Node.js + React: How to POST - node.js

Follow on from this question: Axios can GET but not POST to the same URL
I've been trying to figure this out for too long now.
I want to POST from my React app to a .JSON file. Can anyone tell me what I'm doing wrong?
My AJAX POST function using axios always returns a 404. I'm listening for it on the node server but app.post never fires.
Thanks.
POST request from my React app:
postJson = (postJsonData) => {
axios.post('./postJson/', {
postJsonData
})
.then(function (response) {
console.log("success!");
console.log(response);
})
.catch(function (error) {
console.log(error);
});
}
app.js (node server):
/*========== Default Setup for node server copied from node website ==========*/
const http = require('http');
const hostname = '127.0.0.1';
const port = 3001;
const server = http.createServer((req, res) => {
res.statusCode = 200;
res.setHeader('Content-Type', 'text/plain');
res.end('Hello World\n');
});
server.listen(port, hostname, () => {
console.log(`Server running at http://${hostname}:${port}/`);
});
/*========== Listen for POST (Trying to get the data from my REACT app
- will then assign it to "obj" below) ==========*/
var express = require("express");
var myParser = require("body-parser");
var app = express();
app.post("./postJson/", function(request, response) {
console.log("MURRRR");
console.log(request.body); //This prints the JSON document received (if it is a JSON document)
/*=== JSON Stuff ===*/
var jsonfile = require('jsonfile')
var file = './scene-setup.json'
var obj = {name: 'JP'}
jsonfile.writeFile(file, obj, function (err) {
console.error(err)
})
});
//Start the server and make it listen for connections on port 3000
app.listen(3000, function(){
console.log("server is listening to 3000");
});

Two things I noticed:
Your post endpoint doesn't need a leading "." I would make it just "/postJson"
Make sure you are posting to "http://localhost:3000/postJson"
Make sure you have the network tab open to see the actual URL you are requesting to.
Cheers

Turns out both react and my node server were running on localhost:3000 simultaneously which is apparently not okay.
Running my node server on localhost:3001 from a new command line window allowed me to do both at the same time.
Not sure how this would work when making a production build though.

Related

Debian server, Node js Port 3000 listening But cant access via browser

On my debian server, I installed node and then started node server on port 3000. The server is running, but it isn't visible from the browser
Now when I try to get it running via my domain or via my ip(for example xx.xxx.xx.xx:3000) or my domain (my-domain.com:3000) in both cases it doesn't work. I think I don't quite get the concept and I tried to search for a billion different things, but I can't find the solution to my problem. Could someone tell me, if I need to setup something else, too?
My server js code is
const express = require('express');
const app = express();
const http = require('http');
const server = http.createServer(app);
const { Server } = require("socket.io");
const io = new Server(server);
server.listen(3000, () => {
console.log('listening on *:3000');
});
io.on('connection', function (socket) {
socket.on( 'new_message', function( data ) {
io.sockets.emit( 'new_message', {
message: data.message,
date: data.date,
msgcount: data.msgcount
});
});
});
Error i got
You need to listen for GET requests in order to respond to them.
Try adding something like:
app.get('/', function (req, res) {
res.send('GET request test.')
})
In your case make sure you add the route before passing the app to the http.createServer() method, or otherwise just use something like app.listen(3000).
More info in the docs: https://expressjs.com/en/guide/routing.html
why are you using express and http both packages.
you can run server by either of them.
and then add a get route for it.
import { createServer } from "http";
import { Server } from "socket.io";
const httpServer = createServer();
const io = new Server(httpServer, {
// ...
});
io.on("connection", (socket) => {
// ...
});
httpServer.listen(3000);
I hope this will work!

How to recieve a file using request.get()?

I am writing a server that is meant to serve and receive files. It is written in node.js, using express.js. I also have a client, also written in node, which is meant to send a request to the server and receive the files on the server.
Server-side
const express = require("express");
const app = express();
const file = "./samplefiles/Helloworld.txt";
app.get("/", (res)=>{
res.download(file);
});
module.exports = app; //this exports to server.js
const http = require("http");
const app = require("./app.js);
const port = 8080;
const server = http.createServer(app);
server.listen(port, () => {
console.clear();
console.log("server running");
})
Client-side
const request = require("request");
request.get("http://localhost:8080/", (req, body) => {
console.log(body);
console.log(res);
});
If I try to access it by my browser I am asked what I want to do with the file, it works. However, Is I run my client-side code it prints the body and the res(being null). I expected the file name and it's content to be in the body but only the content of the file was in the body.
I want to receive the whole file, is possible, or at least get the name of it so that I can "make" a copy of it on the client-side.
Change code your server side to:
const port = 8080;
const express = require("express");
const app = express();
const path = require('path');
app.get("/", function(req, res){
res.sendFile(path.join(__dirname, 'app.js'));
});
app.listen(port, () => {
console.clear();
console.log("server running");
});
Change code your client-side to:
var request = require('request');
request('http://localhost:8080/', function (error, response, body) {
console.log('error:', error); // Print the error if one occurred
console.log('statusCode:', response && response.statusCode); // Print the response status code if a response was received
console.log('body:', body); // Print data of your file
});
You need to install request npm i request for client side
You can serve up any files you want with express static method:
app.use(express.static('public'))
in this case just put all the files you want to serve in folder called public and then you can access it by localhost:8080/Helloworld.txt.
I ended up working around it.
I sent the file name as a header and was thus able to create a replica of the file I wanted to download using the body info and the filenameheader.

