Use crypto unbiased random integer generator
[e-mobility-charging-stations-simulator.git] / src / charging-station / AutomaticTransactionGenerator.ts
index dddfc045c9a80aba7e56ab3e985727188bbd6f87..60760be136ff773cc047092a46f5df4e151bfaf0 100644 (file)
@@ -1,29 +1,79 @@
-// Partial Copyright Jerome Benoit. 2021. All Rights Reserved.
+// Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
 
-import { AuthorizationStatus, AuthorizeResponse, StartTransactionResponse, StopTransactionReason, StopTransactionResponse } from '../types/ocpp/Transaction';
+import { AsyncResource } from 'async_hooks';
 
-import ChargingStation from './ChargingStation';
-import Constants from '../utils/Constants';
+import type ChargingStation from './ChargingStation';
+import { ChargingStationUtils } from './ChargingStationUtils';
+import BaseError from '../exception/BaseError';
 import PerformanceStatistics from '../performance/PerformanceStatistics';
-import { Status } from '../types/AutomaticTransactionGenerator';
-import Utils from '../utils/Utils';
+import {
+  type AutomaticTransactionGeneratorConfiguration,
+  IdTagDistribution,
+  type Status,
+} from '../types/AutomaticTransactionGenerator';
+import { RequestCommand } from '../types/ocpp/Requests';
+import {
+  AuthorizationStatus,
+  type AuthorizeRequest,
+  type AuthorizeResponse,
+  type StartTransactionRequest,
+  type StartTransactionResponse,
+  StopTransactionReason,
+  type StopTransactionResponse,
+} from '../types/ocpp/Transaction';
+import Constants from '../utils/Constants';
 import logger from '../utils/Logger';
+import Utils from '../utils/Utils';
 
-export default class AutomaticTransactionGenerator {
+const moduleName = 'AutomaticTransactionGenerator';
+
+export default class AutomaticTransactionGenerator extends AsyncResource {
+  private static readonly instances: Map<string, AutomaticTransactionGenerator> = new Map<
+    string,
+    AutomaticTransactionGenerator
+  >();
+
+  public readonly connectorsStatus: Map<number, Status>;
+  public readonly configuration: AutomaticTransactionGeneratorConfiguration;
   public started: boolean;
   private readonly chargingStation: ChargingStation;
-  private readonly connectorsStatus: Map<number, Status>;
+  private idTagIndex: number;
 
-  constructor(chargingStation: ChargingStation) {
+  private constructor(
+    automaticTransactionGeneratorConfiguration: AutomaticTransactionGeneratorConfiguration,
+    chargingStation: ChargingStation
+  ) {
+    super(moduleName);
+    this.started = false;
+    this.configuration = automaticTransactionGeneratorConfiguration;
     this.chargingStation = chargingStation;
+    this.idTagIndex = 0;
     this.connectorsStatus = new Map<number, Status>();
-    this.stopConnectors();
-    this.started = false;
+    this.initializeConnectorsStatus();
+  }
+
+  public static getInstance(
+    automaticTransactionGeneratorConfiguration: AutomaticTransactionGeneratorConfiguration,
+    chargingStation: ChargingStation
+  ): AutomaticTransactionGenerator {
+    if (AutomaticTransactionGenerator.instances.has(chargingStation.stationInfo.hashId) === false) {
+      AutomaticTransactionGenerator.instances.set(
+        chargingStation.stationInfo.hashId,
+        new AutomaticTransactionGenerator(
+          automaticTransactionGeneratorConfiguration,
+          chargingStation
+        )
+      );
+    }
+    return AutomaticTransactionGenerator.instances.get(chargingStation.stationInfo.hashId);
   }
 
   public start(): void {
-    if (this.started) {
-      logger.error(`${this.logPrefix()} trying to start while already started`);
+    if (this.checkChargingStation() === false) {
+      return;
+    }
+    if (this.started === true) {
+      logger.warn(`${this.logPrefix()} is already started`);
       return;
     }
     this.startConnectors();
@@ -31,17 +81,57 @@ export default class AutomaticTransactionGenerator {
