Hi! I need to fetch the raw JWT accessToken from t...

# ktor

[hellman]

Hi! I need to fetch the raw JWT accessToken from the current call in my Ktor server. Anyone know how I can do that? I got the Authentication installed and jwt() setup, so I can wrap my endpoint with authenticate { }, but now I need to take the accessToken and pass it on to a different service (not HTTP).

[Aleksei Tirman [JB]]

You can decode the JWT with the following code:

get {
    val jwt = JWT
        .require(Algorithm.HMAC256("secret"))
        .withAudience("audience")
        .withIssuer("issuer")
        .build()
    val auth = call.request.headers[HttpHeaders.Authorization] ?: return@get
    val authHeader = parseAuthorizationHeader(auth)
    if (authHeader is HttpAuthHeader.Single) {
        val decodedJWT = jwt.verify(authHeader.blob)
    }
}

[hellman]

Ok, I want the raw accessToken. Not the decoded one. I can ge that from call.principal()

[Tian Tian098]

I just ended up implementing it by myself.

install(Authentication) {
  bearer {
    authenticate { (token) ->
      // Parse the JWT and return something
    }
}

[hellman]

Yes, but that is not inside a call.

[Aleksei Tirman [JB]]

Can you share the code of your current implementation which obtains the access token?

[hellman]

Basically this:

fun Headers.getAccessToken() = this["Authorization"]?.removePrefix("Bearer ")

It works, and I'm fine if this is what I have to use.

The reason I need this is to propagate the JWT when I call other services.