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

   1 import { ProtocolCommand, ProtocolRequestHandler } from '../../types/UIProtocol';
   2
   3 import BaseError from '../../exception/BaseError';
   4 import UIWebSocketServer from '../UIWebSocketServer';
   5 import logger from '../../utils/Logger';
   6
   7 export default abstract class AbstractUIService {
   8   protected readonly uiWebSocketServer: UIWebSocketServer;
   9   protected readonly messageHandlers: Map<ProtocolCommand, ProtocolRequestHandler>;
  10
  11   constructor(uiWebSocketServer: UIWebSocketServer) {
  12     this.uiWebSocketServer = uiWebSocketServer;
  13     this.messageHandlers = new Map<ProtocolCommand, ProtocolRequestHandler>([
  14       [ProtocolCommand.LIST_CHARGING_STATIONS, this.handleListChargingStations.bind(this)],
  15     ]);
  16   }
  17
  18   public async handleMessage(command: ProtocolCommand, payload: Record<string, unknown>): Promise<void> {
  19     let messageResponse: Record<string, unknown>;
  20     if (this.messageHandlers.has(command)) {
  21       try {
  22         // Call the method to build the message response
  23         messageResponse = await this.messageHandlers.get(command)(payload) as Record<string, unknown>;
  24       } catch (error) {
  25         // Log
  26         logger.error(this.uiWebSocketServer.logPrefix() + ' Handle message error: %j', error);
  27         throw error;
  28       }
  29     } else {
  30       // Throw exception
  31       throw new BaseError(`${command} is not implemented to handle message payload ${JSON.stringify(payload, null, 2)}`);
  32     }
  33     // Send the built message response
  34     this.uiWebSocketServer.broadcastToClients(this.buildProtocolMessage(command, messageResponse));
  35   }
  36
  37   protected buildProtocolMessage(
  38       command: ProtocolCommand,
  39       payload: Record<string, unknown>,
  40   ): string {
  41     return JSON.stringify([command, payload]);
  42   }
  43
  44   private handleListChargingStations(): Set<string> {
  45     return this.uiWebSocketServer.chargingStations;
  46   }
  47 }