   }
 
   public stop(): void {
-    if (!this.started) {
-      logger.error(`${this.logPrefix()} trying to stop while not started`);
+    if (this.started === false) {
+      logger.warn(`${this.logPrefix()} is already stopped`);
       return;
     }
     this.stopConnectors();
     this.started = false;
   }
 
+  public startConnector(connectorId: number): void {
+    if (this.checkChargingStation(connectorId) === false) {
+      return;
+    }
+    if (this.connectorsStatus.has(connectorId) === false) {
+      logger.error(`${this.logPrefix(connectorId)} starting on non existing connector`);
+      throw new BaseError(`Connector ${connectorId} does not exist`);
+    }
+    if (this.connectorsStatus.get(connectorId)?.start === false) {
+      this.runInAsyncScope(
+        this.internalStartConnector.bind(this) as (
+          this: AutomaticTransactionGenerator,
+          ...args: any[]
+        ) => Promise<void>,
+        this,
+        connectorId
+      ).catch(() => {
+        /* This is intentional */
+      });
+    } else if (this.connectorsStatus.get(connectorId)?.start === true) {
+      logger.warn(`${this.logPrefix(connectorId)} is already started on connector`);
+    }
+  }
+
+  public stopConnector(connectorId: number): void {
+    if (this.connectorsStatus.has(connectorId) === false) {
+      logger.error(`${this.logPrefix(connectorId)} stopping on non existing connector`);
+      throw new BaseError(`Connector ${connectorId} does not exist`);
+    }
+    if (this.connectorsStatus.get(connectorId)?.start === true) {
+      this.connectorsStatus.get(connectorId).start = false;
+    } else if (this.connectorsStatus.get(connectorId)?.start === false) {
+      logger.warn(`${this.logPrefix(connectorId)} is already stopped on connector`);
+    }
+  }
+
   private startConnectors(): void {
-    if (this.connectorsStatus?.size > 0 && this.connectorsStatus.size !== this.chargingStation.getNumberOfConnectors()) {
+    if (
+      this.connectorsStatus?.size > 0 &&
+      this.connectorsStatus.size !== this.chargingStation.getNumberOfConnectors()
+    ) {
       this.connectorsStatus.clear();
+      this.initializeConnectorsStatus();
     }
     for (const connectorId of this.chargingStation.connectors.keys()) {
       if (connectorId > 0) {
@@ -59,159 +149,316 @@ export default class AutomaticTransactionGenerator {
   }
 
   private async internalStartConnector(connectorId: number): Promise<void> {
-    this.initStartConnectorStatus(connectorId);
-    logger.info(this.logPrefix(connectorId) + ' started on connector and will run for ' + Utils.formatDurationMilliSeconds(this.connectorsStatus.get(connectorId).stopDate.getTime() - this.connectorsStatus.get(connectorId).startDate.getTime()));
-    while (this.connectorsStatus.get(connectorId).start) {
-      if ((new Date()) > this.connectorsStatus.get(connectorId).stopDate) {
+    this.setStartConnectorStatus(connectorId);
+    logger.info(
+      this.logPrefix(connectorId) +
+        ' started on connector and will run for ' +
+        Utils.formatDurationMilliSeconds(
+          this.connectorsStatus.get(connectorId).stopDate.getTime() -
+            this.connectorsStatus.get(connectorId).startDate.getTime()
+        )
+    );
+    while (this.connectorsStatus.get(connectorId).start === true) {
+      if (new Date() > this.connectorsStatus.get(connectorId).stopDate) {
         this.stopConnector(connectorId);
         break;
       }
-      if (!this.chargingStation.isInAcceptedState()) {
-        logger.error(this.logPrefix(connectorId) + ' entered in transaction loop while the charging station is not in accepted state');
+      if (this.chargingStation.isInAcceptedState() === false) {
+        logger.error(
+          this.logPrefix(connectorId) +
+            ' entered in transaction loop while the charging station is not in accepted state'
