I have the following Node.js code:
var express = require('express');
var app = express.createServer(express.logger());
app.use(express.bodyParser());
app.post('/', function(request, response) {
response.write(request.body.user);
response.end();
});
Now if I POST something like:
curl -d user=Someone -H Accept:application/json --url http://localhost:5000
I get Someone as expected. Now, what if I want to get the full request body? I tried doing response.write(request.body) but Node.js throws an exception saying "first argument must be a string or Buffer" then goes to an "infinite loop" with an exception that says "Can't set headers after they are sent."; this also true even if I did var reqBody = request.body; and then writing response.write(reqBody).
What's the issue here?
Also, can I just get the raw request without using express.bodyParser()?
Starting from express v4.16 there is no need to require any additional modules, just use the built-in JSON middleware:
app.use(express.json())
Like this:
const express = require('express')
app.use(express.json()) // <==== parse request body as JSON
app.listen(8080)
app.post('/test', (req, res) => {
res.json({requestBody: req.body}) // <==== req.body will be a parsed JSON object
})
Note - body-parser, on which this depends, is already included with express.
Also don't forget to send the header Content-Type: application/json
Express 4.0 and above:
$ npm install --save body-parser
And then in your node app:
const bodyParser = require('body-parser');
app.use(bodyParser);
Express 3.0 and below:
Try passing this in your cURL call:
--header "Content-Type: application/json"
and making sure your data is in JSON format:
{"user":"someone"}
Also, you can use console.dir in your node.js code to see the data inside the object as in the following example:
var express = require('express');
var app = express.createServer();
app.use(express.bodyParser());
app.post('/', function(req, res){
console.dir(req.body);
res.send("test");
});
app.listen(3000);
This other question might also help: How to receive JSON in express node.js POST request?
If you don't want to use the bodyParser check out this other question: https://stackoverflow.com/a/9920700/446681
As of Express 4, the following code appears to do the trick.
Note that you'll need to install body-parser using npm.
var express = require('express');
var bodyParser = require('body-parser');
var app = express();
app.use(bodyParser.urlencoded({ extended: false }));
app.listen(8888);
app.post('/update', function(req, res) {
console.log(req.body); // the posted data
});
For 2019, you don't need to install body-parser.
You can use:
var express = require('express');
var app = express();
app.use(express.json())
app.use(express.urlencoded({extended: true}))
app.listen(8888);
app.post('/update', function(req, res) {
console.log(req.body); // the posted data
});
You should not use body-parser it is deprecated. Try this instead
const express = require('express')
const app = express()
app.use(express.json()) //Notice express.json middleware
The app.use() function is used to mount the specified middleware function(s) at the path which is being specified. It is mostly used to set up middleware for your application.
Now to access the body just do the following
app.post('/', (req, res) => {
console.log(req.body)
})
var express = require('express');
var bodyParser = require('body-parser');
var app = express();
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json())
var port = 9000;
app.post('/post/data', function(req, res) {
console.log('receiving data...');
console.log('body is ',req.body);
res.send(req.body);
});
// start the server
app.listen(port);
console.log('Server started! At http://localhost:' + port);
This will help you. I assume you are sending body in json.
This can be achieved without body-parser dependency as well, listen to request:data and request:end and return the response on end of request, refer below code sample. ref:https://nodejs.org/en/docs/guides/anatomy-of-an-http-transaction/#request-body
var express = require('express');
var app = express.createServer(express.logger());
app.post('/', function(request, response) {
// push the data to body
var body = [];
request.on('data', (chunk) => {
body.push(chunk);
}).on('end', () => {
// on end of data, perform necessary action
body = Buffer.concat(body).toString();
response.write(request.body.user);
response.end();
});
});
In my case, I was missing to set the header:
"Content-Type: application/json"
Try this:
response.write(JSON.stringify(request.body));
That will take the object which bodyParser has created for you and turn it back into a string and write it to the response. If you want the exact request body (with the same whitespace, etc), you will need data and end listeners attached to the request before and build up the string chunk by chunk as you can see in the json parsing source code from connect.
The accepted answer only works for a body that is compatible with the JSON format. In general, the body can be accessed using
app.use(
Express.raw({
inflate: true,
limit: '50mb',
type: () => true, // this matches all content types
})
);
like posted here. The req.body has a Buffer type and can be converted into the desired format.
For example into a string via:
let body = req.body.toString()
Or into JSON via:
let body = req.body.toJSON();
If you're lazy enough to read chunks of post data.
you could simply paste below lines
to read json.