XMLHTTPRequest not working on server on localhost

I'm developing a node.js RESTful server for home use on a RPI with Raspbian, and for testing, I've created a test HTML page that makes various XMLHttpRequests to it.
When developing I'm using a test nodemon server on my dev machine (a desktop machine, not the RPI), running on localhost:4000, and the test HTML page points to it.
Whenever I'm ready to commit the changes, I push them to the server (the RPI), even the test page. It should connect to the server on localhost.
Something bizzare happens whenever I'm testing the page on the server: localhost is not recognized in the XMLHttpRequest.open method, but if I put the address of the server machine in the network (not 127.0.0.1, but 192.168.1.X for example), it works.
The Command netstat -vltn shows that the node server is listening on port 4000, I've enabled CORS, I've already tried to write 127.0.0.1 instead of localhost, and I've even modified the app.listen function to listen to 0.0.0.0, like this:
app.listen(port, '0.0.0.0', function () {
console.log('RESTful API server started on: ' + port);
});
but still, every request from the test page hosted on the server, to localhost:4000 doesn't work.
My problem here is that, if I need to push the test page on the server, I need to manually change the IP address for the XMLHttpRequest each time, instead of just keeping localhost. Is there a way to enable the use of localhost?
EDIT: I'm adding some client code to flesh out the problem.
testpage.html (the one that should work both on the dev machine and the RPI)
<html>
<head>
<script type="text/javascript">
function sendData() {
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function () {
if (this.readyState == 4 && this.status == 200) {
// Typical action to be performed when the document is ready:
document.getElementById("demo").innerHTML = xhttp.responseText;
}
};
xhttp.onerror = function(e) {
console.log('error', e);
};
xhttp.open("POST", "http://127.0.0.1:4000/auth/loginTest", true);
xhttp.setRequestHeader("Content-Type", "application/json");
//I've omitted the part where I'm prepping a json with username/password data
xhttp.send(jsonString);
}
</script>
</head> <!--I'm skipping the rest of the code as there's only a div that
catches the json info sent by the server -->
server.js (the one that gets started on the RPI with node server.js)
var express = require('express');
var cors = require('cors');
var bodyParser = require('body-parser');
var port = process.env.PORT || 4000;
var auth = require(/*path to Auth middleware*/);
var app = express();
app.use(bodyParser.json({ type: 'application/json' }));
app.options('*', cors());
app.use(cors());
app.use('/auth', auth);
process
.on('unhandledRejection', (reason, p) => {
console.error(reason, 'Unhandled Rejection at Promise', p);
})
.on('uncaughtException', err => {
console.error(err, 'Uncaught Exception thrown');
process.exit(1);
});
app.listen(port, function () {
console.log('RESTful API server started on: ' + port);
});
Try changing this code:
app.listen(port, '0.0.0.0', function () {
console.log('RESTful API server started on: ' + port);
});
to this:
app.listen(port, function () {
console.log('RESTful API server started on: ' + port);
});
This will allow your app to listen on both IPv4 and IPv6. It is possible that localhost is resolving to the IPv6 address and your code is only listening on the IPv4 address. I know that a MAC uses IPv6 for localhost.
The other thing to try is stop using the word localhost on the client and use 127.0.0.1 and see if that makes any difference.
UPDATE:
Below is my server code that I generated from yours and it seems to work:
const express = require('express');
const cors = require('cors');
const bodyParser = require('body-parser');
const port = process.env.PORT || 4000;
function sendPage(req, res, next) {
console.log('sending page');
res.send(`<html>
<head>
<script>
function sendData() {
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function () {
if (this.readyState == 4 && this.status == 200) {
// Typical action to be performed when the document is ready:
document.getElementById("demo").innerHTML = xhttp.responseText;
}
};
xhttp.onerror = function(e) {
console.log('error', e);
};
xhttp.open("POST", "http://127.0.0.1:4000/auth/loginTest", true);
xhttp.setRequestHeader("Content-Type", "application/json");
//I've omitted the part where I'm prepping a json with username/password data
xhttp.send('{"user":"dog","pw":"woof"}');
}
</script>
</head>
<body onload="sendData()">
<h1>Test page</h1>
<div id="demo"></div>
<hr/>
</body>
</html>`);
}
function auth() {
console.log('auth called');
var router = express.Router();
router.post('/loginTest', (req, res, next) => {
console.log('auth was called');
console.log(req.body);
res.json({error: false, data:'hi'});
});
return router;
}
const app = express();
app.use(bodyParser.json({ type: 'application/json' }));
app.options('*', cors());
app.use(cors());
app.get('/', sendPage);
app.use('/auth', auth());
process
.on('unhandledRejection', (reason, p) => {
console.error(reason, 'Unhandled Rejection at Promise', p);
})
.on('uncaughtException', err => {
console.error(err, 'Uncaught Exception thrown');
process.exit(1);
});
app.listen(port, function () {
console.log('RESTful API server started on: ' + port);
});
If this doesn't come close to matching your code let me know where I got it wrong.
Sorry for the delay. I forgot to post the solution.
My approach will never work, because when the test page is loaded, it will try to execute a script on http://localhost:4000, which is fine if the page is loaded from the machine where the server is listening, but obviously won't work if it's on another machine (hence the ERR_CONNECTION_REFUSED error).
If I load this page from the server machine it will try to execute the script on my machine, which is an invalid request.
So I've solved it by simply substitute http://localhost:4000 in the request with the actual IP of the machine, e.g http://Write.Real.Address.Here:4000.