+        );
         this.stopConnector(connectorId);
         break;
       }
-      if (!this.chargingStation.isChargingStationAvailable()) {
-        logger.info(this.logPrefix(connectorId) + ' entered in transaction loop while the charging station is unavailable');
+      if (this.chargingStation.isChargingStationAvailable() === false) {
+        logger.info(
+          this.logPrefix(connectorId) +
+            ' entered in transaction loop while the charging station is unavailable'
+        );
         this.stopConnector(connectorId);
         break;
       }
-      if (!this.chargingStation.isConnectorAvailable(connectorId)) {
-        logger.info(`${this.logPrefix(connectorId)} entered in transaction loop while the connector ${connectorId} is unavailable`);
+      if (this.chargingStation.isConnectorAvailable(connectorId) === false) {
+        logger.info(
+          `${this.logPrefix(
+            connectorId
+          )} entered in transaction loop while the connector ${connectorId} is unavailable`
+        );
         this.stopConnector(connectorId);
         break;
       }
       if (!this.chargingStation?.ocppRequestService) {
-        logger.info(`${this.logPrefix(connectorId)} transaction loop waiting for charging station service to be initialized`);
+        logger.info(
+          `${this.logPrefix(
+            connectorId
+          )} transaction loop waiting for charging station service to be initialized`
+        );
         do {
           await Utils.sleep(Constants.CHARGING_STATION_ATG_INITIALIZATION_TIME);
         } while (!this.chargingStation?.ocppRequestService);
       }
-      const wait = Utils.getRandomInteger(this.chargingStation.stationInfo.AutomaticTransactionGenerator.maxDelayBetweenTwoTransactions,
-        this.chargingStation.stationInfo.AutomaticTransactionGenerator.minDelayBetweenTwoTransactions) * 1000;
-      logger.info(this.logPrefix(connectorId) + ' waiting for ' + Utils.formatDurationMilliSeconds(wait));
+      const wait =
+        Utils.getRandomInteger(
+          this.configuration.maxDelayBetweenTwoTransactions,
+          this.configuration.minDelayBetweenTwoTransactions
+        ) * 1000;
+      logger.info(
+        this.logPrefix(connectorId) + ' waiting for ' + Utils.formatDurationMilliSeconds(wait)
+      );
       await Utils.sleep(wait);
       const start = Utils.secureRandom();
-      if (start < this.chargingStation.stationInfo.AutomaticTransactionGenerator.probabilityOfStart) {
+      if (start < this.configuration.probabilityOfStart) {
         this.connectorsStatus.get(connectorId).skippedConsecutiveTransactions = 0;
         // Start transaction
         const startResponse = await this.startTransaction(connectorId);
-        this.connectorsStatus.get(connectorId).startTransactionRequests++;
-        if (startResponse?.idTagInfo?.status !== AuthorizationStatus.ACCEPTED) {
-          logger.warn(this.logPrefix(connectorId) + ' start transaction rejected');
-          this.connectorsStatus.get(connectorId).rejectedStartTransactionRequests++;
-        } else {
+        if (startResponse?.idTagInfo?.status === AuthorizationStatus.ACCEPTED) {
           // Wait until end of transaction
-          const waitTrxEnd = Utils.getRandomInteger(this.chargingStation.stationInfo.AutomaticTransactionGenerator.maxDuration,
-            this.chargingStation.stationInfo.AutomaticTransactionGenerator.minDuration) * 1000;
-          logger.info(this.logPrefix(connectorId) + ' transaction ' + this.chargingStation.getConnectorStatus(connectorId).transactionId.toString() + ' started and will stop in ' + Utils.formatDurationMilliSeconds(waitTrxEnd));
-          this.connectorsStatus.get(connectorId).acceptedStartTransactionRequests++;
+          const waitTrxEnd =
+            Utils.getRandomInteger(this.configuration.maxDuration, this.configuration.minDuration) *
