jwt.verify/decode working only on static strings when using websockets

Hi,

I’m able to generate a token and then send it to a used. The user then stores this locally. Afterwards we call a authentication script to send that token up to the server

Issue: The dynamic token sent is never valid. However, if you console.log this value and hardcode it into the verify function you are able to get a verification and result.

Using this with websockets if that matters.

      this.socket.on('authentication_token', (token) => {
        jwt.verify(token, process.env.JWT_KEY, { algorithm: 'HS512', maxAge: '2d'}, function(err, decode) {
          console.log(decode)
        })
      });

Working example with REST

router.post('/jwt/verify', async (req,res,next) => {
  const { token } = req.body;
  const data = jwt.verify(token, process.env.JWT_KEY, { algorithm: 'HS512', maxAge: '2d'}, function(err, decode) {
    if (err){
      console.log('ERROR', err)
    }
    console.log(decode)
  });
  res.send(true);
});

[FrederickEngelhardt]

@panva looks like I was missing a JSON.parse for the token inside of the websocket response. Adding that did the trick. Thank you!

See code below for reference.

      this.socket.on('authentication_token', (token) => {
        jwt.verify(JSON.parse(token), process.env.JWT_KEY, { algorithm: 'HS512', maxAge: '2d'}, function(err, decode) {
          console.log(decode)
        })
      });

[mirajehossain]

I was also receiving a null value when trying to use jwt.decode(token). Turns out I also needed to parse it jwt.decode(JSON.parse(token))

token already string, but when I parse it using JSON.parse() it throw parse error.