JSON Web Tokens Node JS Server ERROR SyntaxError: Unexpected token } in JSON at position 24-CodePudding

Me and others are experiencing this error: SyntaxError: Unexpected token } in JSON at position 24 at JSON.parse (<anonymous>) while following this tutorial on JSON Web Tokens (LINK: https://www.youtube.com/watch?v=mbsmsi7l3r4&t=34s, around minute: 10:00)

The error appears during this POST request:

Content-Type: application/json

{
  "username": "Kyle",
}

You can find the full code up to that point here: https://github.com/emanuelefavero/json-web-tokens

There are 3 main files to watch for:

server.js
.env (I left the .env file in the github repository)
request.rest (I used this file to make POST request but you can use POSTMAN or other methods)

The error seems to be in server.js, specifically in the express-JWT method:

app.post('/login', (req, res) => {
    // Authenticate User
    // Create json web token
    const username = req.body.username
    const user = { name: username }

    const accessToken = jwt.sign(user, process.env.ACCESS_TOKEN_SECRET)
    console.log(accessToken)
    res.json({ accessToken: accessToken })
})

The GET request is working fine.

While I'm trying to fix this error I'll still respond to any questions and provide project details if needed. Thank you.

Full Error Message:

SyntaxError: Unexpected token } in JSON at position 24
    at JSON.parse (<anonymous>)
    at parse (/Users/arch0n/Desktop/JWT/json-web-token/node_modules/body-parser/lib/types/json.js:89:19)
    at /Users/arch0n/Desktop/JWT/json-web-token/node_modules/body-parser/lib/read.js:128:18
    at AsyncResource.runInAsyncScope (node:async_hooks:199:9)
    at invokeCallback (/Users/arch0n/Desktop/JWT/json-web-token/node_modules/raw-body/index.js:231:16)
    at done (/Users/arch0n/Desktop/JWT/json-web-token/node_modules/raw-body/index.js:220:7)
    at IncomingMessage.onEnd (/Users/arch0n/Desktop/JWT/json-web-token/node_modules/raw-body/index.js:280:7)
    at IncomingMessage.emit (node:events:402:35)
    at endReadableNT (node:internal/streams/readable:1343:12)
    at processTicksAndRejections (node:internal/process/task_queues:83:21)

CodePudding user response：

Chris.

It appears the issue lies in the request you're making. You have a trailing comma in the JSON that you are sending in your request.

If you are new to using JSON & JavaScript, just try to remember that JavaScript objects !== JSON.

In JS Objects, you can have trailing commas. However, in JSON it will cause issues.

Hope this helps.