today response decoding

app/DataTypes.hs

@@ -0,0 +1,82 @@
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE OverloadedStrings #-} --needed for ByteString arguments
+module DataTypes where
+import Data.Aeson
+import GHC.Generics
+import qualified Data.ByteString.Lazy.Char8 as BL
+
+
+data Location = Location
+  { name :: String
+  , region :: String
+  , country :: String
+  , lat :: Float
+  , lon :: Float
+  , tz_id :: String
+  , localtime_epoch :: Int
+  , localtime :: String
+  } deriving (Show, Generic)
+
+
+data Current = Current
+  { temp_c :: Float
+  } deriving (Show, Generic)
+
+
+data TodayResponse = TodayResponse
+  { location :: Location
+  , current :: Current
+  } deriving (Show, Generic)
+
+
+data Day = Day
+  { avgtemp_c :: Float
+  } deriving (Show, Generic)
+
+
+data ForecastDay = ForecastDay
+  { day :: Day
+  } deriving (Show, Generic)
+
+
+data Forecast = Forecast
+  { forecastday :: [ForecastDay]
+  } deriving (Show, Generic)
+
+
+-- data YesterdayResponse = YesterdayResponse
+--   { location :: Location
+--   , forecast :: Forecast
+--   } deriving (Show, Generic)
+
+
+instance FromJSON Location
+instance ToJSON Location
+instance FromJSON Current
+instance ToJSON Current
+instance FromJSON TodayResponse
+instance ToJSON TodayResponse
+instance FromJSON Day
+instance ToJSON Day
+instance FromJSON ForecastDay
+instance ToJSON ForecastDay
+instance FromJSON Forecast
+instance ToJSON Forecast
+-- instance FromJSON YesterdayResponse
+-- instance ToJSON YesterdayResponse
+
+
+todayDecode :: BL.ByteString -> IO TodayResponse
+todayDecode jsonBody = do
+    let decoded = decode jsonBody :: Maybe TodayResponse
+    case decoded of
+        Just decoded -> return decoded
+        Nothing -> error "Invalid JSON"
+
+
+-- yesterdayDecode :: BL.ByteString -> IO YesterdayResponse
+-- yesterdayDecode jsonBody = do
+--     let decoded = decode jsonBody :: Maybe YesterdayResponse
+--     case decoded of
+--         Just decoded -> return decoded
+--         Nothing -> error "Invalid JSON"

app/Main.hs

@@ -1,9 +1,11 @@
 {-# LANGUAGE OverloadedStrings #-} --needed for ByteString arguments
 import Network.HTTP.Simple
 import System.Environment (lookupEnv)
-import Plot
 import Data.ByteString.UTF8 (fromString) --to convert acquired API key to ByteString
-import Data.Time
+import Data.Time as T
+
+import Plot
+import DataTypes
 
 
 data WhichDay = Yesterday | Today | Tomorrow
@@ -30,20 +32,23 @@ main = do
         let todayDate = formatDate currentDate
         let tomorrowDate = formatDate $ addDays 1 currentDate
 
-        let yesterdayRequest = apiRequestBuilder apiKey Yesterday city yesterdayDate
-        yesterdayResponse <- httpLBS yesterdayRequest
-        putStrLn $ show yesterdayRequest
-        putStrLn $ show $ getResponseStatusCode yesterdayResponse
+        -- let yesterdayRequest = apiRequestBuilder apiKey Yesterday city yesterdayDate
+        -- yesterdayResponse <- httpLBS yesterdayRequest
+        -- print $ getResponseStatusCode yesterdayResponse
+
+        -- yesterdayDecoded <- yesterdayDecode $ getResponseBody yesterdayResponse
+        -- print yesterdayDecoded
 
         let todayRequest = apiRequestBuilder apiKey Today city todayDate
         todayResponse <- httpLBS todayRequest
-        putStrLn $ show todayRequest
-        putStrLn $ show $ getResponseStatusCode todayResponse
+        print $ getResponseStatusCode todayResponse
 
-        let tomorrowRequest = apiRequestBuilder apiKey Tomorrow city tomorrowDate
-        tomorrowResponse <- httpLBS tomorrowRequest
-        putStrLn $ show tomorrowRequest
-        putStrLn $ show $ getResponseStatusCode tomorrowResponse
+        todayDecoded <- todayDecode $ getResponseBody todayResponse
+        print todayDecoded
+
+        -- let tomorrowRequest = apiRequestBuilder apiKey Tomorrow city tomorrowDate
+        -- tomorrowResponse <- httpLBS tomorrowRequest
+        -- print $ getResponseStatusCode tomorrowResponse
 
     --apiResponse <- httpJSON "http://httpbin.org/get" :: IO (Response ()) -- specifying type as httpJSON return value is ambigious
 
@@ -91,7 +96,7 @@ apiRequestBuilder apiKey day city date =
                     }
 
 
-getCurrentDate :: IO Day
+getCurrentDate :: IO T.Day
 getCurrentDate = do
     currentTime <- getCurrentTime
     timeZone <- getCurrentTimeZone
@@ -100,5 +105,5 @@ getCurrentDate = do
     return currentDate
 
 
-formatDate :: Day -> String
+formatDate :: T.Day -> String
 formatDate = formatTime defaultTimeLocale "%Y-%m-%d"

profun.cabal

@@ -59,6 +59,7 @@ executable profun
 
     -- Modules included in this executable, other than Main.
     other-modules:    Plot
+                      DataTypes
 
     -- LANGUAGE extensions used by modules in this package.
     -- other-extensions: