annex.autocommit can be configured via git-annex config

... to control the default behavior in all clones of a repository.

This includes a new Configurable data type, so the GitConfig type indicates
which values can be configured this way.

The implementation should be quite efficient; the config log is only read
once, and only when a Configurable value has not already been set by
git-config.

Indeed, it would be nice in the future to extend this, so that git-config
is itself only read on demand. Some commands may not need to look at the
git configuration at all.

This commit was sponsored by Trenton Cronholm on Patreon.

Annex.hs

@@ -114,7 +114,6 @@ data AnnexState = AnnexState
 	, checkignorehandle :: Maybe (Maybe CheckIgnoreHandle)
 	, forcebackend :: Maybe String
 	, globalnumcopies :: Maybe NumCopies
-	, globalconfig :: Maybe (M.Map String String)
 	, forcenumcopies :: Maybe NumCopies
 	, limit :: ExpandableMatcher Annex
 	, uuidmap :: Maybe UUIDMap
@@ -166,7 +165,6 @@ newState c r = do
 		, checkignorehandle = Nothing
 		, forcebackend = Nothing
 		, globalnumcopies = Nothing
-		, globalconfig = Nothing
 		, forcenumcopies = Nothing
 		, limit = BuildingMatcher []
 		, uuidmap = Nothing

Assistant/Threads/Watcher.hs

@@ -42,6 +42,7 @@ import Annex.InodeSentinal
 import Git.Types
 import Git.FilePath
 import Config
+import Config.GitConfig
 import Utility.ThreadScheduler
 import Logs.Location
 import qualified Database.Keys
@@ -83,7 +84,7 @@ instance E.Exception WatcherControl
 
 watchThread :: NamedThread
 watchThread = namedThread "Watcher" $
-	ifM (liftAnnex $ annexAutoCommit <$> Annex.getGitConfig)
+	ifM (liftAnnex $ getGitConfigVal annexAutoCommit)
 		( runWatcher
 		, waitFor ResumeWatcher runWatcher
 		)

Assistant/WebApp/Configurators/Edit.hs

@@ -43,6 +43,7 @@ import Utility.Gpg
 import Annex.UUID
 import Assistant.Ssh
 import Config
+import Config.GitConfig
 
 import qualified Data.Text as T
 import qualified Data.Map as M
@@ -76,7 +77,7 @@ getRepoConfig uuid mremote = do
 
 	syncable <- case mremote of
 		Just r -> return $ remoteAnnexSync $ Remote.gitconfig r
-		Nothing -> annexAutoCommit <$> Annex.getGitConfig
+		Nothing -> getGitConfigVal annexAutoCommit
 
 	return $ RepoConfig
 		(T.pack $ maybe "here" Remote.name mremote)

Assistant/WebApp/RepoList.hs

@@ -12,7 +12,6 @@ module Assistant.WebApp.RepoList where
 import Assistant.WebApp.Common
 import Assistant.DaemonStatus
 import Assistant.WebApp.Notifications
-import qualified Annex
 import qualified Remote
 import qualified Types.Remote as Remote
 import Remote.List (remoteListRefresh)
@@ -21,6 +20,7 @@ import Logs.Remote
 import Logs.Trust
 import Logs.Group
 import Config
+import Config.GitConfig
 import Git.Remote
 import Assistant.Sync
 import Config.Cost
@@ -152,7 +152,7 @@ repoList reposelector
 			if includeHere reposelector
 				then do
 					r <- RepoUUID <$> getUUID
-					autocommit <- annexAutoCommit <$> Annex.getGitConfig
+					autocommit <- getGitConfigVal annexAutoCommit
 					let hereactions = if autocommit
 						then mkSyncingRepoActions r
 						else mkNotSyncingRepoActions r

CHANGELOG

@@ -7,6 +7,8 @@ git-annex (6.20170102) UNRELEASED; urgency=medium
     taken for --json.
   * vicfg: Include the numcopies configuation.
   * config: New command for storing configuration in the git-annex branch.
+  * annex.autocommit can be configured via git-annex config, to control
+    the default behavior in all clones of a repository.
   * stack.yaml: Update to lts-7.18.
   * Some optimisations to string splitting code.
   * unused: When large files are checked right into git, avoid buffering

