How do I store data in Suave userstate?

Question

I have a web part that handles an OAuth callback request.

After getting access tokens and the user's id from the API, I want to store it in the session state. But when reading the session on subsequent requests, I only see a value for the "Suave.Auth" key.

Here is my web part for the OAuth callback:

path "/oauth" >=> context (fun ctx ->
        let req = ctx.request
        match (req.queryParam "code", req.queryParam "error") with
        | Choice1Of2 code, _ ->
            let id = completeOAuth code
            Authentication.authenticated Session false
            >=> Writers.setUserData "user-id" id
            >=> Redirection.redirect "/view"
        | _, Choice1Of2 error -> RequestErrors.UNAUTHORIZED error)

How can I make sure the "user-id" value is in the session on other requests after this one?

Answer 1

Writers.setUserData stores data in a map that only exists for the duration of the request.

To store data across requests you need to use statefulForSession like this.

let app = 
  statefulForSession >=> context (fun x ->
    match HttpContext.state x with
    | None ->
      // restarted server without keeping the key; set key manually?
      let msg = "Server Key, Cookie Serialiser reset, or Cookie Data Corrupt, "
      + "if you refresh the browser page, you'll have gotten a new cookie."
      OK msg
    | Some store ->
      match store.get "counter" with
      | Some y ->
        store.set "counter" (y + 1) >=> OK (sprintf "Hello %d time(s)" (y + 1))
      | None ->
        store.set "counter" 1 >=> OK "First time")