+            1000;
+          logger.info(
+            this.logPrefix(connectorId) +
+              ' transaction ' +
+              this.chargingStation.getConnectorStatus(connectorId).transactionId.toString() +
+              ' started and will stop in ' +
+              Utils.formatDurationMilliSeconds(waitTrxEnd)
+          );
           await Utils.sleep(waitTrxEnd);
           // Stop transaction
-          logger.info(this.logPrefix(connectorId) + ' stop transaction ' + this.chargingStation.getConnectorStatus(connectorId).transactionId.toString());
+          logger.info(
+            this.logPrefix(connectorId) +
+              ' stop transaction ' +
+              this.chargingStation.getConnectorStatus(connectorId).transactionId.toString()
+          );
           await this.stopTransaction(connectorId);
         }
       } else {
         this.connectorsStatus.get(connectorId).skippedConsecutiveTransactions++;
         this.connectorsStatus.get(connectorId).skippedTransactions++;
-        logger.info(this.logPrefix(connectorId) + ' skipped consecutively ' + this.connectorsStatus.get(connectorId).skippedConsecutiveTransactions.toString() + '/' + this.connectorsStatus.get(connectorId).skippedTransactions.toString() + ' transaction(s)');
+        logger.info(
+          this.logPrefix(connectorId) +
+            ' skipped consecutively ' +
+            this.connectorsStatus.get(connectorId).skippedConsecutiveTransactions.toString() +
+            '/' +
+            this.connectorsStatus.get(connectorId).skippedTransactions.toString() +
+            ' transaction(s)'
+        );
       }
       this.connectorsStatus.get(connectorId).lastRunDate = new Date();
     }
-    await this.stopTransaction(connectorId);
     this.connectorsStatus.get(connectorId).stoppedDate = new Date();
-    logger.info(this.logPrefix(connectorId) + ' stopped on connector and lasted for ' + Utils.formatDurationMilliSeconds(this.connectorsStatus.get(connectorId).stoppedDate.getTime() - this.connectorsStatus.get(connectorId).startDate.getTime()));
-    logger.debug(`${this.logPrefix(connectorId)} connector status %j`, this.connectorsStatus.get(connectorId));
+    logger.info(
+      this.logPrefix(connectorId) +
+        ' stopped on connector and lasted for ' +
+        Utils.formatDurationMilliSeconds(
+          this.connectorsStatus.get(connectorId).stoppedDate.getTime() -
+            this.connectorsStatus.get(connectorId).startDate.getTime()
+        )
+    );
+    logger.debug(
+      `${this.logPrefix(connectorId)} connector status: %j`,
+      this.connectorsStatus.get(connectorId)
+    );
   }
 
-  private startConnector(connectorId: number): void {
-    // Avoid hogging the event loop with a busy loop
-    setImmediate(() => {
-      this.internalStartConnector(connectorId).catch(() => { /* This is intentional */ });
-    });
-  }
-
-  private stopConnector(connectorId: number): void {
-    this.connectorsStatus.set(connectorId, { ...this.connectorsStatus.get(connectorId), start: false });
-  }
-
-  private initStartConnectorStatus(connectorId: number): void {
-    this.connectorsStatus.get(connectorId).authorizeRequests = this?.connectorsStatus.get(connectorId)?.authorizeRequests ?? 0;
-    this.connectorsStatus.get(connectorId).acceptedAuthorizeRequests = this?.connectorsStatus.get(connectorId)?.acceptedAuthorizeRequests ?? 0;
-    this.connectorsStatus.get(connectorId).rejectedAuthorizeRequests = this?.connectorsStatus.get(connectorId)?.rejectedAuthorizeRequests ?? 0;
-    this.connectorsStatus.get(connectorId).startTransactionRequests = this?.connectorsStatus.get(connectorId)?.startTransactionRequests ?? 0;
-    this.connectorsStatus.get(connectorId).acceptedStartTransactionRequests = this?.connectorsStatus.get(connectorId)?.acceptedStartTransactionRequests ?? 0;
