])) {
 244             [responseCallback, , requestPayload] = this._requests[messageId];
 245           } else {
 246             throw new Error(`Response request for unknown message id ${messageId} is not iterable`);
 247           }
 248           if (!responseCallback) {
 249             // Error
 250             throw new Error(`Response for unknown message id ${messageId}`);
 251           }
 252           delete this._requests[messageId];
 253           // this._statistics.addMessage(commandName)
 254           responseCallback(commandName, requestPayload);
 255           break;
 256         // Error Message
 257         case Constants.OCPP_JSON_CALL_ERROR_MESSAGE:
 258           if (!this._requests[messageId]) {
 259             // Error
 260             throw new Error(`Error for unknown message id ${messageId}`);
 261           }
 262           // eslint-disable-next-line no-case-declarations
 263           let rejectCallback;
 264           if (Utils.isIterable(this._requests[messageId])) {
 265             [, rejectCallback] = this._requests[messageId];
 266           } else {
 267             throw new Error(`Error request for unknown message id ${messageId} is not iterable`);
 268           }
 269           delete this._requests[messageId];
 270           rejectCallback(new OCPPError(commandName, commandPayload, errorDetails));
 271           break;
 272         // Error
 273         default:
 274           throw new Error(`Wrong message type ${messageType}`);
 275       }
 276     } catch (error) {
 277       // Log
 278       logger.error('%s Incoming message %j processing error %s on request content %s', this._basicFormatLog(), message, error, this._requests[messageId]);
 279       // Send error
 280       // await this.sendError(messageId, error);
 281     }
 282   }
 283
 284   _reconnect(error) {
 285     logger.error(this._basicFormatLog() + ' Socket: abnormally closed', error);
 286     // Stop heartbeat interval
 287     if (this._heartbeatSetInterval) {
 288       clearInterval(this._heartbeatSetInterval);
 289       this._heartbeatSetInterval = null;
 290     }
 291     // Stop the ATG
 292     if (this._stationInfo.AutomaticTransactionGenerator.enable && this._automaticTransactionGeneration &&
 293       !this._automaticTransactionGeneration._timeToStop) {
 294       this._automaticTransactionGeneration.stop();
 295     }
 296     if (this._autoReconnectTimeout !== 0 &&
 297       (this._autoReconnectRetryCount < this._autoReconnectMaxRetries || this._autoReconnectMaxRetries === -1)) {
 298       logger.error(`${this._basicFormatLog()} Socket: connection retry with timeout ${this._autoReconnectTimeout}ms`);
 299       this._autoReconnectRetryCount++;
 300       setTimeout(() => {
 301         logger.error(this._basicFormatLog() + ' Socket: reconnecting try #' + this._autoReconnectRetryCount);
 302         this.start();
 303       }, this._autoReconnectTimeout);
 304     } else if (this._autoReconnectTimeout !== 0 || this._autoReconnectMaxRetries !== -1) {
 305       logger.error(`${this._basicFormatLog()} Socket: max retries reached (${this._autoReconnectRetryCount}) or retry disabled (${this._autoReconnectTimeout})`);
 306     }
 307   }
 308
 309   send(command, messageType = Constants.OCPP_JSON_CALL_MESSAGE) {
 310     // Send Message
 311     return this.sendMessage(uuid(), command, messageType);
 312   }
 313
 314   sendError(messageId, err) {
 315     // Check exception: only OCPP error are accepted
 316     const error = (err instanceof OCPPError ? err : new OCPPError(Constants.OCPP_ERROR_INTERNAL_ERROR, err.message));
 317     // Send error
 318     return this.sendMessage(messageId, error, Constants.OCPP_JSON_CALL_ERROR_MESSAGE);
 319   }
 320
 321   sendMessage(messageId, command, messageType = Constants.OCPP_JSON_CALL_RESULT_MESSAGE, commandName = '') {
 322     // Send a message through wsConnection
 323     const self = this;
 324     // Create a promise
 325     return new Promise((resolve, reject) => {
 326       let messageToSend;
 327       // Type of message
 328       switch (messageType) {
 329         // Request
 330         case Constants.OCPP_JSON_CALL_MESSAGE:
 331           this._statistics.addMessage(commandName);
 332           // Build request
 333           this._requests[messageId] = [responseCallback, rejectCallback, command];
 334           messageToSend = JSON.stringify([messageType, messageId, commandName, command]);
 335           break;
 336         // Response
 337         case Constants.OCPP_JSON_CALL_RESULT_MESSAGE:
 338           // Build response
 339           messageToSend = JSON.stringify([messageType, messageId, command]);
 340           break;
 341         // Error Message
 342         case Constants.OCPP_JSON_CALL_ERROR_MESSAGE:
 343           // Build Message
 344           this._statistics.addMessage(`Error ${command.code}`);
 345           messageToSend = JSON.stringify([messageType, messageId, command.code ? command.code : Constants.OCPP_ERROR_GENERIC_ERROR, command.message ? command.message : '', command.details ? command.details : {}]);
 346           break;
 347       }
 348       // Check if wsConnection is ready
 349       if (this._wsConnection.readyState === WebSocket.OPEN) {
 350         // Yes: Send Message
 351         this._wsConnection.send(messageToSend);
 352       } else {
 353         // Buffer message until connection is back
 354         this._messageQueue.push(messageToSend);
 355       }
 356       // Request?