Below is for TypeScript similar can be done for JS as well.
app.ts
import bodyParser from "body-parser";
// support application/json type post data
this.app.use(bodyParser.json());
// support application/x-www-form-urlencoded post data
this.app.use(bodyParser.urlencoded({ extended: false }));
In one of your any controller which receives POST call use as shown below
userController.ts
public async POSTUser(_req: Request, _res: Response) {
try {
const onRecord = <UserModel>_req.body;
/* Your business logic */
_res.status(201).send("User Created");
}
else{
_res.status(500).send("Server error");
}
};
_req.body should be parsing you json data into your TS Model.
I'm absolutely new to JS and ES, but what seems to work for me is just this:
JSON.stringify(req.body)
Let me know if there's anything wrong with it!
Install Body Parser by below command
$ npm install --save body-parser
Configure Body Parser
const bodyParser = require('body-parser');
app.use(bodyParser);
app.use(bodyParser.json()); //Make sure u have added this line
app.use(bodyParser.urlencoded({ extended: false }));
What you claim to have "tried doing" is exactly what you wrote in the code that works "as expected" when you invoke it with curl.
The error you're getting doesn't appear to be related to any of the code you've shown us.
If you want to get the raw request, set handlers on request for the data and end events (and, of course, remove any invocations of express.bodyParser()). Note that the data events will occur in chunks, and that unless you set an encoding for the data event those chunks will be buffers, not strings.
You use the following code to log post data:
router.post("/users",function(req,res){
res.send(JSON.stringify(req.body, null, 4));
});
I can't seem to figure out why when I'm doing an axios.post method providing a body of data, it gets captured as undefined on my server.
I have the following files with snippets of code:
app.js:
auth(user, pass){
return axios.post('http://localhost:3000/auth', {
username: user,
password: pass
})
}
server.js:
app.post('/auth', (req, res) => {
console.log(req.body) //undefined
res.end("Success")
})
I'm how can I properly handle the POST data using axios? Am I missing something?
The success returns fine, but the username / password cannot seem to be found anywhere in the req
I don't have enough reputation to comment on Jim's last post but I had the same problem and that solved it!
To clarify: In my server.js file I was requiring my routes before these:
these first:
app.use(express.urlencoded({ extended: true }));
app.use(express.json());
then this:
app.use(routes);
Add following parser to handle the requested data
var bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json())
Turns out I had all my middleware installed out of order; I was attempting to handle the POST in my server.js file prior to using any middleware.
I'm probably going to ask a huge noob question, one of the worst I've ever had asked here, but I'm lost as hell with Node/Express. I've only used Apache servers (typical WAMP/XAMP for testing purposes), so I have absolutely no idea on what I have to do to serve my web app.
My folder tree is the following:
www
nodeserver.js
(more things)
Liteconomy (my web app)
js
css
plugins
templates
index.html
sublime_project
Pretty typical, huh? Well, I've been searching how to serve this app with a simple access like localhost:8080/Liteconomy, or localhost:8080/Liteconomy.html. After that, my angular routing would do the rest, but I just can't serve the app.
I've got this written in nodeserver.js:
var express = require('express');
var app = express();
app.get('/', function (req, res) {
res.send('Hello World!');
});
app.listen(8080, function () {
console.log('Example app listening on port 8080!');
});
app.get('/Liteconomy', function (req, res) {
res.send('Liteconomy/index.html');
});
When I execute it and access to localhost:8080, I get the "Hello world", but when I go to localhost:8080/Liteconomy, I get the following plain text: "Liteconomy/index.html". If I try to access to the index resource directly, I get a "Cannot GET /Liteconomy/index.html" error.
I also tried using the static thingy, but didn't work either.
What am I doing wrong here? I guess I'm just missing something very important.
Do the following, it will resolve your issue.
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var app = express();
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
// uncomment following if you want to access your app from /liteconomy
//app.use('/liteconomy', express.static(__dirname + '/Liteconomy', {index: "index.html"}));
//This will enable you to access it form '/'
app.use('/', express.static(__dirname + '/Liteconomy', {index: "index.html"}));
// Rest of the stuff
Then if you will visit your URL that you set and port, you'll be able to access.
Using express.static is recommended way of serving static content.
Hope it helps!
