BasicFDC3Server.ts

import { FDC3Server } from './FDC3Server';
import { AppRegistration, InstanceID, ServerContext } from './ServerContext';
import { BroadcastHandler, ChannelState } from './handlers/BroadcastHandler';
import { IntentHandler } from './handlers/IntentHandler';
import { Directory } from './directory/DirectoryInterface';
import { OpenHandler } from './handlers/OpenHandler';
import { BrowserTypes } from '@kite9/fdc3-schema';
import { HeartbeatHandler } from './handlers/HeartbeatHandler';

type AppRequestMessage = BrowserTypes.AppRequestMessage;
type WebConnectionProtocol4ValidateAppIdentity = BrowserTypes.WebConnectionProtocol4ValidateAppIdentity;

export interface MessageHandler {
  /**
   * Handles an AgentRequestMessage from the messaging source
   */
  accept(msg: any, sc: ServerContext<AppRegistration>, from: InstanceID): void;

  shutdown(): void;
}

/**
 * This defers all functionality to either MessageHandler's or the ServerContext objects.
 */
export class BasicFDC3Server implements FDC3Server {
  readonly handlers: MessageHandler[];
  private sc: ServerContext<AppRegistration>;

  constructor(handlers: MessageHandler[], sc: ServerContext<AppRegistration>) {
    this.handlers = handlers;
    this.sc = sc;
  }

  receive(message: AppRequestMessage | WebConnectionProtocol4ValidateAppIdentity, from: InstanceID): void {
    this.handlers.forEach(h => h.accept(message, this.sc, from));
  }

  shutdown(): void {
    this.handlers.forEach(h => h.shutdown());
  }
}

export class DefaultFDC3Server extends BasicFDC3Server {
  constructor(
    sc: ServerContext<AppRegistration>,
    directory: Directory,
    userChannels: ChannelState[],
    heartbeats: boolean,
    intentTimeoutMs: number = 20000,
    openHandlerTimeoutMs: number = 10000
  ) {
    const handlers: MessageHandler[] = [
      new BroadcastHandler(userChannels),
      new IntentHandler(directory, intentTimeoutMs),
      new OpenHandler(directory, openHandlerTimeoutMs),
    ];

    if (heartbeats) {
      handlers.push(new HeartbeatHandler(openHandlerTimeoutMs / 10, openHandlerTimeoutMs / 2, openHandlerTimeoutMs));
    }

    super(handlers, sc);
  }
}