src/charging-station/ocpp/OCPPRequestService.ts

   1 import type { JSONSchemaType } from 'ajv';
   2 import Ajv from 'ajv-draft-04';
   3 import ajvFormats from 'ajv-formats';
   4
   5 import OCPPError from '../../exception/OCPPError';
   6 import PerformanceStatistics from '../../performance/PerformanceStatistics';
   7 import type { EmptyObject } from '../../types/EmptyObject';
   8 import type { HandleErrorParams } from '../../types/Error';
   9 import type { JsonObject, JsonType } from '../../types/JsonType';
  10 import { ErrorType } from '../../types/ocpp/ErrorType';
  11 import { MessageType } from '../../types/ocpp/MessageType';
  12 import {
  13   IncomingRequestCommand,
  14   OutgoingRequest,
  15   RequestCommand,
  16   RequestParams,
  17   ResponseType,
  18 } from '../../types/ocpp/Requests';
  19 import type { ErrorResponse, Response } from '../../types/ocpp/Responses';
  20 import Constants from '../../utils/Constants';
  21 import logger from '../../utils/Logger';
  22 import Utils from '../../utils/Utils';
  23 import type ChargingStation from '../ChargingStation';
  24 import type OCPPResponseService from './OCPPResponseService';
  25 import { OCPPServiceUtils } from './OCPPServiceUtils';
  26
  27 const moduleName = 'OCPPRequestService';
  28
  29 export default abstract class OCPPRequestService {
  30   private static instance: OCPPRequestService | null = null;
  31   private readonly ajv: Ajv;
  32
  33   private readonly ocppResponseService: OCPPResponseService;
  34
  35   protected constructor(ocppResponseService: OCPPResponseService) {
  36     this.ocppResponseService = ocppResponseService;
  37     this.ajv = new Ajv();
  38     ajvFormats(this.ajv);
  39     this.requestHandler.bind(this);
  40     this.sendMessage.bind(this);
  41     this.sendResponse.bind(this);
  42     this.sendError.bind(this);
  43     this.internalSendMessage.bind(this);
  44     this.buildMessageToSend.bind(this);
  45     this.validateRequestPayload.bind(this);
  46   }
  47
  48   public static getInstance<T extends OCPPRequestService>(
  49     this: new (ocppResponseService: OCPPResponseService) => T,
  50     ocppResponseService: OCPPResponseService
  51   ): T {
  52     if (OCPPRequestService.instance === null) {
  53       OCPPRequestService.instance = new this(ocppResponseService);
  54     }
  55     return OCPPRequestService.instance as T;
  56   }
  57
  58   public async sendResponse(
  59     chargingStation: ChargingStation,
  60     messageId: string,
  61     messagePayload: JsonType,
  62     commandName: IncomingRequestCommand
  63   ): Promise<ResponseType> {
  64     try {
  65       // Send response message
  66       return await this.internalSendMessage(
  67         chargingStation,
  68         messageId,
  69         messagePayload,
  70         MessageType.CALL_RESULT_MESSAGE,
  71         commandName
  72       );
  73     } catch (error) {
  74       this.handleSendMessageError(chargingStation, commandName, error as Error, {
  75         throwError: true,
  76       });
  77     }
  78   }
  79
  80   public async sendError(
  81     chargingStation: ChargingStation,
  82     messageId: string,
  83     ocppError: OCPPError,
  84     commandName: RequestCommand | IncomingRequestCommand
  85   ): Promise<ResponseType> {
  86     try {
  87       // Send error message
  88       return await this.internalSendMessage(
  89         chargingStation,
  90         messageId,
  91         ocppError,
  92         MessageType.CALL_ERROR_MESSAGE,
  93         commandName
  94       );
  95     } catch (error) {
  96       this.handleSendMessageError(chargingStation, commandName, error as Error);
  97     }
  98   }
  99
 100   protected async sendMessage(
 101     chargingStation: ChargingStation,
 102     messageId: string,
 103     messagePayload: JsonType,
 104     commandName: RequestCommand,
 105     params: RequestParams = {
 106       skipBufferingOnError: false,
 107       triggerMessage: false,
 108     }
 109   ): Promise<ResponseType> {
 110     try {
 111       return await this.internalSendMessage(
 112         chargingStation,
 113         messageId,
 114         messagePayload,
 115         MessageType.CALL_MESSAGE,
 116         commandName,
 117         params
 118       );
 119     } catch (error) {
 120       this.handleSendMessageError(chargingStation, commandName, error as Error);
 121     }
 122   }
 123
 124   protected validateRequestPayload<T extends JsonType>(
 125     chargingStation: ChargingStation,
 126     commandName: RequestCommand,
 127     schema: JSONSchemaType<T>,
 128     payload: T
 129   ): boolean {
 130     if (chargingStation.getPayloadSchemaValidation() === false) {
 131       return true;
 132     }
 133     const validate = this.ajv.compile(schema);
 134     if (validate(payload)) {
 135       return true;
 136     }
 137     logger.error(
 138       `${chargingStation.logPrefix()} ${moduleName}.validateRequestPayload: Request PDU is invalid: %j`,
 139       validate.errors
 140     );
 141     // OCPPError usage here is debatable: it's an error in the OCPP stack but not targeted to sendError().
