Overhaul metadata merging and add 'ghcup config add-release-channel URI'

lib/GHCup/Download.hs

@@ -121,28 +121,25 @@ getDownloadsF = do
   Settings { urlSource } <- lift getSettings
   case urlSource of
     GHCupURL -> liftE $ getBase ghcupURL
-    (OwnSource url) -> liftE $ getBase url
+    (OwnSource exts) -> do
+      ext  <- liftE $ mapM (either pure getBase) exts
+      mergeGhcupInfo ext
     (OwnSpec av) -> pure av
-    (AddSource (Left ext)) -> do
+    (AddSource exts) -> do
       base <- liftE $ getBase ghcupURL
-      pure (mergeGhcupInfo base ext)
-    (AddSource (Right uri)) -> do
-      base <- liftE $ getBase ghcupURL
-      ext  <- liftE $ getBase uri
-      pure (mergeGhcupInfo base ext)
+      ext  <- liftE $ mapM (either pure getBase) exts
+      mergeGhcupInfo (base:ext)
 
-    where
-
-  mergeGhcupInfo :: GHCupInfo -- ^ base to merge with
-                 -> GHCupInfo -- ^ extension overwriting the base
-                 -> GHCupInfo
-  mergeGhcupInfo (GHCupInfo tr base base2) (GHCupInfo _ ext ext2) =
-    let newDownloads = M.mapWithKey (\k a -> case M.lookup k ext of
-                                        Just a' -> M.union a' a
-                                        Nothing -> a
-                                    ) base
-        newGlobalTools = M.union base2 ext2
-    in GHCupInfo tr newDownloads newGlobalTools
+ where
+  mergeGhcupInfo :: MonadFail m
+                 => [GHCupInfo]
+                 -> m GHCupInfo
+  mergeGhcupInfo [] = fail "mergeGhcupInfo: internal error: need at least one GHCupInfo"
+  mergeGhcupInfo xs@(GHCupInfo{}: _) =
+    let newDownloads   = M.unionsWith (M.unionWith (\_ b2 -> b2)) (_ghcupDownloads   <$> xs)
+        newGlobalTools = M.unionsWith (\_ a2 -> a2              ) (_globalTools      <$> xs)
+        newToolReqs    = M.unionsWith (M.unionWith (\_ b2 -> b2)) (_toolRequirements <$> xs)
+    in pure $ GHCupInfo newToolReqs newDownloads newGlobalTools
 
 
 yamlFromCache :: (MonadReader env m, HasDirs env) => URI -> m FilePath

lib/GHCup/Types.hs

@@ -286,9 +286,9 @@ instance Pretty TarDir where
 
 -- | Where to fetch GHCupDownloads from.
 data URLSource = GHCupURL
-               | OwnSource URI
+               | OwnSource [Either GHCupInfo URI] -- ^ complete source list
                | OwnSpec GHCupInfo
-               | AddSource (Either GHCupInfo URI) -- ^ merge with GHCupURL
+               | AddSource [Either GHCupInfo URI] -- ^ merge with GHCupURL
                deriving (GHC.Generic, Show)
 
 instance NFData URLSource

lib/GHCup/Types/JSON.hs

@@ -79,6 +79,38 @@ instance FromJSON Tag where
 instance ToJSON URI where
   toJSON = toJSON . E.decodeUtf8With E.lenientDecode . serializeURIRef'
 
+instance FromJSON URLSource where
+  parseJSON v =
+        parseGHCupURL v
+    <|> parseOwnSourceLegacy v
+    <|> parseOwnSourceNew1 v
+    <|> parseOwnSourceNew2 v
+    <|> parseOwnSpec v
+    <|> legacyParseAddSource v
+    <|> newParseAddSource v
+   where
+    parseOwnSourceLegacy = withObject "URLSource" $ \o -> do
+      r :: URI <- o .: "OwnSource"
+      pure (OwnSource [Right r])
+    parseOwnSourceNew1 = withObject "URLSource" $ \o -> do
+      r :: [URI] <- o .: "OwnSource"
+      pure (OwnSource (fmap Right r))
+    parseOwnSourceNew2 = withObject "URLSource" $ \o -> do
+      r :: [Either GHCupInfo URI] <- o .: "OwnSource"
+      pure (OwnSource r)
+    parseOwnSpec = withObject "URLSource" $ \o -> do
+      r :: GHCupInfo <- o .: "OwnSpec"
+      pure (OwnSpec r)
+    parseGHCupURL = withObject "URLSource" $ \o -> do
+      _ :: [Value] <- o .: "GHCupURL"
+      pure GHCupURL
+    legacyParseAddSource = withObject "URLSource" $ \o -> do
+      r :: Either GHCupInfo URI <- o .: "AddSource"
+      pure (AddSource [r])
+    newParseAddSource = withObject "URLSource" $ \o -> do
+      r :: [Either GHCupInfo URI] <- o .: "AddSource"
+      pure (AddSource r)
+
 instance FromJSON URI where
   parseJSON = withText "URL" $ \t ->
     case parseURI strictURIParserOptions (encodeUtf8 t) of
@@ -314,7 +346,7 @@ deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''Requir
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''DownloadInfo
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''VersionInfo
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''GHCupInfo
-deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''URLSource
+deriveToJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''URLSource
 deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''Key
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "k-") . T.pack . kebab $ str' } ''UserKeyBindings
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "u-") . T.pack . kebab $ str' } ''UserSettings