yesod-auth-oauth2/Yesod/Auth/OAuth2.hs
2014-02-15 15:23:58 -05:00

84 lines
2.9 KiB
Haskell

{-# LANGUAGE OverloadedStrings, QuasiQuotes #-}
module Yesod.Auth.OAuth2
( authOAuth2
, oauth2Url
, oauth2Google
, oauth2Learn
, module Network.OAuth.OAuth2
) where
import Control.Monad.IO.Class
import Data.ByteString (ByteString)
import Data.Text (Text)
import Data.Text.Encoding (decodeUtf8With, encodeUtf8)
import Data.Text.Encoding.Error (lenientDecode)
import Yesod.Auth
import Yesod.Form
import Yesod.Core
import Network.OAuth.OAuth2
oauth2Url :: Text -> AuthRoute
oauth2Url name = PluginR name ["forward"]
authOAuth2 :: YesodAuth m
=> Text -- ^ Service name
-> OAuth2 -- ^ Service details
-- | This function defines how to take an @'AccessToken'@ and
-- retrive additional information about the user, to be set
-- in the session as @'Creds'@. Usually this means a second
-- authorized request to @api/me.json@.
-> (AccessToken -> IO (Creds m))
-> AuthPlugin m
authOAuth2 name oauth mkCreds = AuthPlugin name dispatch login
where
url = PluginR name ["callback"]
withCallback = do
tm <- getRouteToParent
render <- lift $ getUrlRender
return $ oauth { oauthCallback = Just $ encodeUtf8 $ render $ tm url }
dispatch "GET" ["forward"] = do
authUrl <- fmap (bsToText . authorizationUrl) withCallback
lift $ redirect authUrl
dispatch "GET" ["callback"] = do
code <- lift $ runInputGet $ ireq textField "code"
oauth' <- withCallback
result <- liftIO $ fetchAccessToken oauth' (encodeUtf8 code)
case result of
Left _ -> permissionDenied "Unable to retreive OAuth2 token"
Right token -> do
creds <- liftIO $ mkCreds token
lift $ setCreds True creds
dispatch _ _ = notFound
login tm = do
render <- getUrlRender
let oaUrl = render $ tm $ oauth2Url name
[whamlet| <a href=#{oaUrl}>Login via #{name} |]
oauth2Google :: Text -> Text -> OAuth2
oauth2Google clientId clientSecret = OAuth2
{ oauthClientId = encodeUtf8 clientId
, oauthClientSecret = encodeUtf8 clientSecret
, oauthOAuthorizeEndpoint = "https://accounts.google.com/o/oauth2/auth"
, oauthAccessTokenEndpoint = "https://accounts.google.com/o/oauth2/token"
, oauthCallback = Nothing
}
oauth2Learn :: Text -> Text -> OAuth2
oauth2Learn clientId clientSecret = OAuth2
{ oauthClientId = encodeUtf8 clientId
, oauthClientSecret = encodeUtf8 clientSecret
, oauthOAuthorizeEndpoint = "http://learn.thoughtbot.com/oauth/authorize"
, oauthAccessTokenEndpoint = "http://learn.thoughtbot.com/oauth/token"
, oauthCallback = Nothing
}
bsToText :: ByteString -> Text
bsToText = decodeUtf8With lenientDecode