Command/Sync.hs

@@ -39,6 +39,7 @@ import qualified Git.Ref
 import qualified Git
 import qualified Remote.Git
 import Config
+import Config.GitConfig
 import Annex.Wanted
 import Annex.Content
 import Command.Get (getKey')
@@ -237,7 +238,7 @@ commit o = stopUnless shouldcommit $ next $ next $ do
 		)
   where
 	shouldcommit = pure (commitOption o)
-		<&&> (annexAutoCommit <$> Annex.getGitConfig)
+		<&&> getGitConfigVal annexAutoCommit
 
 commitMsg :: Annex String
 commitMsg = do

Config.hs

@@ -1,6 +1,6 @@
 {- Git configuration
  -
- - Copyright 2011-2014 Joey Hess <id@joeyh.name>
+ - Copyright 2011-2017 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -24,7 +24,8 @@ data ConfigKey = ConfigKey String
 instance Show ConfigKey where
 	show (ConfigKey s) = s
 
-{- Looks up a setting in git config. -}
+{- Looks up a setting in git config. This is not as efficient as using the
+ - GitConfig type. -}
 getConfig :: ConfigKey -> String -> Annex String
 getConfig (ConfigKey key) d = fromRepo $ Git.Config.get key d
 

Config/GitConfig.hs

@@ -0,0 +1,36 @@
+{- git-annex configuration
+ -
+ - Copyright 2017 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Config.GitConfig where
+
+import Annex.Common
+import qualified Annex
+import Types.GitConfig
+import Git.Types
+import Logs.Config
+
+{- Gets a specific setting from GitConfig. If necessary, loads the
+ - repository-global defaults when the GitConfig does not yet 
+ - have a value. -}
+getGitConfigVal :: (GitConfig -> Configurable a) -> Annex a
+getGitConfigVal f = do
+	v <- f <$> Annex.getGitConfig
+	case v of
+		HasConfig c -> return c
+		DefaultConfig _ -> do
+			r <- Annex.gitRepo
+			m <- loadGlobalConfig
+			let globalgc = extractGitConfig (r { config = m })
+			-- This merge of the repo-global config and the git
+			-- config makes all repository-global default
+			-- values populate the GitConfig with HasConfig
+			-- values, so it will only need to be done once.
+			Annex.changeGitConfig (\gc -> mergeGitConfig gc globalgc)
+			v' <- f <$> Annex.getGitConfig
+			case v' of
+				HasConfig c -> return c
+				DefaultConfig d -> return d

Logs/Config.hs

@@ -1,4 +1,4 @@
-{- git-annex config log
+{- git-annex repository-global config log
  -
  - Copyright 2017 Joey Hess <id@joeyh.name>
  -
@@ -15,7 +15,6 @@ module Logs.Config (
 ) where
 
 import Annex.Common
-import qualified Annex
 import Logs
 import Logs.MapLog
 import qualified Annex.Branch
@@ -44,18 +43,13 @@ unsetGlobalConfig name = do
 	when (curr /= Nothing) $
 		setGlobalConfig' name "" -- set to empty string to unset
 
+-- Reads the global config log every time.
 getGlobalConfig :: ConfigName -> Annex (Maybe ConfigValue)
-getGlobalConfig name = do
-	m <- maybe loadGlobalConfig return
-		=<< Annex.getState Annex.globalconfig
-	return (M.lookup name m)
+getGlobalConfig name = M.lookup name <$> loadGlobalConfig
 
 parseGlobalConfig :: String -> MapLog ConfigName ConfigValue
 parseGlobalConfig = parseMapLog Just Just
 
 loadGlobalConfig :: Annex (M.Map ConfigName ConfigValue)
-loadGlobalConfig = do
-	m <- M.filter (not . null) . simpleMap . parseGlobalConfig
-		<$> Annex.Branch.get configLog
-	Annex.changeState $ \s -> s { Annex.globalconfig = Just m }
-	return m
+loadGlobalConfig = M.filter (not . null) . simpleMap . parseGlobalConfig
+	<$> Annex.Branch.get configLog

Types/GitConfig.hs

@@ -6,8 +6,10 @@
  -}
 
 module Types.GitConfig ( 
+	Configurable(..),
 	GitConfig(..),
 	extractGitConfig,
+	mergeGitConfig,
 	RemoteGitConfig(..),
 	extractRemoteGitConfig,
 ) where
@@ -29,6 +31,14 @@ import Utility.HumanTime
 import Utility.Gpg (GpgCmd, mkGpgCmd)
 import Utility.ThreadScheduler (Seconds(..))
 
