X-Git-Url: https://git.piment-noir.org/?a=blobdiff_plain;f=src%2Fcharging-station%2Focpp%2FOCPPRequestService.ts;h=bdfffc3725973ab6b5521889cce9f9b245e8bc24;hb=ea32ea059bfdd7134abe2ba349985e5b15bc1d06;hp=0bfa2b221c55ebc79e810b5a2845c5bcde4b7fd8;hpb=caad9d6b03dbfc507da6d8e79ccbbaf74593e981;p=e-mobility-charging-stations-simulator.git

diff --git a/src/charging-station/ocpp/OCPPRequestService.ts b/src/charging-station/ocpp/OCPPRequestService.ts
index 0bfa2b22..d7757eaa 100644
--- a/src/charging-station/ocpp/OCPPRequestService.ts
+++ b/src/charging-station/ocpp/OCPPRequestService.ts
@@ -1,157 +1,488 @@
-import { AuthorizeResponse, StartTransactionResponse, StopTransactionReason, StopTransactionResponse } from '../../types/ocpp/Transaction';
-import { DiagnosticsStatus, IncomingRequestCommand, RequestCommand, SendParams } from '../../types/ocpp/Requests';
-
-import { BootNotificationResponse } from '../../types/ocpp/Responses';
-import { ChargePointErrorCode } from '../../types/ocpp/ChargePointErrorCode';
-import { ChargePointStatus } from '../../types/ocpp/ChargePointStatus';
-import ChargingStation from '../ChargingStation';
-import Constants from '../../utils/Constants';
-import { ErrorType } from '../../types/ocpp/ErrorType';
-import { MessageType } from '../../types/ocpp/MessageType';
-import { MeterValue } from '../../types/ocpp/MeterValues';
-import OCPPError from '../../exception/OCPPError';
-import OCPPResponseService from './OCPPResponseService';
-import PerformanceStatistics from '../../performance/PerformanceStatistics';
-import Utils from '../../utils/Utils';
-import logger from '../../utils/Logger';
-
-export default abstract class OCPPRequestService {
-  public chargingStation: ChargingStation;
-  protected ocppResponseService: OCPPResponseService;
-
-  constructor(chargingStation: ChargingStation, ocppResponseService: OCPPResponseService) {
-    this.chargingStation = chargingStation;
-    this.ocppResponseService = ocppResponseService;
+import _Ajv, { type ValidateFunction } from 'ajv'
+import _ajvFormats from 'ajv-formats'
+
+import type { ChargingStation } from '../../charging-station/index.js'
+import { OCPPError } from '../../exception/index.js'
+import { PerformanceStatistics } from '../../performance/index.js'
+import {
+  ChargingStationEvents,
+  type ErrorCallback,
+  type ErrorResponse,
+  ErrorType,
+  type IncomingRequestCommand,
+  type JsonType,
+  MessageType,
+  type OCPPVersion,
+  type OutgoingRequest,
+  RequestCommand,
+  type RequestParams,
+  type Response,
+  type ResponseCallback,
+  type ResponseType
+} from '../../types/index.js'
+import {
+  clone,
+  formatDurationMilliSeconds,
+  handleSendMessageError,
+  logger
+} from '../../utils/index.js'
+import { OCPPConstants } from './OCPPConstants.js'
+import type { OCPPResponseService } from './OCPPResponseService.js'
+import { OCPPServiceUtils } from './OCPPServiceUtils.js'
+type Ajv = _Ajv.default
+// eslint-disable-next-line @typescript-eslint/no-redeclare
+const Ajv = _Ajv.default
+const ajvFormats = _ajvFormats.default
+
+const moduleName = 'OCPPRequestService'
+
+const defaultRequestParams: RequestParams = {
+  skipBufferingOnError: false,
+  triggerMessage: false,
+  throwError: false
+}
+
+export abstract class OCPPRequestService {
+  private static instance: OCPPRequestService | null = null
+  private readonly version: OCPPVersion
+  private readonly ocppResponseService: OCPPResponseService
+  protected readonly ajv: Ajv
+  protected abstract payloadValidateFunctions: Map<RequestCommand, ValidateFunction<JsonType>>
+
+  protected constructor (version: OCPPVersion, ocppResponseService: OCPPResponseService) {
+    this.version = version
+    this.ajv = new Ajv({
+      keywords: ['javaType'],
+      multipleOfPrecision: 2
+    })
+    ajvFormats(this.ajv)
+    this.ocppResponseService = ocppResponseService
+    this.requestHandler = this.requestHandler.bind(this)
