从 NodeJS/ExpressJS 中的中间件内部调用中间件

Calling a middleware from within a middleware in NodeJS/ExpressJS

我已经创建了一些带有一些逻辑的标准中间件,并且根据逻辑我需要调用一些第 3 方中间件。

使用 app.use() 添加中间件,这是我添加自定义中间件的地方。

进入我的中间件后,我无法再访问 app.use(),我该如何调用中间件?

这是一些代码:

有什么想法吗?

const customerData = (req, res, next) => {
  try {
    console.log('Started');
    if (process.env.STORE_CUSTOMER_DATA === 'true') {

        // Here is some custom middleware that doesn't belong to me
        //
        // Returns a function (I confirmed it) ready to be called with res,req, next
        //
        let externalMiddlware = logger({
          custom:true
        });

// Do I return it ? Call it ? Trying everything and nothing seems to work

        externalMiddlware(req,res,next);  // ???
    } else {

      // DO not call external middleware, will break out of if and then call next()
    }
    console.log('Finished');
    next();
  } catch (err) {
    next(err);
  }
};

module.exports = customerData;

我认为这应该可行,但如果您将回调委托给另一个 externalMiddlware,则不应在 customerData 中调用 next() 使用此第三个中间件

那你试过了吗

const customerData = (req, res, next) => {
  try {
    console.log('Started');
    if (process.env.STORE_CUSTOMER_DATA === 'true') {
        let externalMiddlware = logger({
          custom:true
        });
        return externalMiddlware(req,res,next); 
    } else {
        return next(); // <= next moved
    }
  } catch (err) {
    next(err);
  }
};

module.exports = customerData;