+-- | A configurable value, that may not be fully determined yet.
+data Configurable a
+	= HasConfig a
+	-- ^ Value is fully determined.
+	| DefaultConfig a
+	-- ^ A default value is known, but not all config sources
+	-- have been read yet.
+
 {- Main git-annex settings. Each setting corresponds to a git-config key
  - such as annex.foo -}
 data GitConfig = GitConfig
@@ -46,7 +56,7 @@ data GitConfig = GitConfig
 	, annexDelayAdd :: Maybe Int
 	, annexHttpHeaders :: [String]
 	, annexHttpHeadersCommand :: Maybe String
-	, annexAutoCommit :: Bool
+	, annexAutoCommit :: Configurable Bool
 	, annexDebug :: Bool
 	, annexWebOptions :: [String]
 	, annexQuviOptions :: [String]
@@ -93,7 +103,8 @@ extractGitConfig r = GitConfig
 	, annexDelayAdd = getmayberead (annex "delayadd")
 	, annexHttpHeaders = getlist (annex "http-headers")
 	, annexHttpHeadersCommand = getmaybe (annex "http-headers-command")
-	, annexAutoCommit = getbool (annex "autocommit") True
+	, annexAutoCommit = configurable True $ 
+		getmaybebool (annex "autocommit")
 	, annexDebug = getbool (annex "debug") False
 	, annexWebOptions = getwords (annex "web-options")
 	, annexQuviOptions = getwords (annex "quvi-options")
@@ -133,10 +144,26 @@ extractGitConfig r = GitConfig
 	getlist k = Git.Config.getList k r
 	getwords k = fromMaybe [] $ words <$> getmaybe k
 
+	configurable d Nothing = DefaultConfig d
+	configurable _ (Just v) = HasConfig v
+
 	annex k = "annex." ++ k
 			
 	onemegabyte = 1000000
 
+{- Merge a GitConfig that comes from git-config with one containing
+ - repository-global defaults. -}
+mergeGitConfig :: GitConfig -> GitConfig -> GitConfig
+mergeGitConfig gitconfig repoglobals = gitconfig
+	{ annexAutoCommit = merge annexAutoCommit
+	}
+  where
+	merge f = case f gitconfig of
+		HasConfig v -> HasConfig v
+		DefaultConfig d -> case f repoglobals of
+			HasConfig v -> HasConfig v
+			DefaultConfig _ -> HasConfig d
+
 {- Per-remote git-annex settings. Each setting corresponds to a git-config
  - key such as <remote>.annex-foo, or if that is not set, a default from
  - annex.foo -}

doc/git-annex-config.mdwn

@@ -25,9 +25,12 @@ Only a few make sense to be able to set such that all clones of a
 repository see the setting, and so git-annex only looks for these:
 
 These settings can be overridden on a per-repository basis using
-`git config`:
+`git config`.
 
-None yet!
+* `annex.autocommit`
+
+  Set to false to prevent the git-annex assistant and git-annex sync
+  from automatically committing changes to files in the repository.
 
 # EXAMPLE
 

doc/git-annex.mdwn

@@ -1006,8 +1006,8 @@ Here are all the supported configuration settings.
   Set to false to prevent the git-annex assistant and git-annex sync
   from automatically committing changes to files in the repository.
 
-  To configure the behavior in all repositories, this can be set in
-  [[git-annex-config]].
+  To configure the behavior in all clones of the repository,
+  this can be set in [[git-annex-config]].
 
 * `annex.startupscan`
 

doc/todo/wishlist__58___per-repository_autocommit__61__false.mdwn

@@ -3,3 +3,5 @@ when using git-annex as a minority participant in a repository (eg. because in a
 forgetting to do that explicit configuration results, in one sync command, easily results in an unwanted implicit commit that's pushed across remotes.
 
 could there be a per-repository option (somewhere around .gitattributes, or maybe in the git-annex branch) that disables autocommits for the repository?
+
+> [[done]] --[[Joey]]

git-annex.cabal

@@ -793,6 +793,7 @@ Executable git-annex
     Config
     Config.Cost
     Config.Files
+    Config.GitConfig
     Creds
     Crypto
     Database.Fsck