yesod-auth-oauth2/src/Yesod/Auth/OAuth2.hs
2018-07-30 09:10:37 -04:00

88 lines
2.5 KiB
Haskell

{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE QuasiQuotes #-}
-- |
--
-- Generic OAuth2 plugin for Yesod
--
-- See @"Yesod.Auth.OAuth2.GitHub"@ for example usage.
--
module Yesod.Auth.OAuth2
( OAuth2(..)
, FetchCreds
, Manager
, OAuth2Token(..)
, Creds(..)
, oauth2Url
, authOAuth2
, authOAuth2Widget
-- * Reading our @'credsExtra'@ keys
, getAccessToken
, getRefreshToken
, getUserResponse
, getUserResponseJSON
) where
import Control.Error.Util (note)
import Control.Monad ((<=<))
import Data.Aeson (FromJSON, eitherDecode)
import Data.ByteString.Lazy (ByteString, fromStrict)
import Data.Text (Text)
import Data.Text.Encoding (encodeUtf8)
import Network.HTTP.Conduit (Manager)
import Network.OAuth.OAuth2
import Yesod.Auth
import Yesod.Auth.OAuth2.Dispatch
import Yesod.Core.Widget
oauth2Url :: Text -> AuthRoute
oauth2Url name = PluginR name ["forward"]
-- | Create an @'AuthPlugin'@ for the given OAuth2 provider
--
-- Presents a generic @"Login via #{name}"@ link
--
authOAuth2 :: YesodAuth m => Text -> OAuth2 -> FetchCreds m -> AuthPlugin m
authOAuth2 name = authOAuth2Widget [whamlet|Login via #{name}|] name
-- | Create an @'AuthPlugin'@ for the given OAuth2 provider
--
-- Allows passing a custom widget for the login link. See @'oauth2Eve'@ for an
-- example.
--
authOAuth2Widget
:: YesodAuth m
=> WidgetFor m ()
-> Text
-> OAuth2
-> FetchCreds m
-> AuthPlugin m
authOAuth2Widget widget name oauth getCreds =
AuthPlugin name (dispatchAuthRequest name oauth getCreds) login
where
login tm = [whamlet|<a href=@{tm $ oauth2Url name}>^{widget}|]
-- | Read the @'AccessToken'@ from the values set via @'setExtra'@
getAccessToken :: Creds m -> Maybe AccessToken
getAccessToken =
(AccessToken <$>) . lookup "accessToken" . credsExtra
-- | Read the @'RefreshToken'@ from the values set via @'setExtra'@
--
-- N.B. not all providers supply this value.
--
getRefreshToken :: Creds m -> Maybe RefreshToken
getRefreshToken =
(RefreshToken <$>) . lookup "refreshToken" . credsExtra
-- | Read the original profile response from the values set via @'setExtra'@
getUserResponse :: Creds m -> Maybe ByteString
getUserResponse =
(fromStrict . encodeUtf8 <$>) . lookup "userResponse" . credsExtra
-- | @'getUserResponse'@, and decode as JSON
getUserResponseJSON :: FromJSON a => Creds m -> Either String a
getUserResponseJSON =
eitherDecode <=< note "userResponse key not present" . getUserResponse