configuration and docs for tracking exports

Not yet handled by sync or assistant.

This commit was sponsored by Nick Daly on Patreon.

Command/Export.hs

@@ -28,6 +28,7 @@ import Logs.Location
 import Logs.Export
 import Database.Export
 import Messages.Progress
+import Config
 import Utility.Tmp
 
 import qualified Data.ByteString.Lazy as L
@@ -41,16 +42,22 @@ cmd = command "export" SectionCommon
 data ExportOptions = ExportOptions
 	{ exportTreeish :: Git.Ref
 	, exportRemote :: DeferredParse Remote
+	, exportTracking :: Bool
 	}
 
 optParser :: CmdParamsDesc -> Parser ExportOptions
 optParser _ = ExportOptions
 	<$> (Git.Ref <$> parsetreeish)
 	<*> (parseRemoteOption <$> parseToOption)
+	<*> parsetracking
   where
 	parsetreeish = argument str
 		( metavar paramTreeish
 		)
+	parsetracking = switch
+		( long "tracking"
+		<> help ("track changes to the " ++ paramTreeish)
+		)
 
 -- To handle renames which swap files, the exported file is first renamed
 -- to a stable temporary name based on the key.
@@ -75,6 +82,10 @@ seek' o r = do
 	db <- openDb (uuid r)
 	ea <- exportActions r
 	recordExportBeginning (uuid r) new
+	
+	when (exportTracking o) $
+		setConfig (remoteConfig r "export-tracking")
+			(fromRef $ exportTreeish o)
 
 	-- Clean up after incomplete export of a tree, in which
 	-- the next block of code below may have renamed some files to

Config.hs

@@ -18,6 +18,7 @@ import Config.Cost
 import Config.DynamicConfig
 import Types.Availability
 import Git.Types
+import qualified Types.Remote as Remote
 
 type UnqualifiedConfigKey = String
 data ConfigKey = ConfigKey String
@@ -55,6 +56,9 @@ instance RemoteNameable Git.Repo where
 instance RemoteNameable RemoteName where
 	 getRemoteName = id
 
+instance RemoteNameable Remote where
+	getRemoteName = Remote.name
+
 {- A per-remote config setting in git config. -}
 remoteConfig :: RemoteNameable r => r -> UnqualifiedConfigKey -> ConfigKey
 remoteConfig r key = ConfigKey $

Types/GitConfig.hs

@@ -199,6 +199,7 @@ data RemoteGitConfig = RemoteGitConfig
 	, remoteAnnexPush :: Bool
 	, remoteAnnexReadOnly :: Bool
 	, remoteAnnexVerify :: Bool
+	, remoteAnnexExportTracking :: Maybe Git.Ref
 	, remoteAnnexTrustLevel :: Maybe String
 	, remoteAnnexStartCommand :: Maybe String
 	, remoteAnnexStopCommand :: Maybe String
@@ -247,6 +248,8 @@ extractRemoteGitConfig r remotename = do
 		, remoteAnnexPush = getbool "push" True
 		, remoteAnnexReadOnly = getbool "readonly" False
 		, remoteAnnexVerify = getbool "verify" True
+		, remoteAnnexExportTracking = Git.Ref
+			<$> notempty (getmaybe "export-tracking")
 		, remoteAnnexTrustLevel = notempty $ getmaybe "trustlevel"
 		, remoteAnnexStartCommand = notempty $ getmaybe "start-command"
 		, remoteAnnexStopCommand = notempty $ getmaybe "stop-command"

doc/git-annex-export.mdwn

@@ -6,6 +6,8 @@ git-annex export - export content to a remote
 
 git annex export `treeish --to remote`
 
+git annex export `--tracking treeish --to remote`
+
 # DESCRIPTION
 
 Use this command to export a tree of files from a git-annex repository.
@@ -36,6 +38,18 @@ verification of content downloaded from an export. Some types of keys,
 that are not based on checksums, cannot be downloaded from an export.
 And, git-annex will never trust an export to retain the content of a key.
 
+# OPTIONS
+
+* `--to=remote`
+
+  Specify the special remote to export to.
+
+* `--tracking`
+
+  This makes the export track changes that are committed to
+  the branch. `git annex sync --content` and the git-annex assistant
+  will update exports when it commits to the branch they are tracking.
+
 # EXAMPLE
 
 	git annex initremote myexport type=directory directory=/mnt/myexport \
@@ -56,6 +70,10 @@ That updates /mnt/myexport to reflect the renamed file.
 That updates /mnt/myexport, to contain only the files in the "subdir"
 directory of the master branch.
 
+	git annex export --tracking master --to myexport
+
+That makes myexport track changes that are committed to the master branch.
+
 # EXPORT CONFLICTS
 
 If two different git-annex repositories are both exporting different trees
@@ -81,6 +99,8 @@ export`, it will detect the export conflict, and resolve it.
 
 [[git-annex-initremote]](1)
 
+[[git-annex-sync]](1)
+
 # AUTHOR
 
 Joey Hess <id@joeyh.name>

doc/git-annex-sync.mdwn

@@ -82,6 +82,10 @@ by running "git annex sync" on the remote.
   This behavior can be overridden by configuring the preferred content
   of a repository. See [[git-annex-preferred-content]](1).
 
+  When a special remote is configured as an export and is tracking a branch,
+  the export will be updated to the current content of the branch.
+  See [[git-annex-export]](1).
+
 * `--content-of=path` `-C path`
 
   While --content operates on all annexed files in the work tree,

doc/git-annex.mdwn

@@ -1210,6 +1210,14 @@ Here are all the supported configuration settings.
   from remotes. If you trust a remote and don't want the overhead
   of these checksums, you can set this to `false`.
 
+* `remote.<name>.annex-export-tracking`
+
+  When set to a branch name or other treeish, this makes what's exported
+  to the special remote track changes to the branch. See
+  [[git-annex-export]](1). `git-annex sync --content` and the 
+  git-annex assistant update exports when changes have been
+  committed to the tracking branch.
+
 * `remote.<name>.annexUrl`
 
   Can be used to specify a different url than the regular `remote.<name>.url`