 142     throw new OCPPError(
 143       OCPPServiceUtils.ajvErrorsToErrorType(validate.errors),
 144       'Request PDU is invalid',
 145       commandName,
 146       JSON.stringify(validate.errors, null, 2)
 147     );
 148   }
 149
 150   private async internalSendMessage(
 151     chargingStation: ChargingStation,
 152     messageId: string,
 153     messagePayload: JsonType | OCPPError,
 154     messageType: MessageType,
 155     commandName?: RequestCommand | IncomingRequestCommand,
 156     params: RequestParams = {
 157       skipBufferingOnError: false,
 158       triggerMessage: false,
 159     }
 160   ): Promise<ResponseType> {
 161     if (
 162       (chargingStation.isInUnknownState() === true &&
 163         commandName === RequestCommand.BOOT_NOTIFICATION) ||
 164       (chargingStation.getOcppStrictCompliance() === false &&
 165         chargingStation.isInUnknownState() === true) ||
 166       chargingStation.isInAcceptedState() === true ||
 167       (chargingStation.isInPendingState() === true &&
 168         (params.triggerMessage === true || messageType === MessageType.CALL_RESULT_MESSAGE))
 169     ) {
 170       // eslint-disable-next-line @typescript-eslint/no-this-alias
 171       const self = this;
 172       // Send a message through wsConnection
 173       return Utils.promiseWithTimeout(
 174         new Promise((resolve, reject) => {
 175           const messageToSend = this.buildMessageToSend(
 176             chargingStation,
 177             messageId,
 178             messagePayload,
 179             messageType,
 180             commandName,
 181             responseCallback,
 182             errorCallback
 183           );
 184           if (chargingStation.getEnableStatistics() === true) {
 185             chargingStation.performanceStatistics.addRequestStatistic(commandName, messageType);
 186           }
 187           // Check if wsConnection opened
 188           if (chargingStation.isWebSocketConnectionOpened() === true) {
 189             // Yes: Send Message
 190             const beginId = PerformanceStatistics.beginMeasure(commandName);
 191             // FIXME: Handle sending error
 192             chargingStation.wsConnection.send(messageToSend);
 193             PerformanceStatistics.endMeasure(commandName, beginId);
 194             logger.debug(
 195               `${chargingStation.logPrefix()} >> Command '${commandName}' sent ${this.getMessageTypeString(
 196                 messageType
 197               )} payload: ${messageToSend}`
 198             );
 199           } else if (params.skipBufferingOnError === false) {
 200             // Buffer it
 201             chargingStation.bufferMessage(messageToSend);
 202             const ocppError = new OCPPError(
 203               ErrorType.GENERIC_ERROR,
 204               `WebSocket closed for buffered message id '${messageId}' with content '${messageToSend}'`,
 205               commandName,
 206               (messagePayload as JsonObject)?.details ?? {}
 207             );
 208             if (messageType === MessageType.CALL_MESSAGE) {
 209               // Reject it but keep the request in the cache
 210               return reject(ocppError);
 211             }
 212             return errorCallback(ocppError, false);
 213           } else {
 214             // Reject it
 215             return errorCallback(
 216               new OCPPError(
 217                 ErrorType.GENERIC_ERROR,
 218                 `WebSocket closed for non buffered message id '${messageId}' with content '${messageToSend}'`,
 219                 commandName,
 220                 (messagePayload as JsonObject)?.details ?? {}
 221               ),
 222               false
 223             );
 224           }
 225           // Response?
