Add --metadata-fetching-mode arg, fixes #440

lib/GHCup/Download.hs

@@ -162,17 +162,21 @@ getBase :: ( MonadReader env m
            , MonadMask m
            )
         => URI
-        -> Excepts '[GPGError, DigestError, JSONError, FileDoesNotExistError] m GHCupInfo
+        -> Excepts '[DownloadFailed, GPGError, DigestError, JSONError, FileDoesNotExistError] m GHCupInfo
 getBase uri = do
-  Settings { noNetwork, downloader } <- lift getSettings
+  Settings { noNetwork, downloader, metaMode } <- lift getSettings
 
   -- try to download yaml... usually this writes it into cache dir,
   -- but in some cases not (e.g. when using file://), so we honour
   -- the return filepath, if any
   mYaml <- if noNetwork && view (uriSchemeL' % schemeBSL') uri /= "file" -- for file://, let it fall through
            then pure Nothing
-           else handleIO (\e -> lift (warnCache (displayException e) downloader) >> pure Nothing)
-               . catchE @_ @_ @'[] (\e@(DownloadFailed _) -> lift (warnCache (prettyShow e) downloader) >> pure Nothing)
+           else handleIO (\e -> case metaMode of
+                                  Strict -> throwIO e
+                                  Lax -> lift (warnCache (displayException e) downloader) >> pure Nothing)
+               . catchE @_ @_ @'[DownloadFailed] (\e@(DownloadFailed _) -> case metaMode of
+                   Strict -> throwE e
+                   Lax -> lift (warnCache (prettyShow e) downloader) >> pure Nothing)
                . fmap Just
                . smartDl
                $ uri

lib/GHCup/Types.hs

@@ -297,10 +297,16 @@ instance NFData URLSource
 instance NFData (URIRef Absolute) where
   rnf (URI !_ !_ !_ !_ !_) = ()
 
+data MetaMode = Strict
+              | Lax
+  deriving (Show, Read, Eq, GHC.Generic)
+
+instance NFData MetaMode
 
 data UserSettings = UserSettings
   { uCache       :: Maybe Bool
   , uMetaCache   :: Maybe Integer
+  , uMetaMode    :: Maybe MetaMode
   , uNoVerify    :: Maybe Bool
   , uVerbose     :: Maybe Bool
   , uKeepDirs    :: Maybe KeepDirs
@@ -314,13 +320,14 @@ data UserSettings = UserSettings
   deriving (Show, GHC.Generic)
 
 defaultUserSettings :: UserSettings
-defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
+defaultUserSettings = UserSettings Nothing Nothing 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
+    , uMetaMode = Just metaMode
     , uNoVerify = Just noVerify
     , uVerbose = Just verbose
     , uKeepDirs = Just keepDirs
@@ -346,6 +353,7 @@ fromSettings Settings{..} (Just KeyBindings{..}) =
   in UserSettings {
       uCache = Just cache
     , uMetaCache = Just metaCache
+    , uMetaMode = Just metaMode
     , uNoVerify = Just noVerify
     , uVerbose = Just verbose
     , uKeepDirs = Just keepDirs
@@ -426,6 +434,7 @@ instance NFData LeanAppState
 data Settings = Settings
   { cache            :: Bool
   , metaCache        :: Integer
+  , metaMode         :: MetaMode
   , noVerify         :: Bool
   , keepDirs         :: KeepDirs
   , downloader       :: Downloader
@@ -442,7 +451,7 @@ defaultMetaCache :: Integer
 defaultMetaCache = 300 -- 5 minutes
 
 defaultSettings :: Settings
-defaultSettings = Settings False defaultMetaCache False Never Curl False GHCupURL False GPGNone False Nothing
+defaultSettings = Settings False defaultMetaCache Lax False Never Curl False GHCupURL False GPGNone False Nothing
 
 instance NFData Settings
 

lib/GHCup/Types/JSON.hs

@@ -43,6 +43,7 @@ import qualified Text.Megaparsec               as MP
 import qualified Text.Megaparsec.Char          as MPC
 
 
+deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''MetaMode
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''Architecture
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''LinuxDistro
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''VSep