为什么请求正文未定义？

Question

我有一个index.js文件：

const express = require('express');
const bodyParser = require('body-parser');
const cors = require('cors');

const db = require('./db');
const movieRouter = require('./routes/movie-router');

const app = express();
const apiPort = 3000;

app.use(bodyParser.urlencoded({ extended: true }));
app.use(cors());
app.use(bodyParser.json());

db.on('error', console.error.bind(console, 'MongoDB connection error:'));

app.get('/', (req, res) => {
    res.send("Hello, World");
});

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

app.listen(apiPort, () => console.log(`Server running on port ${apiPort}`));

这是我的/routes/movie-router.js文件：

const express = require('express')

const MovieCtrl = require('../controllers/movie-ctrl')

const router = express.Router()

router.post('/movie', MovieCtrl.createMovie)
router.put('/movie/:id', MovieCtrl.updateMovie)
router.delete('/movie/:id', MovieCtrl.deleteMovie)
router.get('/movie/:id', MovieCtrl.getMovieById)
router.get('/movies', MovieCtrl.getMovies)

module.exports = router

这是/conterollers/movie-ctrl.js文件：

const Movie = require('../models/movie-model')
const bodyParser = require('body-parser')

createMovie = (req, res) => {
    const body = req.body

    if (!body) {
        return res.status(400).json({
            success: false,
            error: 'You must provide a movie',
        })
    }

    const movie = new Movie(body)

    if (!movie) {
        return res.status(400).json({ success: false, error: err })
    }

    movie
        .save()
        .then(() => {
            return res.status(201).json({
                success: true,
                id: movie._id,
                message: 'Movie created!',
            })
        })
        .catch(error => {
            return res.status(400).json({
                error,
                message: 'Movie not created! ',
            })
        })
}

updateMovie = async (req, res) => {
    const body = req.body

    if (!body) {
        return res.status(400).json({
            success: false,
            error: 'You must provide a body to update',
        })
    }

    Movie.findOne({ _id: req.params.id }, (err, movie) => {
        if (err) {
            return res.status(404).json({
                err,
                message: 'Movie not found!',
            })
        }
        movie.name = body.name
        movie.time = body.time
        movie.rating = body.rating
        movie
            .save()
            .then(() => {
                return res.status(200).json({
                    success: true,
                    id: movie._id,
                    message: 'Movie updated!',
                })
            })
            .catch(error => {
                return res.status(404).json({
                    error,
                    message: 'Movie not updated!',
                })
            })
    })
}

deleteMovie = async (req, res) => {
    await Movie.findOneAndDelete({ _id: req.params.id }, (err, movie) => {
        if (err) {
            return res.status(400).json({ success: false, error: err })
        }

        if (!movie) {
            return res
                .status(404)
                .json({ success: false, error: `Movie not found` })
        }

        return res.status(200).json({ success: true, data: movie })
    }).catch(err => console.log(err))
}

getMovieById = async (req, res) => {
    await Movie.findOne({ _id: req.params.id }, (err, movie) => {
        if (err) {
            return res.status(400).json({ success: false, error: err })
        }

        return res.status(200).json({ success: true, data: movie })
    }).catch(err => console.log(err))
}

getMovies = async (req, res) => {
    await Movie.find({}, (err, movies) => {
        if (err) {
            return res.status(400).json({ success: false, error: err })
        }
        if (!movies.length) {
            return res
                .status(404)
                .json({ success: false, error: `Movie not found` })
        }
        return res.status(200).json({ success: true, data: movies })
    }).catch(err => console.log(err))
}

module.exports = {
    createMovie,
    updateMovie,
    deleteMovie,
    getMovies,
    getMovieById,
}

当我尝试使用POSTMAN手动发布数据时，它返回状态：400（错误请求）：

enter image description here

但是，当我更改body const的值时：

const body = req.body

到我要发布的数据对象，像这样：

const body = {
        "name": "Avengers: Endgame",
        "time": ["14:15", "16:00", "21:30", "23:00"],
        "rating": 8.8
    }

然后，发布请求成功。

Answer 1

在Postman中，您需要将正文的格式从“文本” 更改为“ JSON” ：