+    this.sendMessage = this.sendMessage.bind(this)
+    this.sendResponse = this.sendResponse.bind(this)
+    this.sendError = this.sendError.bind(this)
+    this.internalSendMessage = this.internalSendMessage.bind(this)
+    this.buildMessageToSend = this.buildMessageToSend.bind(this)
+    this.validateRequestPayload = this.validateRequestPayload.bind(this)
+    this.validateIncomingRequestResponsePayload =
+      this.validateIncomingRequestResponsePayload.bind(this)
   }
 
-  public async sendMessage(messageId: string, messageData: any, messageType: MessageType, commandName: RequestCommand | IncomingRequestCommand,
-      params: SendParams = {
-        skipBufferingOnError: false,
-        triggerMessage: false
-      }): Promise<unknown> {
-    if ((this.chargingStation.isInPendingState() && !params.triggerMessage) || this.chargingStation.isInRejectedState()) {
-      throw new OCPPError(ErrorType.SECURITY_ERROR, 'Cannot send command payload if the charging station is not in accepted state', commandName);
-    } else if (this.chargingStation.isInAcceptedState() || (this.chargingStation.isInPendingState() && params.triggerMessage)) {
-      // eslint-disable-next-line @typescript-eslint/no-this-alias
-      const self = this;
-      // Send a message through wsConnection
-      return Utils.promiseWithTimeout(new Promise((resolve, reject) => {
-        const messageToSend = this.buildMessageToSend(messageId, messageData, messageType, commandName, responseCallback, rejectCallback);
-        if (this.chargingStation.getEnableStatistics()) {
-          this.chargingStation.performanceStatistics.addRequestStatistic(commandName, messageType);
-        }
-        // Check if wsConnection opened
-        if (this.chargingStation.isWebSocketConnectionOpened()) {
-          // Yes: Send Message
-          const beginId = PerformanceStatistics.beginMeasure(commandName);
-          // FIXME: Handle sending error
-          this.chargingStation.wsConnection.send(messageToSend);
-          PerformanceStatistics.endMeasure(commandName, beginId);
-        } else if (!params.skipBufferingOnError) {
-          // Buffer it
-          this.chargingStation.bufferMessage(messageToSend);
-          const ocppError = new OCPPError(ErrorType.GENERIC_ERROR, `WebSocket closed for buffered message id '${messageId}' with content '${messageToSend}'`, messageData?.details ?? {});
-          if (messageType === MessageType.CALL_MESSAGE) {
-            // Reject it but keep the request in the cache
-            return reject(ocppError);
-          }
-          return rejectCallback(ocppError, false);
-        } else {
-          // Reject it
-          return rejectCallback(new OCPPError(ErrorType.GENERIC_ERROR, `WebSocket closed for non buffered message id '${messageId}' with content '${messageToSend}'`, messageData?.details ?? {}), false);
-        }
-        // Response?
-        if (messageType !== MessageType.CALL_MESSAGE) {
-          // Yes: send Ok
-          return resolve(messageData);
-        }
+  public static getInstance<T extends OCPPRequestService>(
+    this: new (ocppResponseService: OCPPResponseService) => T,
+    ocppResponseService: OCPPResponseService
+  ): T {
+    if (OCPPRequestService.instance === null) {
+      OCPPRequestService.instance = new this(ocppResponseService)
+    }
+    return OCPPRequestService.instance as T
+  }
+
+  public async sendResponse (
+    chargingStation: ChargingStation,
+    messageId: string,
+    messagePayload: JsonType,
+    commandName: IncomingRequestCommand
+  ): Promise<ResponseType> {
+    try {
+      // Send response message
+      return await this.internalSendMessage(
+        chargingStation,
+        messageId,
+        messagePayload,
+        MessageType.CALL_RESULT_MESSAGE,
+        commandName
+      )
+    } catch (error) {
+      handleSendMessageError(chargingStation, commandName, error as Error, {
