Question 233062 in Javascript Question posted in
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Javascript – Why is my Node JS POST request sending [object Object]?

I’m writing a program which sends a small piece of JSON data from a page to a server. Whenever I run the code and send the data, trying to read it on the server side just shows it as ‘[object Object]’

Here’s my server side code for reading this specific request

async function serve(request, response){var requestURL = new URL(request.url, https://${request.headers.host})var path = requestURL.pathname;


    req = ""
    request.on("data", (data)=>{
        req += data;
    })
    request.on("end", ()=> {
        console.log(JSON.stringify(req));
    })

}

Then here’s my client side

const response = await fetch("./login", {
    method: "POST",
    headers: {
        "Content-Type": "application/json"
    },
    body: JSON.stringify({name: "John Doe"})
    });
}

There are a few similar issues like this already, but they’re all either for people using Express, which I am not using, or people trying to send larger requests than a tiny JSON object.

I’ve tried sending it in a few different formats, as a string, changing the structure of the object, reading it as a string on the server side, concatenating it while logging to the console, etc.

What can I do to fix this problem?

Tags:

2

Answers


  1. 0

    On this line: req += data; you add the req variable (which is a string) to the data object.

    In JavaScript an when you concatenate an Object with a string, JavaScript will call the toString method on the object, and therefore return [object Object]

    so req += data is the same as req += data.toString() and data.toString() returns [object Object]

    If you want to merge the objects, you can do that with the Object.assign()

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  2. 0

    Use JSON.parse() instead of JSON.stringify on the within the request’s data end event.

     console.log(JSON.parse(req));
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