-    this.connectorsStatus.get(connectorId).rejectedStartTransactionRequests = this?.connectorsStatus.get(connectorId)?.rejectedStartTransactionRequests ?? 0;
-    this.connectorsStatus.get(connectorId).stopTransactionRequests = this?.connectorsStatus.get(connectorId)?.stopTransactionRequests ?? 0;
+  private setStartConnectorStatus(connectorId: number): void {
     this.connectorsStatus.get(connectorId).skippedConsecutiveTransactions = 0;
-    this.connectorsStatus.get(connectorId).skippedTransactions = this?.connectorsStatus.get(connectorId)?.skippedTransactions ?? 0;
-    const previousRunDuration = (this?.connectorsStatus.get(connectorId)?.startDate && this?.connectorsStatus.get(connectorId)?.lastRunDate)
-      ? (this.connectorsStatus.get(connectorId).lastRunDate.getTime() - this.connectorsStatus.get(connectorId).startDate.getTime())
-      : 0;
+    const previousRunDuration =
+      this?.connectorsStatus.get(connectorId)?.startDate &&
+      this?.connectorsStatus.get(connectorId)?.lastRunDate
+        ? this.connectorsStatus.get(connectorId).lastRunDate.getTime() -
+          this.connectorsStatus.get(connectorId).startDate.getTime()
+        : 0;
     this.connectorsStatus.get(connectorId).startDate = new Date();
-    this.connectorsStatus.get(connectorId).stopDate = new Date(this.connectorsStatus.get(connectorId).startDate.getTime()
-      + (this.chargingStation.stationInfo?.AutomaticTransactionGenerator?.stopAfterHours ?? Constants.CHARGING_STATION_ATG_DEFAULT_STOP_AFTER_HOURS) * 3600 * 1000
-      - previousRunDuration);
+    this.connectorsStatus.get(connectorId).stopDate = new Date(
+      this.connectorsStatus.get(connectorId).startDate.getTime() +
+        (this.configuration.stopAfterHours ??
+          Constants.CHARGING_STATION_ATG_DEFAULT_STOP_AFTER_HOURS) *
+          3600 *
+          1000 -
+        previousRunDuration
+    );
     this.connectorsStatus.get(connectorId).start = true;
   }
 
-  private async startTransaction(connectorId: number): Promise<StartTransactionResponse | AuthorizeResponse> {
+  private initializeConnectorsStatus(): void {
+    for (const connectorId of this.chargingStation.connectors.keys()) {
+      if (connectorId > 0) {
+        this.connectorsStatus.set(connectorId, {
+          start: false,
+          authorizeRequests: 0,
+          acceptedAuthorizeRequests: 0,
+          rejectedAuthorizeRequests: 0,
+          startTransactionRequests: 0,
+          acceptedStartTransactionRequests: 0,
+          rejectedStartTransactionRequests: 0,
+          stopTransactionRequests: 0,
+          acceptedStopTransactionRequests: 0,
+          rejectedStopTransactionRequests: 0,
+          skippedConsecutiveTransactions: 0,
+          skippedTransactions: 0,
+        });
+      }
+    }
+  }
+
+  private async startTransaction(
+    connectorId: number
+  ): Promise<StartTransactionResponse | undefined> {
     const measureId = 'StartTransaction with ATG';
     const beginId = PerformanceStatistics.beginMeasure(measureId);
     let startResponse: StartTransactionResponse;
     if (this.chargingStation.hasAuthorizedTags()) {
-      const idTag = this.chargingStation.getRandomIdTag();
-      if (this.chargingStation.getAutomaticTransactionGeneratorRequireAuthorize()) {
+      const idTag = this.getIdTag(connectorId);
+      const startTransactionLogMsg = `${this.logPrefix(
+        connectorId
+      )} start transaction with an idTag '${idTag}'`;
+      if (this.getRequireAuthorize()) {
+        this.chargingStation.getConnectorStatus(connectorId).authorizeIdTag = idTag;
         // Authorize idTag
-        const authorizeResponse = await this.chargingStation.ocppRequestService.sendAuthorize(connectorId, idTag);
+        const authorizeResponse: AuthorizeResponse =
+          await this.chargingStation.ocppRequestService.requestHandler<
+            AuthorizeRequest,
+            AuthorizeResponse