+        throwError: true
+      })
+      return null
+    }
+  }
+
+  public async sendError (
+    chargingStation: ChargingStation,
+    messageId: string,
+    ocppError: OCPPError,
+    commandName: RequestCommand | IncomingRequestCommand
+  ): Promise<ResponseType> {
+    try {
+      // Send error message
+      return await this.internalSendMessage(
+        chargingStation,
+        messageId,
+        ocppError,
+        MessageType.CALL_ERROR_MESSAGE,
+        commandName
+      )
+    } catch (error) {
+      handleSendMessageError(chargingStation, commandName, error as Error)
+      return null
+    }
+  }
+
+  protected async sendMessage (
+    chargingStation: ChargingStation,
+    messageId: string,
+    messagePayload: JsonType,
+    commandName: RequestCommand,
+    params?: RequestParams
+  ): Promise<ResponseType> {
+    params = {
+      ...defaultRequestParams,
+      ...params
+    }
+    try {
+      return await this.internalSendMessage(
+        chargingStation,
+        messageId,
+        messagePayload,
+        MessageType.CALL_MESSAGE,
+        commandName,
+        params
+      )
+    } catch (error) {
+      handleSendMessageError(chargingStation, commandName, error as Error, {
+        throwError: params.throwError
+      })
+      return null
+    }
+  }
 
+  private validateRequestPayload<T extends JsonType>(
+    chargingStation: ChargingStation,
+    commandName: RequestCommand | IncomingRequestCommand,
+    payload: T
+  ): boolean {
+    if (chargingStation.stationInfo?.ocppStrictCompliance === false) {
+      return true
+    }
+    if (!this.payloadValidateFunctions.has(commandName as RequestCommand)) {
+      logger.warn(
+        `${chargingStation.logPrefix()} ${moduleName}.validateRequestPayload: No JSON schema found for command '${commandName}' PDU validation`
+      )
+      return true
+    }
+    const validate = this.payloadValidateFunctions.get(commandName as RequestCommand)
+    payload = clone<T>(payload)
+    OCPPServiceUtils.convertDateToISOString<T>(payload)
+    if (validate?.(payload) === true) {
+      return true
+    }
+    logger.error(
+      `${chargingStation.logPrefix()} ${moduleName}.validateRequestPayload: Command '${commandName}' request PDU is invalid: %j`,
+      validate?.errors
+    )
+    // OCPPError usage here is debatable: it's an error in the OCPP stack but not targeted to sendError().
+    throw new OCPPError(
+      OCPPServiceUtils.ajvErrorsToErrorType(validate?.errors),
+      'Request PDU is invalid',
+      commandName,
+      JSON.stringify(validate?.errors, undefined, 2)
+    )
+  }
 
+  private validateIncomingRequestResponsePayload<T extends JsonType>(
+    chargingStation: ChargingStation,
+    commandName: RequestCommand | IncomingRequestCommand,
+    payload: T
+  ): boolean {
+    if (chargingStation.stationInfo?.ocppStrictCompliance === false) {
+      return true
+    }
+    if (
+      !this.ocppResponseService.incomingRequestResponsePayloadValidateFunctions.has(
+        commandName as IncomingRequestCommand
+      )
+    ) {
+      logger.warn(
+        `${chargingStation.logPrefix()} ${moduleName}.validateIncomingRequestResponsePayload: No JSON schema validation function found for command '${commandName}' PDU validation`
+      )
+      return true
+    }
+    const validate = this.ocppResponseService.incomingRequestResponsePayloadValidateFunctions.get(
+      commandName as IncomingRequestCommand
+    )
+    payload = clone<T>(payload)
+    OCPPServiceUtils.convertDateToISOString<T>(payload)
+    if (validate?.(payload) === true) {
+      return true
+    }
+    logger.error(
+      `${chargingStation.logPrefix()} ${moduleName}.validateIncomingRequestResponsePayload: Command '${commandName}' response PDU is invalid: %j`,
+      validate?.errors
+    )
+    // OCPPError usage here is debatable: it's an error in the OCPP stack but not targeted to sendError().