You get a plain text answer because you actually ask to do it with the :
app.get('/Liteconomy', function (req, res) {
res.send('Liteconomy/index.html');
});
If you want to send a simple html file like your index.html file, you should use the "sendfile " function :
app.get('/Liteconomy', function (req, res) {
res.sendfile(__dirname + '/Liteconomy/index.html');
});
"__dirname" represents your root directory path and then you simply put your file path.
Hope that helps !
PS : by default express come with jade and ejs template support instead of just using html. I would advise you to take a look at one of them, it can be a great help to construct your application web pages.
Here is my simple form:
<form id="loginformA" action="userlogin" method="post">
<div>
<label for="email">Email: </label>
<input type="text" id="email" name="email"></input>
</div>
<input type="submit" value="Submit"></input>
</form>
Here is my Express.js/Node.js code:
app.post('/userlogin', function(sReq, sRes){
var email = sReq.query.email.;
}
I tried sReq.query.email or sReq.query['email'] or sReq.params['email'], etc. None of them work. They all return undefined.
When I change to a Get call, it works, so .. any idea?
Things have changed once again starting Express 4.16.0, you can now use express.json() and express.urlencoded() just like in Express 3.0.
This was different starting Express 4.0 to 4.15:
$ npm install --save body-parser
and then:
var bodyParser = require('body-parser')
app.use( bodyParser.json() ); // to support JSON-encoded bodies
app.use(bodyParser.urlencoded({ // to support URL-encoded bodies
extended: true
}));
The rest is like in Express 3.0:
Firstly you need to add some middleware to parse the post data of the body.
Add one or both of the following lines of code:
app.use(express.json()); // to support JSON-encoded bodies
app.use(express.urlencoded()); // to support URL-encoded bodies
Then, in your handler, use the req.body object:
// assuming POST: name=foo&color=red <-- URL encoding
//
// or POST: {"name":"foo","color":"red"} <-- JSON encoding
app.post('/test-page', function(req, res) {
var name = req.body.name,
color = req.body.color;
// ...
});
Note that the use of express.bodyParser() is not recommended.
app.use(express.bodyParser());
...is equivalent to:
app.use(express.json());
app.use(express.urlencoded());
app.use(express.multipart());
Security concerns exist with express.multipart(), and so it is better to explicitly add support for the specific encoding type(s) you require. If you do need multipart encoding (to support uploading files for example) then you should read this.
Security concern using express.bodyParser()
While all the other answers currently recommend using the express.bodyParser() middleware, this is actually a wrapper around the express.json(), express.urlencoded(), and express.multipart() middlewares (http://expressjs.com/api.html#bodyParser). The parsing of form request bodies is done by the express.urlencoded() middleware and is all that you need to expose your form data on req.body object.
Due to a security concern with how express.multipart()/connect.multipart() creates temporary files for all uploaded files (and are not garbage collected), it is now recommended not to use the express.bodyParser() wrapper but instead use only the middlewares you need.
Note: connect.bodyParser() will soon be updated to only include urlencoded and json when Connect 3.0 is released (which Express extends).
So in short, instead of ...
app.use(express.bodyParser());
...you should use
app.use(express.urlencoded());
app.use(express.json()); // if needed
and if/when you need to handle multipart forms (file uploads), use a third party library or middleware such as multiparty, busboy, dicer, etc.
Note: this answer is for Express 2. See here for Express 3.
If you're using connect/express, you should use the bodyParser middleware: It's described in the Expressjs guide.
// example using express.js:
var express = require('express')
, app = express.createServer();
app.use(express.bodyParser());
app.post('/', function(req, res){
var email = req.param('email', null); // second parameter is default
});
Here's the original connect-only version:
// example using just connect
var connect = require('connect');
var url = require('url');
var qs = require('qs');
var server = connect(
connect.bodyParser(),
connect.router(function(app) {
app.post('/userlogin', function(req, res) {
// the bodyParser puts the parsed request in req.body.
var parsedUrl = qs.parse(url.parse(req.url).query);
var email = parsedUrl.email || req.body.email;;
});
})
);
Both the querystring and body are parsed using Rails-style parameter handling (qs) rather than the low-level querystring library. In order to parse repeated parameters with qs, the parameter needs to have brackets: name[]=val1&name[]=val2. It also supports nested maps. In addition to parsing HTML form submissions, the bodyParser can parse JSON requests automatically.
Edit: I read up on express.js and modified my answer to be more natural to users of Express.
This will do it if you want to build the posted query without middleware:
app.post("/register/",function(req,res){
var bodyStr = '';
req.on("data",function(chunk){
bodyStr += chunk.toString();
});
req.on("end",function(){
res.send(bodyStr);
});
});
That will send this to the browser
email=emailval&password1=pass1val&password2=pass2val
It's probably better to use middleware though so you don't have to write this over and over in each route.