 357       if (messageType !== Constants.OCPP_JSON_CALL_MESSAGE) {
 358         // Yes: send Ok
 359         resolve();
 360       } else if (this._wsConnection.readyState === WebSocket.OPEN) {
 361         // Send timeout in case connection is open otherwise wait for ever
 362         // FIXME: Handle message on timeout
 363         setTimeout(() => rejectCallback(`Timeout for message ${messageId}`), Constants.OCPP_SOCKET_TIMEOUT);
 364       }
 365
 366       // Function that will receive the request's response
 367       function responseCallback(payload, requestPayload) {
 368         self._statistics.addMessage(commandName, true);
 369         const responseCallbackFn = 'handleResponse' + commandName;
 370         if (typeof self[responseCallbackFn] === 'function') {
 371           self[responseCallbackFn](payload, requestPayload, self);
 372         } else {
 373           logger.debug(self._basicFormatLog() + ' Trying to call an undefined callback function: ' + responseCallbackFn);
 374         }
 375         // Send the response
 376         resolve(payload);
 377       }
 378
 379       // Function that will receive the request's rejection
 380       function rejectCallback(reason) {
 381         // Build Exception
 382         // eslint-disable-next-line no-empty-function
 383         self._requests[messageId] = [() => { }, () => { }, '']; // Properly format the request
 384         const error = reason instanceof OCPPError ? reason : new Error(reason);
 385         // Send error
 386         reject(error);
 387       }
 388     });
 389   }
 390
 391   handleResponseBootNotification(payload) {
 392     if (payload.status === 'Accepted') {
 393       this._heartbeatInterval = payload.interval * 1000;
 394       this.basicStartMessageSequence();
 395     } else {
 396       logger.info(this._basicFormatLog() + ' Boot Notification rejected');
 397     }
 398   }
 399
 400   async basicStartMessageSequence() {
 401     this._startHeartbeat(this);
 402     // build connectors
 403     if (!this._connectors) {
 404       this._connectors = {};
 405       const connectorsConfig = Utils.cloneJSonDocument(this._stationInfo.Connectors);
 406       // determine number of customized connectors
 407       let lastConnector;
 408       for (lastConnector in connectorsConfig) {
 409         // add connector 0, OCPP specification violation that for example KEBA have
 410         if (Utils.convertToInt(lastConnector) === 0 && this._stationInfo.useConnectorId0) {
 411           this._connectors[lastConnector] = connectorsConfig[lastConnector];
 412         }
 413       }
 414       let maxConnectors = 0;
 415       if (Array.isArray(this._stationInfo.numberOfConnectors)) {
 416         // generate some connectors
 417         maxConnectors = this._stationInfo.numberOfConnectors[(this._index - 1) % this._stationInfo.numberOfConnectors.length];
 418       } else {
 419         maxConnectors = this._stationInfo.numberOfConnectors;
 420       }
 421       // generate all connectors
 422       for (let index = 1; index <= maxConnectors; index++) {
 423         const randConnectorID = this._stationInfo.randomConnectors ? Utils.getRandomInt(maxConnectors, 1) : index;
 424         this._connectors[index] = connectorsConfig[randConnectorID];
 425       }
 426     }
 427
 428     for (const connector in this._connectors) {
 429       if (!this._connectors[connector].transactionStarted) {
 430         if (this._connectors[connector].bootStatus) {
 431           setTimeout(() => this.sendStatusNotification(connector, this._connectors[connector].bootStatus), Constants.STATUS_NOTIFICATION_TIMEOUT);
 432         } else {
 433           setTimeout(() => this.sendStatusNotification(connector, 'Available'), Constants.STATUS_NOTIFICATION_TIMEOUT);
 434         }
 435       } else {
 436         setTimeout(() => this.sendStatusNotification(connector, 'Charging'), Constants.STATUS_NOTIFICATION_TIMEOUT);
 437       }
 438     }
 439
 440     if (this._stationInfo.AutomaticTransactionGenerator.enable) {
 441       if (!this._automaticTransactionGeneration) {
 442         this._automaticTransactionGeneration = new AutomaticTransactionGenerator(this);
 443       }
 444       this._automaticTransactionGeneration.start();
 445     }
 446     this._statistics.start();
 447   }
 448
 449   handleResponseStartTransaction(payload, requestPayload) {
