NodeJs how to parse post body sent from Postman

Question

I'm having this simple NodeJs code to handle post request sent from any other origin like Postman

const http = require("http");
const { parse } = require("querystring");
const server = http.createServer(function (request, response) {
console.dir(request.param);

if (request.method === "POST") {
  let body = "";
  request.on("data", (chunk) => {
    body += chunk.toString(); // convert Buffer to string
  });
  request.on("end", () => {
    const result = parse(body);
    console.log(result);
    response.end("ok");
  });
 }
});

const port = 8080;
const host = "127.0.0.1";
server.listen(port, host);

When I send post request from Postman with form data like user:foo I get it like this in the terminal

[Object: null prototype] {
'----------------------------908153651530187984286555\r\nContent-Disposition: form-data; name': '"user"\r\n\r\nfoo\r\n----------------------------908153651530187984286555--\r\n'

And when I run

console.log(result.user)

I get undefined

I changed the parsing body const result = parse(body); into this

const result = JSON.parse(JSON.stringify(body))

And I got

----------------------------939697314758807513697606  
Content-Disposition: form-data; name="user"

foo
----------------------------939697314758807513697606--

but still can't get result.user

How can I handle such data by converting it into an object and get the user like this result.user

Answer 1

If the data in your body is a JSON object, you can just remove the toString in chunks and replace the parse with JSON.parse, like so:

  let body = "";
  request.on("data", (chunk) => {
    body += chunk; // convert Buffer to string
  });
  request.on("end", () => {
    const result = JSON.parse(body);
    console.log(result);
    response.end("ok");
  });

This will work OK if you sent the data from postman choosing "raw" and "JSON", sending an object as the following in the body:

{
    "user": "john"
}

Your current approach, using querystring's parse method, should work well if the data was sent as "x-www-form-urlencoded".

In short, the solution would be to modify the Content-Type header of the request you are sending to your server.