src/charging-station/ui-server/ui-services/AbstractUIService.ts

   1 import { RawData } from 'ws';
   2
   3 import BaseError from '../../../exception/BaseError';
   4 import { JsonType } from '../../../types/JsonType';
   5 import {
   6   ProcedureName,
   7   ProtocolRequest,
   8   ProtocolRequestHandler,
   9   ProtocolResponse,
  10   ProtocolVersion,
  11   RequestPayload,
  12   ResponsePayload,
  13   ResponseStatus,
  14 } from '../../../types/UIProtocol';
  15 import logger from '../../../utils/Logger';
  16 import Utils from '../../../utils/Utils';
  17 import Bootstrap from '../../Bootstrap';
  18 import WorkerBroadcastChannel from '../../WorkerBroadcastChannel';
  19 import { AbstractUIServer } from '../AbstractUIServer';
  20
  21 const moduleName = 'AbstractUIService';
  22
  23 export default abstract class AbstractUIService {
  24   protected readonly version: ProtocolVersion;
  25   protected readonly uiServer: AbstractUIServer;
  26   protected readonly messageHandlers: Map<ProcedureName, ProtocolRequestHandler>;
  27   protected workerBroadcastChannel: WorkerBroadcastChannel;
  28
  29   constructor(uiServer: AbstractUIServer, version: ProtocolVersion) {
  30     this.version = version;
  31     this.uiServer = uiServer;
  32     this.messageHandlers = new Map<ProcedureName, ProtocolRequestHandler>([
  33       [ProcedureName.LIST_CHARGING_STATIONS, this.handleListChargingStations.bind(this)],
  34       [ProcedureName.START_SIMULATOR, this.handleStartSimulator.bind(this)],
  35       [ProcedureName.STOP_SIMULATOR, this.handleStopSimulator.bind(this)],
  36     ]);
  37     this.workerBroadcastChannel = new WorkerBroadcastChannel();
  38   }
  39
  40   public async messageHandler(request: RawData): Promise<void> {
  41     let messageId: string;
  42     let command: ProcedureName;
  43     let requestPayload: RequestPayload;
  44     let responsePayload: ResponsePayload;
  45     try {
  46       [messageId, command, requestPayload] = this.dataValidation(request);
  47
  48       if (this.messageHandlers.has(command) === false) {
  49         throw new BaseError(
  50           `${command} is not implemented to handle message payload ${JSON.stringify(
  51             requestPayload,
  52             null,
  53             2
  54           )}`
  55         );
  56       }
  57
  58       // Call the message handler to build the response payload
  59       responsePayload = await this.messageHandlers.get(command)(requestPayload);
  60     } catch (error) {
  61       // Log
  62       logger.error(
  63         `${this.uiServer.logPrefix(moduleName, 'messageHandler')} Handle message error:`,
  64         error
  65       );
  66       // Send the message response failure
  67       this.uiServer.sendResponse(
  68         this.buildProtocolResponse(messageId ?? 'error', {
  69           status: ResponseStatus.FAILURE,
  70           command,
  71           requestPayload,
  72           errorMessage: (error as Error).message,
  73           errorStack: (error as Error).stack,
  74         })
  75       );
  76       throw error;
  77     }
  78
  79     // Send the message response success
  80     this.uiServer.sendResponse(this.buildProtocolResponse(messageId, responsePayload));
  81   }
  82
  83   protected buildProtocolResponse(messageId: string, payload: ResponsePayload): string {
  84     return JSON.stringify([messageId, payload] as ProtocolResponse);
  85   }
  86
  87   // Validate the raw data received from the WebSocket
  88   // TODO: should probably be moved to the ws verify clients callback
  89   private dataValidation(rawData: RawData): ProtocolRequest {
  90     logger.debug(
  91       `${this.uiServer.logPrefix(
  92         moduleName,
  93         'dataValidation'
  94       )} Raw data received: ${rawData.toString()}`
  95     );
  96     const data = JSON.parse(rawData.toString()) as JsonType[];
  97
  98     if (Utils.isIterable(data) === false) {
  99       throw new BaseError('UI protocol request is not iterable');
 100     }
 101
 102     if (data.length !== 3) {
 103       throw new BaseError('UI protocol request is malformed');
 104     }
 105
 106     return data as ProtocolRequest;
 107   }
 108
 109   private handleListChargingStations(): ResponsePayload {
 110     // TODO: remove cast to unknown
 111     return {
 112       status: ResponseStatus.SUCCESS,
 113       ...Array.from(this.uiServer.chargingStations.values()),
 114     } as unknown as ResponsePayload;
 115   }
 116
 117   private async handleStartSimulator(): Promise<ResponsePayload> {
 118     await Bootstrap.getInstance().start();
 119     return { status: ResponseStatus.SUCCESS };
 120   }
 121
 122   private async handleStopSimulator(): Promise<ResponsePayload> {
 123     await Bootstrap.getInstance().stop();
 124     return { status: ResponseStatus.SUCCESS };
 125   }
 126 }