如何在快速Router.route和控制器模式中触发next（）？

Question

在请求到达我的api路由之一后，我似乎无法弄清楚如何实现“ next（）”。 我想在所有步骤完成后而不是在api路由之前进行日志记录。 我已经在路由上实现了控制器模式。 我现在只能记录错误信息，但是我想记录所有请求：

//------ api/index.js
import routes from './routes/index.route';

app.use('/api', routes);


// ??? HOW TO HANDLE next() called in "/api routes"
// only handles incoming requests not found in "/api routes"
app.use((req, res, next) => {
  // logic here...
  next(error);
});


// global error handler
app.use((error, req, res, next) => {
  // logging logic here...
});



//------ routes/index.route.js
import express from 'express';
import userRoutes from './user.route';
import bookRoutes from './book.route';

const router = express.Router();

router.use('/user', userRoutes);
router.use('/book', bookRoutes);



//------ routes/book.route.js
import express from 'express';
import bookCtrl from './../controllers/book.controller';

const router = express.Router();
router.route('/:bookId').get(bookCtrl.getBook);




//------ controllers/book.controller.js
export const getBook = async (req, res, next) => {
  const book = // get book logic here;

  return res.status(httpStatus.OK).json(book);

  // HOW DO I TRIGGER next()?  
  // I tried this approach as well: 

  // res.status(httpStatus.OK).json(book);
  // next();

  //however, it would say, "Error: Can't set headers after they are sent."
}

非常感谢。

Answer 1

只需更换

 return res.status(httpStatus.OK).json(book);
 // HOW DO I TRIGGER next()? 

同

res.status(httpStatus.OK).json(book);
next();

它将起作用。

Answer 2

我想出了一种触发下一个的方法，该方法不是立即发送响应，而是将其分配给res.locals并调用next。 这是根据我上面的代码所做的更改：

//------ api/index.js
// handle next() event coming from "/api routes"
// and also handles incoming requests not found in "/api routes"
app.use((req, res, next) => {
  if (res.locals.status) {
    const { status, responseData } = res.locals;
    res.status(status).json(responseData);
    // logging logic here...
  } else {
    // error logic here...
    // forward this error into the global error handler
    next(error);
  }
});



// controllers/book.controller.js
export const getBook = async (req, res, next) => {
  // get book logic here..
  const book = // get book logic here;

    res.locals = {
      status: httpStatus.OK,
      responseData: {
        book,
      },
    };

    next();
}

感谢@destoryer提供的res.json提示！ :)