9 files changed, 240 insertions, 0 deletions
diff --git a/lib/Web/OpenWeatherMap/API.hs b/lib/Web/OpenWeatherMap/API.hs
new file mode 100644
index 0000000..0c1e282
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/API.hs
@@ -0,0 +1,45 @@
+{-|
+Direct API functions.
+For API key (a.k.a appid) refer to <http://openweathermap.org/appid>.
+-}
+
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE TypeOperators #-}
+
+module Web.OpenWeatherMap.API (
+  weatherByName,
+  weatherByCoord
+) where
+
+import Data.Proxy (Proxy(..))
+
+import Servant.API ((:>), (:<|>)(..), JSON, Get, QueryParam)
+import Servant.Client (client)
+import Servant.Common.Req (ClientM)
+
+import Web.OpenWeatherMap.Types.CurrentWeather (CurrentWeather)
+
+
+type GetCurrentWeather = AppId :> Get '[JSON] CurrentWeather
+type AppId = QueryParam "appid" String
+
+type API
+     = "weather" :> QueryParam "q" String :> GetCurrentWeather
+  :<|> "weather" :> QueryParam "lat" Double :> QueryParam "lon" Double
+                 :> GetCurrentWeather
+
+-- | Request current weather in the city.
+weatherByName
+  :: Maybe String  -- ^ City name, e. g. \"Moscow\" or \"Moscow,ru\".
+  -> Maybe String  -- ^ API key.
+  -> ClientM CurrentWeather
+
+-- | Request current weather at the geographic coordinates (in decimal degrees).
+weatherByCoord
+  :: Maybe Double  -- ^ Latitude, e. g. 55.7522200 for Moscow.
+  -> Maybe Double  -- ^ Longitude, e. g. 37.6155600 for Moscow.
+  -> Maybe String  -- ^ API key.
+  -> ClientM CurrentWeather
+
+weatherByName :<|> weatherByCoord = client (Proxy :: Proxy API)
+
diff --git a/lib/Web/OpenWeatherMap/Client.hs b/lib/Web/OpenWeatherMap/Client.hs
new file mode 100644
index 0000000..7804ef2
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Client.hs
@@ -0,0 +1,49 @@
+{-|
+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"
+
diff --git a/lib/Web/OpenWeatherMap/Types/Clouds.hs b/lib/Web/OpenWeatherMap/Types/Clouds.hs
new file mode 100644
index 0000000..78a6e97
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/Clouds.hs
@@ -0,0 +1,16 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.Clouds (
+  Clouds(..)
+) where
+
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+ 
+
+data Clouds = Clouds
+  { all :: Double
+  } deriving (Show, Generic, FromJSON)
+
diff --git a/lib/Web/OpenWeatherMap/Types/Coord.hs b/lib/Web/OpenWeatherMap/Types/Coord.hs
new file mode 100644
index 0000000..d9a9f21
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/Coord.hs
@@ -0,0 +1,17 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.Coord (
+  Coord(..)
+) where
+
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+
+
+data Coord = Coord
+  { lon :: Double
+  , lat :: Double
+  } deriving (Show, Generic, FromJSON)
+
diff --git a/lib/Web/OpenWeatherMap/Types/CurrentWeather.hs b/lib/Web/OpenWeatherMap/Types/CurrentWeather.hs
new file mode 100644
index 0000000..26572a7
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/CurrentWeather.hs
@@ -0,0 +1,35 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.CurrentWeather (
+  CurrentWeather(..)
+) where
+
+import Prelude hiding (id)
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+
+import Web.OpenWeatherMap.Types.Clouds (Clouds)
+import Web.OpenWeatherMap.Types.Coord (Coord)
+import Web.OpenWeatherMap.Types.Main (Main)
+import Web.OpenWeatherMap.Types.Sys (Sys)
+import Web.OpenWeatherMap.Types.Weather (Weather)
+import Web.OpenWeatherMap.Types.Wind (Wind)
+
+-- | Response to requests for current weather.
+-- Refer to <https://openweathermap.org/current>.
+data CurrentWeather = CurrentWeather
+  { coord :: Coord
+  , weather :: [Weather]
+  , base :: String
+  , main :: Main
+  , wind :: Wind
+  , clouds :: Clouds
+  , dt :: Int
+  , sys :: Sys
+  , id :: Int
+  , name :: String
+  , cod :: Int
+  } deriving (Show, Generic, FromJSON)
+
diff --git a/lib/Web/OpenWeatherMap/Types/Main.hs b/lib/Web/OpenWeatherMap/Types/Main.hs
new file mode 100644
index 0000000..21b1951
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/Main.hs
@@ -0,0 +1,23 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.Main (
+  Main(..)
+) where
+
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+ 
+
+{-# ANN module "HLint: ignore Use camelCase" #-}
+data Main = Main
+  { temp :: Double
+  , pressure :: Double
+  , humidity :: Double
+  , temp_min :: Double
+  , temp_max :: Double
+  , sea_level :: Maybe Double
+  , grnd_level :: Maybe Double
+  } deriving (Show, Generic, FromJSON)
+
diff --git a/lib/Web/OpenWeatherMap/Types/Sys.hs b/lib/Web/OpenWeatherMap/Types/Sys.hs
new file mode 100644
index 0000000..03b223c
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/Sys.hs
@@ -0,0 +1,19 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.Sys (
+  Sys(..)
+) where
+
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+ 
+
+data Sys = Sys
+  { message :: Double
+  , country :: Maybe String
+  , sunrise :: Int
+  , sunset :: Int
+  } deriving (Show, Generic, FromJSON)
+
diff --git a/lib/Web/OpenWeatherMap/Types/Weather.hs b/lib/Web/OpenWeatherMap/Types/Weather.hs
new file mode 100644
index 0000000..090fe0f
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/Weather.hs
@@ -0,0 +1,19 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.Weather (
+  Weather(..)
+) where
+
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+
+
+data Weather = Weather
+  { id :: Int
+  , main :: String
+  , description :: String
+  , icon :: String
+  } deriving (Show, Generic, FromJSON)
+
diff --git a/lib/Web/OpenWeatherMap/Types/Wind.hs b/lib/Web/OpenWeatherMap/Types/Wind.hs
new file mode 100644
index 0000000..8481e62
--- /dev/null
+++ b/lib/Web/OpenWeatherMap/Types/Wind.hs
@@ -0,0 +1,17 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric #-}
+
+module Web.OpenWeatherMap.Types.Wind (
+  Wind(..)
+) where
+
+import GHC.Generics (Generic)
+
+import Data.Aeson (FromJSON)
+ 
+
+data Wind = Wind
+  { speed :: Double
+  , deg :: Double
+  } deriving (Show, Generic, FromJSON)
+