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

   1 import { ProtocolCommand, ProtocolRequestHandler } from '../../types/UIProtocol';
   2
   3 import BaseError from '../../exception/BaseError';
   4 import { JsonType } from '../../types/JsonType';
   5 import UIWebSocketServer from '../UIWebSocketServer';
   6 import logger from '../../utils/Logger';
   7
   8 export default abstract class AbstractUIService {
   9   protected readonly uiWebSocketServer: UIWebSocketServer;
  10   protected readonly messageHandlers: Map<ProtocolCommand, ProtocolRequestHandler>;
  11
  12   constructor(uiWebSocketServer: UIWebSocketServer) {
  13     this.uiWebSocketServer = uiWebSocketServer;
  14     this.messageHandlers = new Map<ProtocolCommand, ProtocolRequestHandler>([
  15       [ProtocolCommand.LIST_CHARGING_STATIONS, this.handleListChargingStations.bind(this)],
  16     ]);
  17   }
  18
  19   public async handleMessage(command: ProtocolCommand, payload: JsonType): Promise<void> {
  20     let messageResponse: JsonType;
  21     if (this.messageHandlers.has(command)) {
  22       try {
  23         // Call the method to build the message response
  24         messageResponse = (await this.messageHandlers.get(command)(payload)) as JsonType;
  25       } catch (error) {
  26         // Log
  27         logger.error(this.uiWebSocketServer.logPrefix() + ' Handle message error: %j', error);
  28         throw error;
  29       }
  30     } else {
  31       // Throw exception
  32       throw new BaseError(
  33         `${command} is not implemented to handle message payload ${JSON.stringify(
  34           payload,
  35           null,
  36           2
  37         )}`
  38       );
  39     }
  40     // Send the built message response
  41     this.uiWebSocketServer.broadcastToClients(this.buildProtocolMessage(command, messageResponse));
  42   }
  43
  44   protected buildProtocolMessage(command: ProtocolCommand, payload: JsonType): string {
  45     return JSON.stringify([command, payload]);
  46   }
  47
  48   private handleListChargingStations(): Set<string> {
  49     return this.uiWebSocketServer.chargingStations;
  50   }
  51 }