Express request body return null - javascript

I have a problem with express POST request,
const express = require('express')
const app = express()
app.use(express.json())
app.use(express.urlencoded({extended: true}))
app.post('/movie/add', (req, res) => {
console.log(req.body) // {}
//
})
can someone tell me, why after sending some data like:
{
"msg":"Hello"
}
then my req.body return me {}? He should return me an object of my msg value but instead of I have an empty array :/
thanks for any help!

You need to do two things if you want to use the request body.
1.in request header include Content-type application/json
2.in code Use middleware to parse into json. app.use(express.json());
Note use ​app.use(express.json()) before route declartion.
view example here
Bydefault body is undefined
app.use(express.json()); help you to defined the data
while content-type application/json allow you to pass json.if you did not include content-type application/json request.body will return define empty object { }.

I think you should use body-parser
http://expressjs.com/en/resources/middleware/body-parser.html

Related

Req.body is empty for POST request in Express

I try to use Postman for generating some post transaction of my web but when I check the post method of my code it print the empty {} and add the empty {} to my list. I try to use middleware but the problem is still occurring.
This is my code.
// my code at restaurant.js
const express = require("express");
const router = express.Router();
const restaurants = require("../data")
router.get("/",(req,res) =>{
res.json(restaurants);
}
)
router.get("/:id",(req,res) =>{
const restaurantid = Number.parseInt(req.params.id,10);
const restaurant = restaurants.find((restaurant) => restaurant.id === restaurantid);
res.json(restaurant);
})
router.post("/",(req,res)=>{
console.log(req.body);
new_restaurant = req.body;
restaurants.push(new_restaurant);
res.json(new_restaurant);
}
)
module.exports = router;
//my code at index.js
const express = require("express");
const app = express();
const router = express.Router();
const restaurantsRouter = require("./routes/restaurants.js");
// Middleware
app.use(express.json());
app.use(express.urlencoded({extended:false}));
// Routes
app.use("/apis/restaurants",restaurantsRouter);
app.get("/",(req,res)=>{
res.send("<h1>Hello Express</h1>");
});
app.listen(3000,()=> {
console.log("Listening to port 3000");
})
module.exports = router;
The general reasons for an empty req.body on an incoming POST request are as follows:
You are failing to send the body properly with whatever client is sending the request.
You are failing to set the right content-type with the request that matches the type of the body data you are sending. If you're sending JSON, then you will need to make sure the incoming request has the content-type application/json.
You don't have the right middleware installed or working properly that will match the incoming content-type, read the body from the incoming stream, parse it and put the parsed results in req.body.
The middleware for parsing that content-type is not registered before your route handler in Express.
Some other middleware is "eating" the body before your middleware so the body is empty when it gets to your JSON middleware.
So, you will need to go through your POST request and eliminate each of these possibilities until you find the problem.

How Do I Get Body From Get Request In Express?

My Code Returns Invalid Text When I Try To Do It.
app.post("/charge", (req, res) => {
console.log(req.body)
})
As the doc for req.body says:
req.body contains key-value pairs of data submitted in the request body. By default, it is undefined, and is populated when you use body-parsing middleware such as express.json() or express.urlencoded().
The following example shows how to use body-parsing middleware to populate req.body.
By default, the body of the request is not yet read from the incoming stream and therefore it is not yet parsed into req.body either. To get it read and parsed into req.body, you have to use some appropriate middleware that will do that for you (or you could do it manually yourself, but it's generally easier to use pre-written middleware that does the job for you).
Which middleware to use depends upon the type of the data in the body (urlEncoded data, JSON data or something else).
Here's the example from the doc:
var express = require('express')
var app = express()
app.use(express.json()) // for parsing application/json
app.use(express.urlencoded({ extended: true })) // for parsing application/x-www-form-urlencoded
app.post('/profile', function (req, res, next) {
console.log(req.body)
res.json(req.body)
})

Express.js + body-parser: empty req.body from POST request

I am using Express and body-parser middleware to process incoming requests. On the front end, I have a form that's just a hidden input and a submit button (written in Pug):
form(notes="saveNotesForm" action=`/lessons/${lesson._id}/notes` method="POST" enctype="application/x-www-form-urlencoded")
input(type="hidden" id="hiddenNotes" name="hiddenNotes" alt="Notes Copy" value="test").notesHidden
input(type="submit" name="saveNotes" alt="Save Notes" value="Save")
On the backend, I have the Express app using body-parser:
const bodyParser = require('body-parser');
// ...
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
And the route processing the incoming request:
router.post('/lessons/:lessonID/notes', lessonController.updateNotes);
// ... and in lessonController:
exports.updateNotes = async (req, res) => {
console.log('updateNotes request received');
console.log(req.body);
res.status(200).json({ status: 'success' });
}
When I try to use req.body in updateNotes, the body is an empty object, but should at least have the property hiddenNotes with the value "test". Please comment if you have any questions or think you see the problem!
[UPDATED]
This was a silly mistake, I forgot I had written a separate event handler for when this form gets submitted - it just took me posting on SO before I went through all of my code :) The event handler uses axios and looks like this:
const SaveNotesButton = $('form.saveNotes');
SaveNotesButton.on('submit', ajaxSaveNotes);
function ajaxSaveNotes(e) {
e.preventDefault();
axios
.post(this.action)
.then(res => {
console.log(res.data);
})
.catch(console.error);
}
Unfortunately, when making posts with axios, you need to include the data in an object like this, or else it won't be included in the request:
const SaveNotesButton = $('form.saveNotes');
SaveNotesButton.on('submit', ajaxSaveNotes);
function ajaxSaveNotes(e) {
e.preventDefault();
axios
.post(this.action, { notes: this.children.hiddenNotes.value }) // Data added here
.then(res => {
console.log(res.data);
})
.catch(console.error);
}
Have to tried querying your end point using Postman or something similar?
There could be one possible explanation for why your req.body is undefined. Are you sure your app.use(bodyParser.json()) and app.use(bodyParser.url... are written before your app.use('***', router) lines? If you put the body parser middleware AFTER your router middleware it essentially won't get called because middleware are called in the order they are put in app.use. So you should place your bodyParser before all your router logic. BodyParser middleware then calls all the other middleware (with the req.body populated) that come after it including all your router level middleware.
Hope it helps!
Not sure how you are defining your routes but I would expect a post route to look like the following:
const express = require('express');
const app = express();
app.use(bodyParser.urlencoded({extended: true}));
app.use(bodyParser.json());
app.post('/lessons/:lessonID/notes', (req, res) => {
// now pass the req object to your function
lessonController.updateNotes(req);
});
You need to pass the req object to your function to be able to access req.body...

