Unable to get decoded payload of JWT from auth0/express-jwt library

denzel · August 14, 2020, 6:50am

Hello, here is the link! thanks!

Unable to get decoded payload of JWT from auth0/express-jwt library

opened 04:17PM - 13 Aug 20 UTC

closed 01:11PM - 21 Aug 20 UTC

### Description I'm trying to obtain the decoded JWT payload using the `expre…ss-jwt` from `auth0` as a middleware in my expressjs application. For the token to be used for authentication, I have to use a custom `async` function to process the token first before providing it to `express-jwt`. I understand that I can write a custom function under the `getToken` parameter as documented in `express-jwt` as shown below, but it does not work with `async` function. ``` const jwt = require("express-jwt"); const checkJwt = jwt({ secret: 'hello world !', algorithms: ['HS256'], credentialsRequired: false, getToken: function fromHeaderOrQuerystring (req) { if (req.headers.authorization && req.headers.authorization.split(' ')[0] === 'Bearer') { return req.headers.authorization.split(' ')[1]; } else if (req.query && req.query.token) { return req.query.token; } return null; } }); module.exports = checkJwt; ``` To overcome this limitation, I included the `jwt()` as part of a larger middleware function that first process the token, and then providing it to `jwt()`. The unprocessed token is attached to my headers. My code structure is as follows: ``` const myMiddleware = async (req, res, next) => { // Process Token First const processedToken = await functionToProcessToken(req.headers.tokenLocation); // Jwt Authentication jwt({ secret: 'hello world !', algorithms: ['HS256'], credentialsRequired: false, getToken: processedToken }); next(); }); module.exports = myMiddleware; ``` While I'm able to authenticate my routes without any issue, I need to get the decoded JWT payload for further uses. By default, as written in the documentation, the decoded payload should have been attached to `req.user`, but when I try to console.log it, it shows `undefined`. I have also tried adding `requestProperty` but it does not work as well. The documentation for `resultProperty` is not very clear, so I could not get that to work too. I very much appreciate if someone can point me towards right direction to help me achieve the expected outcome for my middleware. Thank you! ### Environment - **Version of this library used:** 5.3.3 - **Version of the platform or framework used, if applicable:** - **Other relevant versions (language, server software, OS, browser):** Ubuntu 18.04 - **Other modules/plugins/libraries that might be involved:** jwts-rsa

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Unable to get decoded payload of JWT from auth0/express-jwt library

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