+          >(this.chargingStation, RequestCommand.AUTHORIZE, {
+            idTag,
+          });
         this.connectorsStatus.get(connectorId).authorizeRequests++;
         if (authorizeResponse?.idTagInfo?.status === AuthorizationStatus.ACCEPTED) {
           this.connectorsStatus.get(connectorId).acceptedAuthorizeRequests++;
-          logger.info(this.logPrefix(connectorId) + ' start transaction for idTag ' + idTag);
+          logger.info(startTransactionLogMsg);
           // Start transaction
-          startResponse = await this.chargingStation.ocppRequestService.sendStartTransaction(connectorId, idTag);
+          startResponse = await this.chargingStation.ocppRequestService.requestHandler<
+            StartTransactionRequest,
+            StartTransactionResponse
+          >(this.chargingStation, RequestCommand.START_TRANSACTION, {
+            connectorId,
+            idTag,
+          });
+          this.handleStartTransactionResponse(connectorId, startResponse);
           PerformanceStatistics.endMeasure(measureId, beginId);
           return startResponse;
         }
         this.connectorsStatus.get(connectorId).rejectedAuthorizeRequests++;
         PerformanceStatistics.endMeasure(measureId, beginId);
-        return authorizeResponse;
+        return startResponse;
       }
-      logger.info(this.logPrefix(connectorId) + ' start transaction for idTag ' + idTag);
+      logger.info(startTransactionLogMsg);
       // Start transaction
-      startResponse = await this.chargingStation.ocppRequestService.sendStartTransaction(connectorId, idTag);
+      startResponse = await this.chargingStation.ocppRequestService.requestHandler<
+        StartTransactionRequest,
+        StartTransactionResponse
+      >(this.chargingStation, RequestCommand.START_TRANSACTION, {
+        connectorId,
+        idTag,
+      });
+      this.handleStartTransactionResponse(connectorId, startResponse);
       PerformanceStatistics.endMeasure(measureId, beginId);
       return startResponse;
     }
-    logger.info(this.logPrefix(connectorId) + ' start transaction without an idTag');
-    startResponse = await this.chargingStation.ocppRequestService.sendStartTransaction(connectorId);
+    logger.info(`${this.logPrefix(connectorId)} start transaction without an idTag`);
+    startResponse = await this.chargingStation.ocppRequestService.requestHandler<
+      StartTransactionRequest,
+      StartTransactionResponse
+    >(this.chargingStation, RequestCommand.START_TRANSACTION, { connectorId });
+    this.handleStartTransactionResponse(connectorId, startResponse);
     PerformanceStatistics.endMeasure(measureId, beginId);
     return startResponse;
   }
 
-  private async stopTransaction(connectorId: number, reason: StopTransactionReason = StopTransactionReason.NONE): Promise<StopTransactionResponse> {
+  private async stopTransaction(
+    connectorId: number,
+    reason: StopTransactionReason = StopTransactionReason.LOCAL
+  ): Promise<StopTransactionResponse> {
     const measureId = 'StopTransaction with ATG';
     const beginId = PerformanceStatistics.beginMeasure(measureId);
-    let transactionId = 0;
     let stopResponse: StopTransactionResponse;
-    if (this.chargingStation.getConnectorStatus(connectorId)?.transactionStarted) {
-      transactionId = this.chargingStation.getConnectorStatus(connectorId).transactionId;
-      stopResponse = await this.chargingStation.ocppRequestService.sendStopTransaction(transactionId,
-        this.chargingStation.getEnergyActiveImportRegisterByTransactionId(transactionId),
-        this.chargingStation.getTransactionIdTag(transactionId),
-        reason);
+    if (this.chargingStation.getConnectorStatus(connectorId)?.transactionStarted === true) {
+      stopResponse = await this.chargingStation.stopTransactionOnConnector(connectorId, reason);
       this.connectorsStatus.get(connectorId).stopTransactionRequests++;
