javascript - 使用node js发布请求

Question

我正在尝试使用 node.js 发出发布请求，当我尝试运行它时，我得到的数据显示在控制台中，但没有显示 HTML 的正文。在控制台中我收到错误

app.js:4 POST http://localhost:8000/addAnimal net::ERR_EMPTY_RESPONSE
postData @ app.js:4
(anonymous) @ app.js:25
app.js:21 Uncaught (in promise) TypeError: Failed to fetch

看起来该功能正在运行，但实际的发布请求部分却不起作用。我一生都无法弄清楚我做错了什么。

这是我的代码:

服务器.js:

projectData = {};

/* Express to run server and routes */
const express = require('express');

/* Start up an instance of app */
const app = express();

/* Dependencies */
const bodyParser = require('body-parser')
/* Middleware*/
app.use(express.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
const cors = require('cors');
app.use(cors());

/* Initialize the main project folder*/
app.use(express.static('project1'));

const port = 8000;
/* Spin up the server*/
const server = app.listen(port, listening);
 function listening(){
    // console.log(server);
    console.log(`running on localhost: ${port}`);
  };

// GET route
app.get('/all', sendData);

function sendData (request, response) {
  response.send(projectData);
};

// POST route
app.post('/add', callBack);

function callBack(req,res){
  res.send('POST received');
}

// POST an animal
const data = [];


  // TODO-Call Function



app.route('/addAnimal')
  .get(function (req, res) {
    res.sendFile('index.html', {root: 'project1'})
  })
  .post(function (req, res) {
    data.push(req.body)
  })

app.js

/* Function to POST data */
const postData = async ( url = '', data = {})=>{
    console.log(data);
      const response = await fetch(url, {
      method: 'POST', // *GET, POST, PUT, DELETE, etc.
      credentials: 'same-origin', // include, *same-origin, omit
      headers: {
          'Content-Type': 'application/json',
      },
      body: JSON.stringify(data), // body data type must match "Content-Type" header        
    });

      try {
        const newData = await response.json()
        // console.log(newData);
        return newData.json()
      }catch(error) {
      console.log("error", error)
      // appropriately handle the error
      };
  };

  // TODO-Call Function

  postData('/addAnimal', {animal:'lion'});

任何帮助将非常感激。

谢谢，迈克

Answer 1

💡 The only one reason why you got message like it, it's because you never send response to the client.

👨‍🏫 因此，您应该向客户端发送响应。例如，您可以查看下面的代码:👇

app.route('/addAnimal')
  .get(function (req, res) {
    res.sendFile('index.html', {root: 'project1'})
  })
  .post(function (req, res) {
    data.push(req.body);
    // send data to client
    // you can change req.body with the object what you want to sent do the client
    res.status(200).send(req.body);
  })

📤更新:其他信息

Make sure you call the endpoint: http://localhost:8000/addAnimal.

前端:确保您的代码类似于下面的代码

const postData = async ( url = '', data = {})=>{
    const response = await fetch(url, {
      method: 'POST', // *GET, POST, PUT, DELETE, etc.
      credentials: 'same-origin', // include, *same-origin, omit
      headers: {
          'Content-Type': 'application/json',
      },
      body: JSON.stringify(data), // body data type must match "Content-Type" header        
    });
    try {
      console.log(await response.json());
      return await response.json()
    }catch(error) {
      console.log("error", error);
    };
};

希望对你有帮助🙏。