Axios can GET but not POST to the same URL

I'm building a react app
In one component I'm writing this GET request which works:
In another component I'm writing this POST request:
Which then returns this 404 error:
And I have no idea how my GET works but my POST returns 404:not found when I'm requesting the same file both times?
UPDATE:
I'm running a node.js server now but it's a bit of a frankenstein's monster as this really isn't an area I have an understanding of. Does anyone know what I'm doing wrong?
// Server setup from node.js website
const http = require('http');
const hostname = '127.0.0.1';
const port = 3000;
const server = http.createServer((req, res) => {
res.statusCode = 200;
res.setHeader('Content-Type', 'text/plain');
res.end('Hello World\n');
});
server.listen(port, hostname, () => {
console.log(`Server running at http://${hostname}:${port}/`);
});
// Trying to listen for data from React app to feed into JSON (broken)
var express = require("express");
var myParser = require("body-parser");
var app = express();
app.use(myParser.urlencoded({extended : true}));
app.post("/scene-setup.json", function(request, response) {
console.log(request.body); //This prints the JSON document received (if it is a JSON document)
});
app.listen(3001);
// Updating JSON file with "obj" (working)
var jsonfile = require('jsonfile')
var file = './scene-setup.json'
var obj = {name: 'JP'}
jsonfile.writeFile(file, obj, function (err) {
console.error(err)
})
Axios is used for making HTTP requests. So, you should have a backend server running that can handle these requests. I am not sure what exactly is the data that you want to save. If you need access to that data, should be saving it on the backend.
If you want to save some data just on the client side, HTML5 filesystem API might be something you want to look at. It can manage some data in the limited sandboxed part of user's filesystem.

Html content is not showed in NodeJS

I'm trying to create an http server. The server is created correctly but does NOT show the html content. It works when I do it without listeners. What am I failing then?
app.js
var server = require("./server.js");
server.server3((req, res, html) => {
res.writeHead(200, {"Content-Type": "text/html"});
html.pipe(res);
res.end();
}, 3000, "./index.html");
server.js
function Server3(applyFunction, port, path) {
var fs = require("fs"),
html = fs.createReadStream(path.toString().trim()), // Create stream from path
http = require("http");
html.on("data", _ => {})
.on("end", () => { // create server when all data is ready
http.createServer(function(req, res){ // createServer method
applyFunction(req, res, html); // execute the function
}).listen(+port); // add the port
});
}
module.exports.server3 = Server3;
If you're just trying to create an HTTP server on node.js, using the express framework (npm install express --save) would simplify your life a great deal. If you place the index.html file in the same directory as app.js, you can create the server with the following 5 lines of code:
// Setup Express
const express = require("express");
const app = express();
// Use main directory to find HTML file
app.use(express.static(__dirname));
// Render index.html
app.get("/", (req, res) => res.render("index"));
// Start Server on port 3000
app.listen(3000, () => console.log('Server started on port 3000'));

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