New line in json array is getting converted to a comma | nodejs - json

Question

I am relatively new to nodejs and running into an issue while parsing a Json post request.
Here is the JSON format of the post request:
{"parameters":{"issuerId":[96409],"source":["'XYZ'"]}}
And here is my code to read it.
function getSearchData(req, res, next) {
console.log("req is" + req.body);
try {
JSON.parse(reqJSON);
} catch (e) {
console.log(e);
}
}
This parsing works fine and I am able to parse it and do my further logic. However, if I change my format of post request(same request with additional new lines) it fails to parse as it adds additional commas in place of each new line in the request.
{
"parameters": {
"issuerId": [96409],
"source":["'XYZ'"]
}
}
Here's the output from the code with the second request.
req is{,"parameters":{"id":[96409],,"source":["'XYZ'"]}}
[SyntaxError: Unexpected token ,]
If you notice, an extra comma gets added at each new line, which was never in the request to begin with.
What am I doing wrong here?

Answer 1

You should never have to parse the JSON yourself, unless you're concatenating the request body stream yourself.
Hint 1: Do you use any framework like Express? Do you use body parser?
Hint 2: How do you create the JSON?
Hint 3: Do you use correct content-type?
Hint 4: How do you create req.body from the request stream?
You didn't include the entire code so it's impossible to give you a specific solution.
What am I doing wrong here?
Whatever you're doing wrong here, it's not included in the question.
However, if I change my format of post request(same request with additional new lines)
It would be useful if you included more details of how you do it.
I see two potential sources of that problem:
either the commas are introduced during the on the client side
or they are introduced during the request reading on the server side
You didn't show us any of those two parts - you didn't show the serializing code and the code that sends the data, and you didn't include the code that gets the data, possibly joins it from chunks and parses the JSON. But the problem is likely in one of those parts.
Update
Here is an example on how to do what you need using Express. You didn't answer whether you use any framework like Express or not, but I think that you should if you can't achieve that simple task without it, so here is a working example:
const express = require('express');
const bodyParser = require('body-parser');
const app = express();
function getSearchData(req, res, next) {
console.log('req body is', req.body);
console.log('req body JSON is', JSON.stringify(req.body));
res.json({ ok: true });
}
app.use(bodyParser.json());
app.use(getSearchData);
app.listen(3335, () => console.log('Listening on http://localhost:3335/'));
It shows how to correctly get a parsed JSON request body as an object req.body, how to print the data as a standard console.log representation and serialized again as JSON. See how it works and compare it to your own solution. This is all I can do because not having seen your entire solution I cannot tell you more than the hints that I've already given.