 450     // Reset connector transaction related attributes
 451     this._connectors[requestPayload.connectorId].transactionStarted = false;
 452     this._connectors[requestPayload.connectorId].idTag = requestPayload.idTag;
 453
 454     if (payload.idTagInfo.status === 'Accepted') {
 455       for (const connector in this._connectors) {
 456         if (Utils.convertToInt(connector) === Utils.convertToInt(requestPayload.connectorId)) {
 457           this._connectors[connector].transactionStarted = true;
 458           this._connectors[connector].transactionId = payload.transactionId;
 459           this._connectors[connector].lastConsumptionValue = 0;
 460           this._connectors[connector].lastSoC = 0;
 461           logger.info(this._basicFormatLog() + ' Transaction ' + this._connectors[connector].transactionId + ' STARTED on ' + this._stationInfo.name + '#' + requestPayload.connectorId + ' with idTag ' + requestPayload.idTag);
 462           this.sendStatusNotification(requestPayload.connectorId, 'Charging');
 463           const configuredMeterValueSampleInterval = this._configuration.configurationKey.find((value) => value.key === 'MeterValueSampleInterval');
 464           this.startMeterValues(requestPayload.connectorId,
 465               (configuredMeterValueSampleInterval ? configuredMeterValueSampleInterval.value * 1000 : 60000),
 466               this);
 467         }
 468       }
 469     } else {
 470       logger.error(this._basicFormatLog() + ' Starting transaction id ' + payload.transactionId + ' REJECTED with status ' + payload.idTagInfo.status + ', idTag ' + requestPayload.idTag);
 471       for (const connector in this._connectors) {
 472         if (Utils.convertToInt(connector) === Utils.convertToInt(requestPayload.connectorId)) {
 473           this._resetTransactionOnConnector(connector);
 474         }
 475       }
 476       this.sendStatusNotification(requestPayload.connectorId, 'Available');
 477     }
 478   }
 479
 480   async sendStatusNotification(connectorId, status, errorCode = 'NoError') {
 481     try {
 482       const payload = {
 483         connectorId,
 484         errorCode,
 485         status,
 486       };
 487       await this.sendMessage(uuid(), payload, Constants.OCPP_JSON_CALL_MESSAGE, 'StatusNotification');
 488     } catch (error) {
 489       logger.error(this._basicFormatLog() + ' Send status error: ' + error);
 490     }
 491   }
 492
 493   // eslint-disable-next-line class-methods-use-this
 494   async _startHeartbeat(self) {
 495     if (self._heartbeatInterval && !self._heartbeatSetInterval) {
 496       logger.info(self._basicFormatLog() + ' Heartbeat started every ' + self._heartbeatInterval + 'ms');
 497       self._heartbeatSetInterval = setInterval(() => {
 498         try {
 499           const payload = {
 500             currentTime: new Date().toISOString(),
 501           };
 502           self.sendMessage(uuid(), payload, Constants.OCPP_JSON_CALL_MESSAGE, 'Heartbeat');
 503         } catch (error) {
 504           logger.error(self._basicFormatLog() + ' Send heartbeat error: ' + error);
 505         }
 506       }, self._heartbeatInterval);
 507     } else {
 508       logger.error(self._basicFormatLog() + ' Heartbeat interval undefined, not starting the heartbeat');
 509     }
 510   }
 511
 512   async handleRequest(messageId, commandName, commandPayload) {
 513     let result;
 514     this._statistics.addMessage(commandName, true);
 515     // Call
 516     if (typeof this['handle' + commandName] === 'function') {
 517       try {
 518         // Call the method
 519         result = await this['handle' + commandName](commandPayload);
 520       } catch (error) {
 521         // Log
 522         logger.error(this._basicFormatLog() + ' Handle request error: ' + error);
 523         // Send back response to inform back end
 524         await this.sendError(messageId, error);
 525       }
 526     } else {
 527       // Throw exception
 528       await this.sendError(messageId, new OCPPError(Constants.OCPP_ERROR_NOT_IMPLEMENTED, 'Not implemented', {}));
 529       throw new Error(`${commandName} is not implemented ${JSON.stringify(commandPayload, null, ' ')}`);
 530     }
 531     // Send response
 532     await this.sendMessage(messageId, result, Constants.OCPP_JSON_CALL_RESULT_MESSAGE);
 533   }
 534
 535   async handleGetConfiguration() {
