Package

purescript-httpure-contrib-biscotti

Repository
drewolson/purescript-httpure-contrib-biscotti
License
MIT
Uploaded by
drewolson
Published on
2019-09-13

Documentation is on Pursuit.

This library provides a middleware that uses Biscotti.Cookie and Biscotti.Session to add session handling to an HTTPure application. The Biscotti.middleware function requires a session store and then behaves similar to other HTTPure middleware.

Suppose the type of your session is:

type Session = { currentUser :: String }

Note that any type which implements EncodeJson and DecodeJson from Argonaut can be used as your session type.

The primary difference from other middleware is that Biscotti.middleware expects the next middleware in the stack to receive a Maybe Session along with the HTTPure.Request. It expects the return type to be an MonadAff m => m (Tuple HTTPure.Response (Maybe Session)) rather than just a m HTTPure.Response.

If you return Nothing for your Session, your session will be destroyed. If you return a Just Session, your session will be created if it doesn't currently exist, otherwise it will be updated.

Here's a small example application:

import Biscotti.Session as Session
import HTTPure.Contrib.Biscotti as Biscotti

type Session = { currentUser :: String }

router :: Maybe Session -> HTTPure.Request -> Aff (Tuple HTTPure.Response (Maybe Session))
router session req = do
  case req of
    { path: ["login"] } -> do
      response <- HTTPure.ok "login"
      pure $ Tuple response (Just { currentUser: "Drew" })

    { path: ["logout"] } -> do
      response <- HTTPure.ok "logout"
      pure $ Tuple response Nothing

    _ -> do
      response <- HTTPure.ok "hello"
      pure $ Tuple response session

main :: Effect Unit
main = launchAff_ do
  let cookieName = "_test"
  store <- liftEffect $ Session.memoryStore cookieName
  let middleware = Biscotti.middleware cookieName store

  liftEffect $ HTTPure.server (middleware router) do
    log "Server running"

In a larger application, you may prefer to have another layer of middleware that places the Session in a StateT to make it easier to access and modify within your router.