+    throw new OCPPError(
+      OCPPServiceUtils.ajvErrorsToErrorType(validate?.errors),
+      'Response PDU is invalid',
+      commandName,
+      JSON.stringify(validate?.errors, undefined, 2)
+    )
+  }
+
+  private async internalSendMessage (
+    chargingStation: ChargingStation,
+    messageId: string,
+    messagePayload: JsonType | OCPPError,
+    messageType: MessageType,
+    commandName: RequestCommand | IncomingRequestCommand,
+    params?: RequestParams
+  ): Promise<ResponseType> {
+    params = {
+      ...defaultRequestParams,
+      ...params
+    }
+    if (
+      (chargingStation.inUnknownState() && commandName === RequestCommand.BOOT_NOTIFICATION) ||
+      (chargingStation.stationInfo?.ocppStrictCompliance === false &&
+        chargingStation.inUnknownState()) ||
+      chargingStation.inAcceptedState() ||
+      (chargingStation.inPendingState() &&
+        (params.triggerMessage === true || messageType === MessageType.CALL_RESULT_MESSAGE))
+    ) {
+      // eslint-disable-next-line @typescript-eslint/no-this-alias
+      const self = this
+      // Send a message through wsConnection
+      return await new Promise<ResponseType>((resolve, reject: (reason?: unknown) => void) => {
         /**
          * Function that will receive the request's response
          *
-         * @param payload
-         * @param requestPayload
+         * @param payload -
+         * @param requestPayload -
          */
-        async function responseCallback(payload: Record<string, unknown> | string, requestPayload: Record<string, unknown>): Promise<void> {
-          if (self.chargingStation.getEnableStatistics()) {
-            self.chargingStation.performanceStatistics.addRequestStatistic(commandName, MessageType.CALL_RESULT_MESSAGE);
+        const responseCallback = (payload: JsonType, requestPayload: JsonType): void => {
+          if (chargingStation.stationInfo?.enableStatistics === true) {
+            chargingStation.performanceStatistics?.addRequestStatistic(
+              commandName,
+              MessageType.CALL_RESULT_MESSAGE
+            )
           }
           // Handle the request's response
-          try {
-            await self.ocppResponseService.handleResponse(commandName as RequestCommand, payload, requestPayload);
-            resolve(payload);
-          } catch (error) {
-            reject(error);
-            throw error;
-          } finally {
-            self.chargingStation.requests.delete(messageId);
-          }
+          self.ocppResponseService
+            .responseHandler(
+              chargingStation,
+              commandName as RequestCommand,
+              payload,
+              requestPayload
+            )
+            .then(() => {
+              resolve(payload)
+            })
+            .catch(reject)
+            .finally(() => {
+              chargingStation.requests.delete(messageId)
+              chargingStation.emit(ChargingStationEvents.updated)
+            })
         }
 
         /**
          * Function that will receive the request's error response
          *
-         * @param error
-         * @param requestStatistic
+         * @param ocppError -
+         * @param requestStatistic -
          */
-        function rejectCallback(error: OCPPError, requestStatistic = true): void {
-          if (requestStatistic && self.chargingStation.getEnableStatistics()) {
-            self.chargingStation.performanceStatistics.addRequestStatistic(commandName, MessageType.CALL_ERROR_MESSAGE);
+        const errorCallback = (ocppError: OCPPError, requestStatistic = true): void => {
+          if (requestStatistic && chargingStation.stationInfo?.enableStatistics === true) {
+            chargingStation.performanceStatistics?.addRequestStatistic(
+              commandName,
+              MessageType.CALL_ERROR_MESSAGE
+            )
           }
-          logger.error(`${self.chargingStation.logPrefix()} Error %j occurred when calling command %s with message data %j`, error, commandName, messageData);
-          self.chargingStation.requests.delete(messageId);
-          reject(error);
+          logger.error(
+            `${chargingStation.logPrefix()} Error occurred at ${OCPPServiceUtils.getMessageTypeString(
+              messageType
+            )} command ${commandName} with PDU %j:`,
+            messagePayload,
+            ocppError
+          )
+          chargingStation.requests.delete(messageId)
+          chargingStation.emit(ChargingStationEvents.updated)
+          reject(ocppError)
         }
-      }), Constants.OCPP_WEBSOCKET_TIMEOUT, new OCPPError(ErrorType.GENERIC_ERROR, `Timeout for message id '${messageId}'`, messageData?.details ?? {}), () => {
-        messageType === MessageType.CALL_MESSAGE && this.chargingStation.requests.delete(messageId);
