yesod-auth-oauth2/src/Yesod/Auth/OAuth2/Slack.hs
2023-04-05 22:11:56 +00:00

76 lines
2.1 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
-- |
-- OAuth2 plugin for https://slack.com/
--
-- * Authenticates against slack
-- * Uses slack user id as credentials identifier
--
module Yesod.Auth.OAuth2.Slack
( SlackScope(..)
, oauth2Slack
, oauth2SlackScoped
) where
import Yesod.Auth.OAuth2.Prelude
import Network.HTTP.Client
(httpLbs, parseUrlThrow, responseBody, setQueryString)
import Yesod.Auth.OAuth2.Exception as YesodOAuth2Exception
data SlackScope
= SlackBasicScope
| SlackEmailScope
| SlackTeamScope
| SlackAvatarScope
scopeText :: SlackScope -> Text
scopeText SlackBasicScope = "identity.basic"
scopeText SlackEmailScope = "identity.email"
scopeText SlackTeamScope = "identity.team"
scopeText SlackAvatarScope = "identity.avatar"
newtype User = User Text
instance FromJSON User where
parseJSON = withObject "User" $ \root -> do
o <- root .: "user"
User <$> o .: "id"
pluginName :: Text
pluginName = "slack"
defaultScopes :: [SlackScope]
defaultScopes = [SlackBasicScope]
oauth2Slack :: YesodAuth m => Text -> Text -> AuthPlugin m
oauth2Slack = oauth2SlackScoped defaultScopes
oauth2SlackScoped
:: YesodAuth m => [SlackScope] -> Text -> Text -> AuthPlugin m
oauth2SlackScoped scopes clientId clientSecret =
authOAuth2 pluginName oauth2 $ \manager token -> do
let param = encodeUtf8 $ atoken $ accessToken token
req <- setQueryString [("token", Just param)]
<$> parseUrlThrow "https://slack.com/api/users.identity"
userResponse <- responseBody <$> httpLbs req manager
either
(throwIO . YesodOAuth2Exception.JSONDecodingError pluginName)
(\(User userId) -> pure Creds
{ credsPlugin = pluginName
, credsIdent = userId
, credsExtra = setExtra token userResponse
}
)
$ eitherDecode userResponse
where
oauth2 = OAuth2
{ oauth2ClientId = clientId
, oauth2ClientSecret = Just clientSecret
, oauth2AuthorizeEndpoint =
"https://slack.com/oauth/authorize"
`withQuery` [scopeParam "," $ map scopeText scopes]
, oauth2TokenEndpoint = "https://slack.com/api/oauth.access"
, oauth2RedirectUri = Nothing
}