TypeScript Container.get方法代碼示例

/**
 * Get controller instance from container or instantiate one
 *
 * @param {any} Controller
 *
 * @returns {ExpressClass}
 */
function getController(Controller: Type): ExpressClass {
  try {
    return Container.get(Controller);
  } catch {
    return new Controller();
  }
}

  return function(...args: any[]): any {
    const next: NextFunction = args[args.length - 1];
    let instance: Middleware | ServerMiddleware | Type;

    try {
      instance = Container.get(middleware);
    } catch {
      try {
        instance = new (middleware as Type)();
      } catch {
        instance = middleware as any;
      }
    }

    // first, assuming that middleware is a class, try to use it,
    // otherwise use it as a function
    const use = (instance as Middleware | ServerMiddleware).use ?
      (instance as Middleware | ServerMiddleware).use : instance as Type;

    try {
      const result = use.apply(instance, args);

       // if result of execution is a promise, add additional listener to catch error
      if (result instanceof Promise) {
        result.catch(next);
      }

      return result;
    } catch (e) {
      return next(e);
    }

  }

/**
 * Attach Controller
 *
 * @param {SocketIO.Server} IO
 * @param {Type} Controller
 */
function attachController(
  io: SocketIO.Server,
  controller: Type
) {
  const instance: SocketClass = Container.get(controller);
  const meta: SocketMeta = getMeta(instance);
  const ioNS: SocketIO.Namespace = io.of(meta.namespace);

  /**
   * Apply io based events
   */
  applyEvents(io, null, controller, EventType.IO);

  /**
   * Apply local listeners (socket based)
   */
  ioNS.on('connection', (socket: SocketIO.Socket) => {
    /**
     * Apply all registered controller-based and event-based middlewares to socket
     */
    (socket as any).use(socketMiddlewareHandler(io, socket, meta));

    /**
     * Apply socket based events
     */
    applyEvents(io, socket, controller, EventType.Socket);
  });
}

/**
 * Instantiate middleware and invoke it with arguments
 *
 * @param {InjectionToken | Type} middleware
 * @param {any[]} args
 */
function getMiddleware(middleware: InjectionToken | Type, args: any[]) {
  const next: NextFunction = args[args.length - 1]; // last parameter is always the next function
  let instance;

  try {
    // first, trying to get instance from the container
    instance = Container.get(middleware);
  } catch {
    try {
      // if container fails, trying to instantiate it
      instance = new (middleware as Type)();
    } catch {
      // if instantiation fails, try to use it as is
      instance = middleware as any;
    }
  }

  // first, assuming that middleware is a class, try to use it,
  // otherwise use it as a function
  const result = instance.use ?
    (instance as Middleware | ErrorMiddleware).use.apply(instance, args) :
    (instance as Type).apply(instance, args);

  // if result of execution is a promise, add additional listener to catch error
  if (result instanceof Promise) {
    result.catch(e => next(e));
  }

  return result
}

/**
 * Apply listeners to socket or io
 *
 * @param {SocketIO.Server|SocketIO.Namespace} io
 * @param {SocketIO.Socket} socket
 * @param {Type} controller
 * @param {EventType} type
 */
function applyEvents(
  io: SocketIO.Server | SocketIO.Namespace,
  socket: SocketIO.Socket,
  controller: Type,
  type: EventType
) {
  const instance: SocketClass = Container.get(controller);
  const meta: SocketMeta = getMeta(instance);
  const ioSock: any = socket || io;

  meta.listeners
    .filter((listener: Listener) => listener.type === type)
    .forEach((listener: Listener) => ioSock.on(listener.event, (...args) => {
      const methodName: string = listener.methodName;
      const newArgs: any[] = mapArguments(
        io, socket || args[0], meta.params[methodName], args
      );

      return instance[methodName].apply(instance, newArgs);
    }));
}