 226           if (messageType !== MessageType.CALL_MESSAGE) {
 227             // Yes: send Ok
 228             return resolve(messagePayload);
 229           }
 230
 231           /**
 232            * Function that will receive the request's response
 233            *
 234            * @param payload
 235            * @param requestPayload
 236            */
 237           async function responseCallback(
 238             payload: JsonType,
 239             requestPayload: JsonType
 240           ): Promise<void> {
 241             if (chargingStation.getEnableStatistics() === true) {
 242               chargingStation.performanceStatistics.addRequestStatistic(
 243                 commandName,
 244                 MessageType.CALL_RESULT_MESSAGE
 245               );
 246             }
 247             // Handle the request's response
 248             try {
 249               await self.ocppResponseService.responseHandler(
 250                 chargingStation,
 251                 commandName as RequestCommand,
 252                 payload,
 253                 requestPayload
 254               );
 255               resolve(payload);
 256             } catch (error) {
 257               reject(error);
 258             } finally {
 259               chargingStation.requests.delete(messageId);
 260             }
 261           }
 262
 263           /**
 264            * Function that will receive the request's error response
 265            *
 266            * @param error
 267            * @param requestStatistic
 268            */
 269           function errorCallback(error: OCPPError, requestStatistic = true): void {
 270             if (requestStatistic === true && chargingStation.getEnableStatistics() === true) {
 271               chargingStation.performanceStatistics.addRequestStatistic(
 272                 commandName,
 273                 MessageType.CALL_ERROR_MESSAGE
 274               );
 275             }
 276             logger.error(
 277               `${chargingStation.logPrefix()} Error occurred when calling command ${commandName} with message data ${JSON.stringify(
 278                 messagePayload
 279               )}:`,
 280               error
 281             );
 282             chargingStation.requests.delete(messageId);
 283             reject(error);
 284           }
 285         }),
 286         Constants.OCPP_WEBSOCKET_TIMEOUT,
 287         new OCPPError(
 288           ErrorType.GENERIC_ERROR,
 289           `Timeout for message id '${messageId}'`,
 290           commandName,
 291           (messagePayload as JsonObject)?.details ?? {}
 292         ),
 293         () => {
 294           messageType === MessageType.CALL_MESSAGE && chargingStation.requests.delete(messageId);
 295         }
 296       );
 297     }
 298     throw new OCPPError(
 299       ErrorType.SECURITY_ERROR,
 300       `Cannot send command ${commandName} PDU when the charging station is in ${chargingStation.getRegistrationStatus()} state on the central server`,
 301       commandName
 302     );
 303   }
 304
 305   private buildMessageToSend(
 306     chargingStation: ChargingStation,
 307     messageId: string,
 308     messagePayload: JsonType | OCPPError,
 309     messageType: MessageType,
 310     commandName?: RequestCommand | IncomingRequestCommand,
 311     responseCallback?: (payload: JsonType, requestPayload: JsonType) => Promise<void>,
 312     errorCallback?: (error: OCPPError, requestStatistic?: boolean) => void
 313   ): string {
 314     let messageToSend: string;
 315     // Type of message
 316     switch (messageType) {
 317       // Request
 318       case MessageType.CALL_MESSAGE:
 319         // Build request
 320         chargingStation.requests.set(messageId, [
 321           responseCallback,
 322           errorCallback,
 323           commandName,
 324           messagePayload as JsonType,
 325         ]);
 326         messageToSend = JSON.stringify([
 327           messageType,
 328           messageId,
 329           commandName,
 330           messagePayload,
 331         ] as OutgoingRequest);
 332         break;
 333       // Response
 334       case MessageType.CALL_RESULT_MESSAGE:
 335         // Build response
 336         messageToSend = JSON.stringify([messageType, messageId, messagePayload] as Response);
 337         break;
 338       // Error Message
 339       case MessageType.CALL_ERROR_MESSAGE:
 340         // Build Error Message
 341         messageToSend = JSON.stringify([
 342           messageType,
 343           messageId,
 344           (messagePayload as OCPPError)?.code ?? ErrorType.GENERIC_ERROR,
 345           (messagePayload as OCPPError)?.message ?? '',
 346           (messagePayload as OCPPError)?.details ?? { commandName },
 347         ] as ErrorResponse);
 348         break;
 349     }
 350     return messageToSend;
 351   }
 352
 353   private getMessageTypeString(messageType: MessageType): string {
 354     switch (messageType) {
 355       case MessageType.CALL_MESSAGE:
 356         return 'request';
 357       case MessageType.CALL_RESULT_MESSAGE:
 358         return 'response';
 359       case MessageType.CALL_ERROR_MESSAGE:
 360         return 'error';
 361     }
 362   }
 363
 364   private handleSendMessageError(
 365     chargingStation: ChargingStation,
 366     commandName: RequestCommand | IncomingRequestCommand,
 367     error: Error,
 368     params: HandleErrorParams<EmptyObject> = { throwError: false }
 369   ): void {
 370     logger.error(`${chargingStation.logPrefix()} Request command '${commandName}' error:`, error);
 371     if (params?.throwError === true) {
 372       throw error;
 373     }
 374   }
 375
 376   // eslint-disable-next-line @typescript-eslint/no-unused-vars
 377   public abstract requestHandler<RequestType extends JsonType, ResponseType extends JsonType>(
 378     chargingStation: ChargingStation,
 379     commandName: RequestCommand,
 380     commandParams?: JsonType,
 381     params?: RequestParams
 382   ): Promise<ResponseType>;
 383 }