+      if (stopResponse?.idTagInfo?.status === AuthorizationStatus.ACCEPTED) {
+        this.connectorsStatus.get(connectorId).acceptedStopTransactionRequests++;
+      } else {
+        this.connectorsStatus.get(connectorId).rejectedStopTransactionRequests++;
+      }
     } else {
-      logger.warn(`${this.logPrefix(connectorId)} trying to stop a not started transaction${transactionId ? ' ' + transactionId.toString() : ''}`);
+      const transactionId = this.chargingStation.getConnectorStatus(connectorId).transactionId;
+      logger.warn(
+        `${this.logPrefix(connectorId)} stopping a not started transaction${
+          transactionId ? ' ' + transactionId.toString() : ''
+        }`
+      );
     }
     PerformanceStatistics.endMeasure(measureId, beginId);
     return stopResponse;
   }
 
+  private getRequireAuthorize(): boolean {
+    return this.configuration?.requireAuthorize ?? true;
+  }
+
+  private getRandomIdTag(authorizationFile: string): string {
+    const tags = this.chargingStation.authorizedTagsCache.getAuthorizedTags(authorizationFile);
+    this.idTagIndex = Math.floor(Utils.secureRandom() * tags.length);
+    return tags[this.idTagIndex];
+  }
+
+  private getRoundRobinIdTag(authorizationFile: string): string {
+    const tags = this.chargingStation.authorizedTagsCache.getAuthorizedTags(authorizationFile);
+    const idTag = tags[this.idTagIndex];
+    this.idTagIndex = this.idTagIndex === tags.length - 1 ? 0 : this.idTagIndex + 1;
+    return idTag;
+  }
+
+  private getConnectorAffinityIdTag(authorizationFile: string, connectorId: number): string {
+    const tags = this.chargingStation.authorizedTagsCache.getAuthorizedTags(authorizationFile);
+    this.idTagIndex = (this.chargingStation.index - 1 + (connectorId - 1)) % tags.length;
+    return tags[this.idTagIndex];
+  }
+
+  private getIdTag(connectorId: number): string {
+    const authorizationFile = ChargingStationUtils.getAuthorizationFile(
+      this.chargingStation.stationInfo
+    );
+    switch (this.configuration?.idTagDistribution) {
+      case IdTagDistribution.RANDOM:
+        return this.getRandomIdTag(authorizationFile);
+      case IdTagDistribution.ROUND_ROBIN:
+        return this.getRoundRobinIdTag(authorizationFile);
+      case IdTagDistribution.CONNECTOR_AFFINITY:
+        return this.getConnectorAffinityIdTag(authorizationFile, connectorId);
+      default:
+        return this.getRoundRobinIdTag(authorizationFile);
+    }
+  }
+
   private logPrefix(connectorId?: number): string {
-    if (connectorId) {
-      return Utils.logPrefix(' ' + this.chargingStation.stationInfo.chargingStationId + ' | ATG on connector #' + connectorId.toString() + ':');
+    return Utils.logPrefix(
+      ` ${this.chargingStation.stationInfo.chargingStationId} | ATG${
+        connectorId !== undefined ? ` on connector #${connectorId.toString()}` : ''
+      }:`
+    );
+  }
+
+  private handleStartTransactionResponse(
+    connectorId: number,
+    startResponse: StartTransactionResponse
+  ): void {
+    this.connectorsStatus.get(connectorId).startTransactionRequests++;
+    if (startResponse?.idTagInfo?.status === AuthorizationStatus.ACCEPTED) {
+      this.connectorsStatus.get(connectorId).acceptedStartTransactionRequests++;
+    } else {
+      logger.warn(this.logPrefix(connectorId) + ' start transaction rejected');
+      this.connectorsStatus.get(connectorId).rejectedStartTransactionRequests++;
+    }
+  }
+
+  private checkChargingStation(connectorId?: number): boolean {
+    if (this.chargingStation.started === false && this.chargingStation.starting === false) {
+      logger.warn(`${this.logPrefix(connectorId)} charging station is stopped, cannot proceed`);
+      return false;
     }
-    return Utils.logPrefix(' ' + this.chargingStation.stationInfo.chargingStationId + ' | ATG:');
+    return true;
   }
 }