Auth middleware for JWT:s

jwt-auth.js

// `jwt` is the encoded JSON Web Token
// `token` is the decoded jwt

// jwtFromRequest(req: Request):      String
// algorithmFromToken(token: Object): String 
// keyFromToken(token: Object):       Promise<key: string>

const auth = fucntion({ jwtFromRequest, keyFromToken, algorithmFromToken }) { 
  return (req, res, next) => {
    const jwt = jwtFromRequest(req)
    const token = jws.decode(jwt)

    if (!token) next(new Error("Unauthorized"))

    keyFromToken(token)
      .then(key => {
        if (jws.verify(jwt, algorithmFromToken(token), key)) {
          // should check expiry and make refresh here
          next()
        } else {
          next(new Error("Unauthorized"))
        }
      })
      .catch(error => {
        console.error(error)
        next(new Error("Unauthorized"))
      })
  }
}