Node.js unable to read POST JSON data in my webhook

I have a node.js + Express application. It has a webhook that I have provided to a third party service. The service sends a POST request to my webhook with JSON body which looks something like this:
{"split_info" : "null", "customerName" : "Merchant Name",
"additionalCharges" : "null", "paymentMode":"CC",
"hash":"a31ff1b91fd9b8ae9c82f38b02348d21fsdfd86cc828ac9a0acf82050996372cc656de3db0fe3bf9af52b73a182a77787241f3e19ec893391607301b03e70db8",
"status" : "Release Payment", "paymentId" : "551731" ,
"productInfo":"productInfo", "customerEmail":"test#gmail.com",
"customerPhone":"9876543212", "merchantTransactionId":"jnn",
"amount":"100.0", "udf2":"null", "notificationId" :"4", "udf1":"null",
"udf5":"null", "udf4":"null", "udf3":"null","error_Message":"No
Error"}
I am using body-parser module to read POST data. However when I do req.body it gives [object Object], if I do JSON.stringify(req.body), it gives {} i.e. empty. If I try to access the keys in the response like req.body.paymentMode then it gives undefined.
Here is my router code for the webhook: mywebhook.js
var express = require('express');
var router = express.Router();
router.post('/success', function(req, res){
//this is where I need to strip the JSON request
//req.body or JSON.stringify(req.body) or anything that works
//if everything is okay then I send
res.sendStatus(200);
});
module.exports = router;
My app.js looks like this:
var express = require('express');
var exphbs = require('express-handlebars');
var router = express.Router();
var bodyParser = require('body-parser');
var mywebhook = require('./routes/mywebhook');
var app = express();
.
.
.
app.use(bodyParser.urlencoded({'extended':'true'})); // parse application/x-www-form-urlencoded
app.use(bodyParser.json()); // parse application/json
app.use(bodyParser.json({ type: 'application/vnd.api+json' })); // parse application/vnd.api+json as json
app.use('/callwebhook', mywebhook);
.
.
.
so on
Pretty sure I am missing something or doing something wrong, but I am not able to figure it out.
Thanks.
I finally found what was going on.
The way the body-parser works is that it will only try to parse a request in which they understand the Content-Type. This is mainly so you can stack them (app.use multiple parser types without conflict) and also because you typically don't want to parse a request that's going to fail (Content-Type: text/html is unlikely to ever get through a JSON.parse, for example).
I ended up getting sent */*; charset=UTF-8 which is not even a valid Content-Type header value period. The body-parser module refused to accept it, since that is gibberish. This module does allow you to setup a function that lets you put any custom logic you want to perform the filtering.
I had to put the body parser in my router code just for this webhook case.
var bodyParser = require('body-parser');
var customParser = bodyParser.json({type: function(req) {
return req.headers['content-type'] === '*/*; charset=UTF-8';
}});
router.post('/success', customParser, function(req, res){
console.log(JSON.stringify(req.body));
});
#svens thank you for your help.

Express js - request body is empty

I just installed the latest versions of modules. I can not get any GET or POST variables. What i do wrong?
NODE: v0.12.2
var express = require("express");
var bodyParser = require("body-parser");
var app = express();
app.use(bodyParser.urlencoded({ extended: false }))
// parse application/json
app.use(bodyParser.json())
app.use(function (req, res) {
res.setHeader('Content-Type', 'text/plain')
res.write('you posted:\n')
res.end(JSON.stringify(req.body, null, 2))
});
app.listen(3000,function(){
console.log("Started on PORT 3000");
})
http://localhost:3000/?token=devvvvv GET returns:
you posted:
{}
Thanks for answers, but problem with POST does not solved...
POST token=as123ds on http://localhost:3000/ return empty array in req.body
How can i solve this?
You are submitting parameters via the query string and attempting to access them through the request body which in this case is empty.
The token parameter will be available in request.query like so:
app.use(function (req, res) {
res.setHeader('Content-Type', 'text/plain')
res.write('you posted:\n')
res.end(JSON.stringify(req.query.token, null, 2))
});
If you only plan to submit parameters in the query string you should not need to mount the body-parser middleware at all.
You should be using the req.query:
req.query
An object containing a property for each query string parameter in the route. If there is no query string, it is the empty object, {}.
api link
You are parsing JSON from the request, so the POST from client must have 'Content-Type': 'application/json' in HTTP header. If not, you'll have empty request.body at server side.
bodyparser module requires the http request's "Content-type" property equal to "application/json". It won't work for other values.
You have to check the request content type in the client, this link may help
Node (Express) request body empty
This is because bodyParser parses application/json,
application/x-www-form-encoded and multipart/form-data, and it selects
which parser to use based on the Content-Type.

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