-      });
-    } else {
-      throw new OCPPError(ErrorType.SECURITY_ERROR, 'Cannot send command payload if the charging station is in unknown state', commandName, { status: this.chargingStation?.bootNotificationResponse?.status });
-    }
-  }
 
-  protected handleRequestError(commandName: RequestCommand, error: Error): void {
-    logger.error(this.chargingStation.logPrefix() + ' Request command ' + commandName + ' error: %j', error);
-    throw error;
+        const handleSendError = (ocppError: OCPPError): void => {
+          if (params.skipBufferingOnError === false) {
+            // Buffer
+            chargingStation.bufferMessage(messageToSend)
+            if (messageType === MessageType.CALL_MESSAGE) {
+              this.setCachedRequest(
+                chargingStation,
+                messageId,
+                messagePayload as JsonType,
+                commandName,
+                responseCallback,
+                errorCallback
+              )
+            }
+          } else if (
+            params.skipBufferingOnError === true &&
+            messageType === MessageType.CALL_MESSAGE
+          ) {
+            // Remove request from the cache
+            chargingStation.requests.delete(messageId)
+          }
+          reject(ocppError)
+        }
+
+        if (chargingStation.stationInfo?.enableStatistics === true) {
+          chargingStation.performanceStatistics?.addRequestStatistic(commandName, messageType)
+        }
+        const messageToSend = this.buildMessageToSend(
+          chargingStation,
+          messageId,
+          messagePayload,
+          messageType,
+          commandName
+        )
+        // Check if wsConnection opened
+        if (chargingStation.isWebSocketConnectionOpened()) {
+          const beginId = PerformanceStatistics.beginMeasure(commandName)
+          const sendTimeout = setTimeout(() => {
+            handleSendError(
+              new OCPPError(
+                ErrorType.GENERIC_ERROR,
+                `Timeout ${formatDurationMilliSeconds(
+                  OCPPConstants.OCPP_WEBSOCKET_TIMEOUT
+                )} reached for ${
+                  params.skipBufferingOnError === false ? '' : 'non '
+                }buffered message id '${messageId}' with content '${messageToSend}'`,
+                commandName,
+                (messagePayload as OCPPError).details
+              )
+            )
+          }, OCPPConstants.OCPP_WEBSOCKET_TIMEOUT)
+          chargingStation.wsConnection?.send(messageToSend, (error?: Error) => {
+            PerformanceStatistics.endMeasure(commandName, beginId)
+            clearTimeout(sendTimeout)
+            if (error == null) {
+              logger.debug(
+                `${chargingStation.logPrefix()} >> Command '${commandName}' sent ${OCPPServiceUtils.getMessageTypeString(
+                  messageType
+                )} payload: ${messageToSend}`
+              )
+              if (messageType === MessageType.CALL_MESSAGE) {
+                this.setCachedRequest(
+                  chargingStation,
+                  messageId,
+                  messagePayload as JsonType,
+                  commandName,
+                  responseCallback,
+                  errorCallback
+                )
+              } else {
+                // Resolve response
+                resolve(messagePayload)
+              }
+            } else {
+              handleSendError(
+                new OCPPError(
+                  ErrorType.GENERIC_ERROR,
+                  `WebSocket errored for ${
+                    params.skipBufferingOnError === false ? '' : 'non '
+                  }buffered message id '${messageId}' with content '${messageToSend}'`,
+                  commandName,
+                  { name: error.name, message: error.message, stack: error.stack }
+                )
+              )
+            }
+          })
+        } else {
+          handleSendError(
+            new OCPPError(
+              ErrorType.GENERIC_ERROR,
+              `WebSocket closed for ${
+                params.skipBufferingOnError === false ? '' : 'non '
+              }buffered message id '${messageId}' with content '${messageToSend}'`,
+              commandName,
+              (messagePayload as OCPPError).details
+            )
+          )
+        }
+      })
+    }
+    throw new OCPPError(
+      ErrorType.SECURITY_ERROR,
+      `Cannot send command ${commandName} PDU when the charging station is in ${chargingStation.bootNotificationResponse?.status} state on the central server`,
+      commandName
+    )
   }
 
-  private buildMessageToSend(messageId: string, messageData: Record<string, unknown>, messageType: MessageType, commandName: RequestCommand | IncomingRequestCommand,
