uriTokenizer.js

const fs = require('fs');
const config = require('../assets/configs/config');
const jwt = require('jsonwebtoken');
const urlBuilder = require('build-url');

//We use Public/Private key, but you can use Secret (with HMAC algorithm)
let secretOrPrivateKey = fs.readFileSync(config.sslPrivatekey_path);
let secretOrPublicKey = fs.readFileSync(config.sslPublickey_path);

function uriTokenizer(signOptions, verifyOptions){
    // Sign options incluses
    // algorithm, keyid, expiresIn, notBefore, audience, subject, issuer, jwtid, noTimestamp, header, encoding
    this.signOptions= signOptions; 
    
    // Verify options incluses
    // algorithms, audience, clockTimestamp, clockTolerance, issuer, ignoreExpiration, ignoreNotBefore, jwtid, subject
    this.verifyOptions = verifyOptions;
}

//To sign a Uri with any payload provided
uriTokenizer.prototype.signUri = async function (uri, payload){
    let that=this;
    const promise = new Promise(function(resolve, reject) {
        jwt.sign(payload, secretOrPrivateKey, that.signOptions, function(err, token) {
            if(err) 
                return reject(err);

            return resolve(
                urlBuilder(uri, {queryParams: {token: token }}); //append Toekn query string with the Uri
            );
        });
    });
    return await promise;
};

//An async middleware to verify if a token passed is valid & not expired.
uriTokenizer.prototype.verifyUriRequest = async function (req,res,next){
    const token = req.query.token;
    if (!token) //if token is missing
        return res.status(400).json({ message: config.TOKEN_NOT_FOUND_MESSAGE });

    jwt.verify(token, secretOrPublicKey, this.verifyOptions, (err, payload) => {
        //return 403 in case of TokenExpiredError/JsonWebTokenError
        if(err) return res.status(403).json({ message: err.message });
        return next();
    });
};

module.exports = uriTokenizer;