src/Twitter/Http.hs

   1 module Twitter.Http (
   2   get_user_new_statuses,
   3   get_user_timeline,
   4   http_get
   5   )
   6 where
   7
   8 import qualified Data.ByteString.Lazy as B
   9 import qualified Data.ByteString.Char8 as BC
  10 import qualified Data.Conduit as C
  11 import Data.Conduit.Binary (sinkLbs)
  12 import Network.HTTP.Conduit
  13 import Web.Authenticate.OAuth (
  14   OAuth(..),
  15   Credential,
  16   newCredential,
  17   newOAuth,
  18   signOAuth)
  19
  20 import Configuration (Cfg(..))
  21
  22 -- |The API URL of username's timeline.
  23 --
  24 -- See,
  25 --
  26 --   <https://dev.twitter.com/docs/api/1.1/get/statuses/user_timeline>
  27 --
  28 user_timeline_url :: String -> String
  29 user_timeline_url username =
  30   concat [ "https://api.twitter.com/",
  31            "1.1/",
  32            "statuses/",
  33            "user_timeline.json?",
  34            "screen_name=",
  35            username,
  36            "&include_rts=true&",
  37            "count=10" ]
  38
  39
  40 -- | Given username's last status id, constructs the API URL for
  41 --   username's new statuses. Essentially, 'user_timeline_url' with a
  42 --   "since_id" parameter tacked on.
  43 user_new_statuses_url :: String -> Integer -> String
  44 user_new_statuses_url username last_status_id =
  45   url ++ "&since_id=" ++ since_id
  46   where
  47     url = user_timeline_url username
  48     since_id = show last_status_id
  49
  50
  51 -- | Return's username's timeline.
  52 get_user_timeline :: Cfg -> String -> IO B.ByteString
  53 get_user_timeline cfg username = do
  54   let uri = user_timeline_url username
  55   http_get cfg uri
  56
  57
  58 -- | Returns the JSON representing all of username's statuses that are
  59 --   newer than last_status_id.
  60 get_user_new_statuses :: Cfg -> String -> Integer -> IO B.ByteString
  61 get_user_new_statuses cfg username last_status_id = do
  62   let uri = user_new_statuses_url username last_status_id
  63   http_get cfg uri
  64
  65
  66 -- | Retrieve a URL, or crash.
  67 http_get :: Cfg -> String -> IO B.ByteString
  68 http_get cfg url = do
  69   manager <- newManager def
  70   request <- parseUrl url
  71
  72   C.runResourceT $ do
  73     signed_request <- signOAuth oauth credential request
  74     response <- http signed_request manager
  75     responseBody response C.$$+- sinkLbs
  76
  77   where
  78     consumer_key' = BC.pack (consumer_key cfg)
  79     consumer_secret' = BC.pack (consumer_secret cfg)
  80     access_token' = BC.pack (access_token cfg)
  81     access_secret' = BC.pack (access_secret cfg)
  82
  83     oauth :: OAuth
  84     oauth = newOAuth {
  85               oauthConsumerKey = consumer_key',
  86               oauthConsumerSecret = consumer_secret'
  87             }
  88
  89     credential :: Credential
  90     credential = newCredential access_token' access_secret'