 536     return this._configuration;
 537   }
 538
 539   async handleChangeConfiguration(commandPayload) {
 540     const keyToChange = this._configuration.configurationKey.find((element) => element.key === commandPayload.key);
 541     if (keyToChange && !Utils.convertToBoolean(keyToChange.readonly)) {
 542       const keyIndex = this._configuration.configurationKey.indexOf(keyToChange);
 543       this._configuration.configurationKey[keyIndex].value = commandPayload.value;
 544       return Constants.OCPP_RESPONSE_ACCEPTED;
 545     }
 546     return Constants.OCPP_RESPONSE_REJECTED;
 547   }
 548
 549   async handleRemoteStartTransaction(commandPayload) {
 550     const transactionConnectorID = (commandPayload.connectorId ? commandPayload.connectorId : '1');
 551     if (this.hasAuthorizedTags() && this._getLocalAuthListEnabled() && this._getAuthorizeRemoteTxRequests()) {
 552       // Check if authorized
 553       if (this._authorizedTags.find((value) => value === commandPayload.idTag)) {
 554         // Authorization successful start transaction
 555         setTimeout(() => this.sendStartTransaction(transactionConnectorID, commandPayload.idTag), Constants.START_TRANSACTION_TIMEOUT);
 556         logger.debug(this._basicFormatLog() + ' Transaction remotely STARTED on ' + this._stationInfo.name + '#' + transactionConnectorID + ' with idTag ' + commandPayload.idTag);
 557         return Constants.OCPP_RESPONSE_ACCEPTED;
 558       }
 559       logger.error(this._basicFormatLog() + ' Remote starting transaction REJECTED with status ' + commandPayload.idTagInfo.status + ', idTag ' + commandPayload.idTag);
 560       return Constants.OCPP_RESPONSE_REJECTED;
 561     }
 562     // No local authorization check required => start transaction
 563     setTimeout(() => this.sendStartTransaction(transactionConnectorID, commandPayload.idTag), Constants.START_TRANSACTION_TIMEOUT);
 564     logger.debug(this._basicFormatLog() + ' Transaction remotely STARTED on ' + this._stationInfo.name + '#' + transactionConnectorID + ' with idTag ' + commandPayload.idTag);
 565     return Constants.OCPP_RESPONSE_ACCEPTED;
 566   }
 567
 568   async sendStartTransaction(connectorID, idTag) {
 569     try {
 570       const payload = {
 571         connectorId: connectorID,
 572         idTag,
 573         meterStart: 0,
 574         timestamp: new Date().toISOString(),
 575       };
 576       return await this.sendMessage(uuid(), payload, Constants.OCPP_JSON_CALL_MESSAGE, 'StartTransaction');
 577     } catch (error) {
 578       logger.error(this._basicFormatLog() + ' Send start transaction error: ' + error);
 579       this._resetTransactionOnConnector(connectorID);
 580       throw error;
 581     }
 582   }
 583
 584   async sendStopTransaction(transactionId, connectorID) {
 585     try {
 586       const payload = {
 587         transactionId,
 588         meterStop: 0,
 589         timestamp: new Date().toISOString(),
 590       };
 591       await this.sendMessage(uuid(), payload, Constants.OCPP_JSON_CALL_MESSAGE, 'StopTransaction');
 592       logger.info(this._basicFormatLog() + ' Transaction ' + this._connectors[connectorID].transactionId + ' STOPPED on ' + this._stationInfo.name + '#' + connectorID);
 593       this.sendStatusNotification(connectorID, 'Available');
 594     } catch (error) {
 595       logger.error(this._basicFormatLog() + ' Send stop transaction error: ' + error);
 596       throw error;
 597     } finally {
 598       this._resetTransactionOnConnector(connectorID);
 599     }
 600   }
 601
 602   _resetTransactionOnConnector(connectorID) {
 603     this._connectors[connectorID].transactionStarted = false;
 604     this._connectors[connectorID].transactionId = null;
 605     this._connectors[connectorID].lastConsumptionValue = -1;
 606     this._connectors[connectorID].lastSoC = -1;
 607     if (this._connectors[connectorID].transactionInterval) {
 608       clearInterval(this._connectors[connectorID].transactionInterval);
 609     }
 610   }
 611
 612   // eslint-disable-next-line class-methods-use-this
 613   async sendMeterValues(connectorID, interval, self) {
 614     try {
 615       const sampledValueLcl = {
 616         timestamp: new Date().toISOString(),
 617       };
 618       const meterValuesClone = Utils.cloneJSonDocument(self._getConnector(connectorID).MeterValues);
 619       if (Array.isArray(meterValuesClone)) {
