Allow to control the metadata cache, fixes #278

lib/GHCup/Download.hs

@@ -242,14 +242,18 @@ getBase uri = do
     e <- liftIO $ doesFileExist json_file
     currentTime <- liftIO getCurrentTime
     Dirs { cacheDir } <- lift getDirs
+    Settings { metaCache } <- lift getSettings
 
        -- for local files, let's short-circuit and ignore access time
     if | scheme == "file" -> liftE $ download uri' Nothing Nothing cacheDir Nothing True
        | e -> do
-          accessTime <- liftIO $ getAccessTime json_file
-
+          accessTime <- fmap utcTimeToPOSIXSeconds $ liftIO $ getAccessTime json_file
+          let sinceLastAccess = utcTimeToPOSIXSeconds currentTime - accessTime
+          let cacheInterval = fromInteger metaCache
+          lift $ logDebug $ "last access was " <> T.pack (show sinceLastAccess) <> " ago, cache interval is " <> T.pack (show cacheInterval)
           -- access time won't work on most linuxes, but we can try regardless
-          if | ((utcTimeToPOSIXSeconds currentTime - utcTimeToPOSIXSeconds accessTime) > 300) ->
+          if | metaCache <= 0 -> dlWithMod currentTime json_file
+             | (sinceLastAccess > cacheInterval) ->
                 -- no access in last 5 minutes, re-check upstream mod time
                 dlWithMod currentTime json_file
              | otherwise -> pure json_file

lib/GHCup/Types.hs

@@ -294,6 +294,7 @@ instance NFData (URIRef Absolute) where
 
 data UserSettings = UserSettings
   { uCache       :: Maybe Bool
+  , uMetaCache   :: Maybe Integer
   , uNoVerify    :: Maybe Bool
   , uVerbose     :: Maybe Bool
   , uKeepDirs    :: Maybe KeepDirs
@@ -306,12 +307,13 @@ data UserSettings = UserSettings
   deriving (Show, GHC.Generic)
 
 defaultUserSettings :: UserSettings
-defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
+defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
 
 fromSettings :: Settings -> Maybe KeyBindings -> UserSettings
 fromSettings Settings{..} Nothing =
   UserSettings {
       uCache = Just cache
+    , uMetaCache = Just metaCache
     , uNoVerify = Just noVerify
     , uVerbose = Just verbose
     , uKeepDirs = Just keepDirs
@@ -335,6 +337,7 @@ fromSettings Settings{..} (Just KeyBindings{..}) =
             }
   in UserSettings {
       uCache = Just cache
+    , uMetaCache = Just metaCache
     , uNoVerify = Just noVerify
     , uVerbose = Just verbose
     , uKeepDirs = Just keepDirs
@@ -410,6 +413,7 @@ instance NFData LeanAppState
 
 data Settings = Settings
   { cache      :: Bool
+  , metaCache  :: Integer
   , noVerify   :: Bool
   , keepDirs   :: KeepDirs
   , downloader :: Downloader
@@ -421,6 +425,12 @@ data Settings = Settings
   }
   deriving (Show, GHC.Generic)
 
+defaultMetaCache :: Integer
+defaultMetaCache = 300 -- 5 minutes
+
+defaultSettings :: Settings
+defaultSettings = Settings False defaultMetaCache False Never Curl False GHCupURL False GPGNone False
+
 instance NFData Settings
 
 data Dirs = Dirs

lib/GHCup/Utils.hs

@@ -111,7 +111,7 @@ import qualified Data.List.NonEmpty            as NE
 -- >>> let lc = LoggerConfig { lcPrintDebug = False, consoleOutter = mempty, fileOutter = mempty, fancyColors = False }
 -- >>> dirs' <- getAllDirs
 -- >>> let installedVersions = [ ([pver|8.10.7|], Nothing), ([pver|8.10.4|], Nothing), ([pver|8.8.4|], Nothing), ([pver|8.8.3|], Nothing) ]
--- >>> let settings = Settings True False Never Curl False GHCupURL True GPGNone False
+-- >>> let settings = Settings True 0 False Never Curl False GHCupURL True GPGNone False
 -- >>> let leanAppState = LeanAppState settings dirs' defaultKeyBindings lc
 -- >>> cwd <- getCurrentDirectory
 -- >>> (Right ref) <- pure $ parseURI strictURIParserOptions $ "file://" <> E.encodeUtf8 (T.pack cwd) <> "/data/metadata/" <> (urlBaseName . view pathL' $ ghcupURL)