Note for Express 4 users:
If you try and put app.use(express.bodyParser()); into your app, you'll get the following error when you try to start your Express server:
Error: Most middleware (like bodyParser) is no longer bundled with Express and must be installed separately. Please see https://github.com/senchalabs/connect#middleware.
You'll have to install the package body-parser separately from npm, then use something like the following (example taken from the GitHub page):
var express = require('express');
var bodyParser = require('body-parser');
var app = express();
app.use(bodyParser());
app.use(function (req, res, next) {
console.log(req.body) // populated!
next();
})
Given some form:
<form action='/somepath' method='post'>
<input type='text' name='name'></input>
</form>
Using express
app.post('/somepath', function(req, res) {
console.log(JSON.stringify(req.body));
console.log('req.body.name', req.body['name']);
});
Output:
{"name":"x","description":"x"}
req.param.name x
Backend:
import express from 'express';
import bodyParser from 'body-parser';
const app = express();
app.use(bodyParser.json()); // add a middleware (so that express can parse request.body's json)
app.post('/api/courses', (request, response) => {
response.json(request.body);
});
Frontend:
fetch("/api/courses", {
method: 'POST',
body: JSON.stringify({ hi: 'hello' }), // convert Js object to a string
headers: new Headers({ "Content-Type": "application/json" }) // add headers
});
app.use(express.bodyParser());
Then for app.post request you can get post values via req.body.{post request variable}.
Update for Express 4.4.1
Middleware of the following is removed from Express.
bodyParser
json
urlencoded
multipart
When you use the middleware directly like you did in express 3.0. You will get the following error:
Error: Most middleware (like urlencoded) is no longer bundled with Express and
must be installed separately.
In order to utilize those middleware, now you need to do npm for each middleware separately.
Since bodyParser is marked as deprecated, so I recommend the following way using json, urlencode and multipart parser like formidable, connect-multiparty. (Multipart middleware is deprecated as well).
Also remember, just defining urlencode + json, the form data will not be parsed and req.body will be undefined. You need to define a middleware handle the multipart request.
var urlencode = require('urlencode');
var json = require('json-middleware');
var multipart = require('connect-multiparty');
var multipartMiddleware = multipart();
app.use(json);
app.use(urlencode);
app.use('/url/that/accepts/form-data', multipartMiddleware);
Update
As of Express version 4.16+, their own body-parser implementation is now included in the default Express package so there is no need for you to download another dependency.
You may have added a line to your code that looks like the following:
app.use(bodyparser.json()); //utilizes the body-parser package
If you are using Express 4.16+ you can now replace that line with:
app.use(express.json()); //Used to parse JSON bodies
This should not introduce any breaking changes into your applications since the code in express.json() is based on bodyparser.json().
If you also have the following code in your environment:
app.use(bodyParser.urlencoded({extended: true}));
You can replace that with:
app.use(express.urlencoded()); //Parse URL-encoded bodies
A final note of caution: There are still some very specific cases where body-parser might still be necessary but for the most part Express’ implementation of body-parser is all you will need for the majority of use cases.
(See the docs at expressjs/bodyparser for more details).
I was searching for this exact problem. I was following all the advice above but req.body was still returning an empty object {}. In my case, it was something just as simple as the html being incorrect.
In your form's html, make sure you use the 'name' attribute in your input tags, not just 'id'. Otherwise, nothing is parsed.
<input id='foo' type='text' value='1'/> // req = {}
<input id='foo' type='text' name='foo' value='1' /> // req = {foo:1}
My idiot mistake is your benefit.
For Express 4.1 and above
As most of the answers are using to Express, bodyParser, connect; where multipart is deprecated. There is a secure way to send post multipart objects easily.
Multer can be used as replacement for connect.multipart().
To install the package
$ npm install multer
Load it in your app:
var multer = require('multer');
And then, add it in the middleware stack along with the other form parsing middleware.
app.use(express.json());
app.use(express.urlencoded());
app.use(multer({ dest: './uploads/' }));
connect.json() handles application/json
connect.urlencoded() handles application/x-www-form-urlencoded
multer() handles multipart/form-data
You shoudn't use app.use(express.bodyParser()). BodyParser is a union of json + urlencoded + mulitpart. You shoudn't use this because multipart will be removed in connect 3.0.
