1 files changed, 49 insertions, 0 deletions
diff --git a/lib/Web/OpenWeatherMap/Client.hs b/lib/Web/OpenWeatherMap/Client.hs
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+++ b/lib/Web/OpenWeatherMap/Client.hs
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+{-|
+High-level client functions perfoming requests to OpenWeatherMap API.
+-}
+module Web.OpenWeatherMap.Client (
+  Location(..),
+  getWeather
+) where
+
+import Network.HTTP.Client (newManager, defaultManagerSettings)
+import Servant.Client (ClientEnv(..), runClientM, ServantError)
+import Servant.Common.BaseUrl (BaseUrl(..), Scheme(..))
+import Servant.Common.Req (ClientM)
+
+import Web.OpenWeatherMap.Types.CurrentWeather (CurrentWeather)
+import qualified Web.OpenWeatherMap.API as API
+
+
+-- | Various way to specify location.
+data Location
+  = Name String          -- ^ City name.
+  | Coord Double Double  -- ^ Geographic coordinates: latitude and longitude.
+
+
+-- | Make a request to OpenWeatherMap API
+--   and return current weather in given location.
+getWeather
+  :: String -- ^ API key.
+  -> Location
+  -> IO (Either ServantError CurrentWeather)
+getWeather appid loc =
+  defaultEnv >>= runClientM (api loc appid)
+
+api
+  :: Location
+  -> String                  -- ^ API key.
+  -> ClientM CurrentWeather
+api (Name city) = API.weatherByName (Just city) . Just
+api (Coord lat lon) = API.weatherByCoord (Just lat) (Just lon) . Just
+
+defaultEnv :: IO ClientEnv
+defaultEnv = do
+  manager <- newManager defaultManagerSettings
+  return $ ClientEnv manager baseUrl
+
+-- XXX openweathermap.org does not support HTTPS,
+-- XXX appid is passed in clear text. Oops.
+baseUrl :: BaseUrl
+baseUrl = BaseUrl Http "api.openweathermap.org" 80 "/data/2.5"
+