-      responseCallback: (payload: Record<string, unknown> | string, requestPayload: Record<string, unknown>) => Promise<void>,
-      rejectCallback: (error: OCPPError, requestStatistic?: boolean) => void): string {
-    let messageToSend: string;
+  private buildMessageToSend (
+    chargingStation: ChargingStation,
+    messageId: string,
+    messagePayload: JsonType | OCPPError,
+    messageType: MessageType,
+    commandName: RequestCommand | IncomingRequestCommand
+  ): string {
+    let messageToSend: string
     // Type of message
     switch (messageType) {
       // Request
       case MessageType.CALL_MESSAGE:
         // Build request
-        this.chargingStation.requests.set(messageId, [responseCallback, rejectCallback, commandName, messageData]);
-        messageToSend = JSON.stringify([messageType, messageId, commandName, messageData]);
-        break;
+        this.validateRequestPayload(chargingStation, commandName, messagePayload as JsonType)
+        messageToSend = JSON.stringify([
+          messageType,
+          messageId,
+          commandName as RequestCommand,
+          messagePayload as JsonType
+        ] satisfies OutgoingRequest)
+        break
       // Response
       case MessageType.CALL_RESULT_MESSAGE:
         // Build response
-        messageToSend = JSON.stringify([messageType, messageId, messageData]);
-        break;
+        this.validateIncomingRequestResponsePayload(
+          chargingStation,
+          commandName,
+          messagePayload as JsonType
+        )
+        messageToSend = JSON.stringify([
+          messageType,
+          messageId,
+          messagePayload as JsonType
+        ] satisfies Response)
+        break
       // Error Message
       case MessageType.CALL_ERROR_MESSAGE:
         // Build Error Message
-        messageToSend = JSON.stringify([messageType, messageId, messageData?.code ?? ErrorType.GENERIC_ERROR, messageData?.message ?? '', messageData?.details ?? {}]);
-        break;
+        messageToSend = JSON.stringify([
+          messageType,
+          messageId,
+          (messagePayload as OCPPError).code,
+          (messagePayload as OCPPError).message,
+          (messagePayload as OCPPError).details ?? {
+            command: (messagePayload as OCPPError).command
+          }
+        ] satisfies ErrorResponse)
+        break
     }
-    return messageToSend;
+    return messageToSend
+  }
+
+  private setCachedRequest (
+    chargingStation: ChargingStation,
+    messageId: string,
+    messagePayload: JsonType,
+    commandName: RequestCommand | IncomingRequestCommand,
+    responseCallback: ResponseCallback,
+    errorCallback: ErrorCallback
+  ): void {
+    chargingStation.requests.set(messageId, [
+      responseCallback,
+      errorCallback,
+      commandName,
+      messagePayload
+    ])
   }
 
-  public abstract sendHeartbeat(params?: SendParams): Promise<void>;
-  public abstract sendBootNotification(chargePointModel: string, chargePointVendor: string, chargeBoxSerialNumber?: string, firmwareVersion?: string, chargePointSerialNumber?: string, iccid?: string, imsi?: string, meterSerialNumber?: string, meterType?: string, params?: SendParams): Promise<BootNotificationResponse>;
-  public abstract sendStatusNotification(connectorId: number, status: ChargePointStatus, errorCode?: ChargePointErrorCode): Promise<void>;
-  public abstract sendAuthorize(connectorId: number, idTag?: string): Promise<AuthorizeResponse>;
-  public abstract sendStartTransaction(connectorId: number, idTag?: string): Promise<StartTransactionResponse>;
-  public abstract sendStopTransaction(transactionId: number, meterStop: number, idTag?: string, reason?: StopTransactionReason): Promise<StopTransactionResponse>;
-  public abstract sendMeterValues(connectorId: number, transactionId: number, interval: number): Promise<void>;
-  public abstract sendTransactionBeginMeterValues(connectorId: number, transactionId: number, beginMeterValue: MeterValue): Promise<void>;
-  public abstract sendTransactionEndMeterValues(connectorId: number, transactionId: number, endMeterValue: MeterValue): Promise<void>;
-  public abstract sendDiagnosticsStatusNotification(diagnosticsStatus: DiagnosticsStatus): Promise<void>;
-  public abstract sendResult(messageId: string, resultMessageData: Record<string, unknown>, commandName: RequestCommand | IncomingRequestCommand): Promise<unknown>;
-  public abstract sendError(messageId: string, error: OCPPError, commandName: RequestCommand | IncomingRequestCommand): Promise<unknown>;
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  public abstract requestHandler<ReqType extends JsonType, ResType extends JsonType>(
+    chargingStation: ChargingStation,
+    commandName: RequestCommand,
+    // FIXME: should be ReqType
+    commandParams?: JsonType,
+    params?: RequestParams
+  ): Promise<ResType>
 }