To resolve that, you can do this:
app.use(express.json());
app.use(express.urlencoded());
It´s very important know that app.use(app.router) should be used after the json and urlencoded, otherwise it does not work!
Express v4.17.0
app.use(express.urlencoded( {extended: true} ))
app.post('/userlogin', (req, res) => {
console.log(req.body) // object
var email = req.body.email;
}
express.urlencoded
Demo Form
Another Answer Related
Written at Express version 4.16
Inside the router function you can use req.body property to access the post variable. For example if this was the POST route of your form, it would send back what you input:
function(req,res){
res.send(req.body);
//req.body.email would correspond with the HTML <input name="email"/>
}
P.S. for those who are familiar with PHP: In order to access PHP's $_GET variable we use req.query and to access PHP's $_POST variable we use req.body in Node.js.
Request streaming worked for me
req.on('end', function() {
var paramstring = postdata.split("&");
});
var postdata = "";
req.on('data', function(postdataChunk){
postdata += postdataChunk;
});
I could find all parameters by using following code for both POST and GET requests.
var express = require('express');
var app = express();
const util = require('util');
app.post('/', function (req, res) {
console.log("Got a POST request for the homepage");
res.send(util.inspect(req.query,false,null));
})
from official doc version 4
const express = require('express')
const app = express()
app.use(express.json());
app.use(express.urlencoded({ extended: true }))
app.post('/push/send', (request, response) => {
console.log(request.body)
})
var express = require("express");
var bodyParser = require("body-parser");
var app = express();
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
app.get('/',function(req,res){
res.sendfile("index.html");
});
app.post('/login',function(req,res){
var user_name=req.body.user;
var password=req.body.password;
console.log("User name = "+user_name+", password is "+password);
res.end("yes");
});
app.listen(3000,function(){
console.log("Started on PORT 3000");
})
Post Parameters can be retrieved as follows:
app.post('/api/v1/test',Testfunction);
http.createServer(app).listen(port, function(){
console.log("Express server listening on port " + port)
});
function Testfunction(request,response,next) {
console.log(request.param("val1"));
response.send('HI');
}
Use express-fileupload package:
var app = require('express')();
var http = require('http').Server(app);
const fileUpload = require('express-fileupload')
app.use(fileUpload());
app.post('/', function(req, res) {
var email = req.body.email;
res.send('<h1>Email :</h1> '+email);
});
http.listen(3000, function(){
console.log('Running Port:3000');
});
You are using req.query.post with wrong method req.query.post works with method=get, method=post works with body-parser.
Just try this by changing post to get :
<form id="loginformA" action="userlogin" method="get">
<div>
<label for="email">Email: </label>
<input type="text" id="email" name="email"></input>
</div>
<input type="submit" value="Submit"></input>
</form>
And in express code use 'app.get'
Other answers talk about the middleware to use on the server side. My answer attempt to provide developers with a simple playbook to debug the problem themselves.
In this question, the situation is:
You have a form on the client side
The data is sent by clicking on Submit button and you don't use JavaScript to send requests (so no fetch, axios, xhr,... but we can extend the solution for these cases later)
You use Express for the server side
You cannot access data in your Express code. req.body is undefined
There are some actions that you can do to find the solution by yourself:
Open the Network tab and search for your request.
Check the request header Content-Type. In this situation (form submit), the header is likely application/x-www-form-urlencoded or multipart/form-data if you send a file (with enctype="multipart/form-data" in the form tag)
Now check your Express code if you use the appropriate middleware to parse incoming requests.
If your Content-Type is application/x-www-form-urlencoded then you should have app.use(express.urlencoded({extended: true})) in your code.
If your Content-Type is multipart/form-data: because Express doesn't have a built-in middleware to parse this kind of request, you should another library for that. multer is a good one.
If you have done all the steps above, now you can access data in req.body :). If you have problems with the syntax, you should check the Express document page. The syntax could be changed because this question is posted a long time ago.
Now, we can extend this simple playbook for other cases that involve JavaScript code. The key is to check the request Content-Type. If you see application/json then you should use app.use(express.json()) in your code.
In summary, find your request Content-Type, then use the appropriate middleware to parse it.
when you are using POST method in HTML forms, you need to catch the data from req.body in the server side i.e. Node.js.
and also add
var bodyParser = require('body-parser')
app.use( bodyParser.json() );
app.use(bodyParser.urlencoded({extended: false}));
OR
use method='GET' in HTML and and catch the data by req.query in the server side i.e. Node.js