 620         sampledValueLcl.sampledValue = meterValuesClone;
 621       } else {
 622         sampledValueLcl.sampledValue = [meterValuesClone];
 623       }
 624       for (let index = 0; index < sampledValueLcl.sampledValue.length; index++) {
 625         if (sampledValueLcl.sampledValue[index].measurand && sampledValueLcl.sampledValue[index].measurand === 'SoC') {
 626           sampledValueLcl.sampledValue[index].value = Math.floor(Math.random() * 100) + 1;
 627           if (sampledValueLcl.sampledValue[index].value > 100) {
 628             logger.info(self._basicFormatLog() + ' Meter type: ' +
 629               (sampledValueLcl.sampledValue[index].measurand ? sampledValueLcl.sampledValue[index].measurand : 'default') +
 630               ' value: ' + sampledValueLcl.sampledValue[index].value);
 631           }
 632         } else {
 633           // Persist previous value in connector
 634           const connector = self._connectors[connectorID];
 635           let consumption;
 636           consumption = Utils.getRandomInt(self._stationInfo.maxPower / 3600000 * interval, 4);
 637           if (connector && connector.lastConsumptionValue >= 0) {
 638             connector.lastConsumptionValue += consumption;
 639           } else {
 640             connector.lastConsumptionValue = 0;
 641           }
 642           consumption = Math.round(connector.lastConsumptionValue * 3600 / interval);
 643           logger.info(self._basicFormatLog() + ' ConnectorID ' + connectorID + ' transaction ' + connector.transactionId + ' value ' + connector.lastConsumptionValue);
 644           sampledValueLcl.sampledValue[index].value = connector.lastConsumptionValue;
 645           if (sampledValueLcl.sampledValue[index].value > (self._stationInfo.maxPower * 3600 / interval) || sampledValueLcl.sampledValue[index].value < 500) {
 646             logger.info(self._basicFormatLog() + ' Meter type: ' +
 647               (sampledValueLcl.sampledValue[index].measurand ? sampledValueLcl.sampledValue[index].measurand : 'default') +
 648               ' value: ' + sampledValueLcl.sampledValue[index].value + '/' + (self._stationInfo.maxPower * 3600 / interval));
 649           }
 650         }
 651       }
 652
 653       const payload = {
 654         connectorId: connectorID,
 655         transactionId: self._connectors[connectorID].transactionId,
 656         meterValue: [sampledValueLcl],
 657       };
 658       await self.sendMessage(uuid(), payload, Constants.OCPP_JSON_CALL_MESSAGE, 'MeterValues');
 659     } catch (error) {
 660       logger.error(self._basicFormatLog() + ' Send meter values error: ' + error);
 661     }
 662   }
 663
 664   async startMeterValues(connectorID, interval, self) {
 665     if (!this._connectors[connectorID].transactionStarted) {
 666       logger.debug(`${self._basicFormatLog()} Trying to start meter values on connector ID ${connectorID} with no transaction started`);
 667     } else if (this._connectors[connectorID].transactionStarted && !this._connectors[connectorID].transactionId) {
 668       logger.debug(`${self._basicFormatLog()} Trying to start meter values on connector ID ${connectorID} with no transaction id`);
 669     }
 670     this._connectors[connectorID].transactionInterval = setInterval(async () => {
 671       const sendMeterValues = performance.timerify(this.sendMeterValues);
 672       this._performanceObserver.observe({
 673         entryTypes: ['function'],
 674       });
 675       await sendMeterValues(connectorID, interval, self);
 676     }, interval);
 677   }
 678
 679   async handleRemoteStopTransaction(commandPayload) {
 680     for (const connector in this._connectors) {
 681       if (this._connectors[connector].transactionId === commandPayload.transactionId) {
 682         this.sendStopTransaction(commandPayload.transactionId, connector);
 683       }
 684     }
 685     return Constants.OCPP_RESPONSE_ACCEPTED;
 686   }
 687
 688   hasAuthorizedTags() {
 689     return Array.isArray(this._authorizedTags) && this._authorizedTags.length > 0;
 690   }
 691
 692   getRandomTagId() {
 693     const index = Math.round(Math.floor(Math.random() * this._authorizedTags.length - 1));
 694     return this._authorizedTags[index];
 695   }
 696
 697   _getConnector(number) {
 698     return this._stationInfo.Connectors[number];
 699   }
 700 }
 701
 702 module.exports = ChargingStation;