add git-annex updatecluster command

Seems to work fine, making the right changes to the git-annex branch.

CHANGELOG

@@ -2,7 +2,7 @@ git-annex (10.20240532) UNRELEASED; urgency=medium
 
   * Added git-annex updateproxy command and remote.name.annex-proxy
     configuration.
-  * Added git-annex cluster command and remote.name.annex-cluster-node
+  * Added git-annex updatecluster command and remote.name.annex-cluster-node
     and annex.cluster.name configuration.
   * Fix a bug where interrupting git-annex while it is updating the
     git-annex branch for an export could later lead to git fsck

CmdLine/GitAnnex.hs

@@ -124,6 +124,7 @@ import qualified Command.Smudge
 import qualified Command.FilterProcess
 import qualified Command.Restage
 import qualified Command.Undo
+import qualified Command.UpdateCluster
 import qualified Command.UpdateProxy
 import qualified Command.Version
 import qualified Command.RemoteDaemon
@@ -248,6 +249,7 @@ cmds testoptparser testrunner mkbenchmarkgenerator = map addGitAnnexCommonOption
 	, Command.FilterProcess.cmd
 	, Command.Restage.cmd
 	, Command.Undo.cmd
+	, Command.UpdateCluster.cmd
 	, Command.UpdateProxy.cmd
 	, Command.Version.cmd
 	, Command.RemoteDaemon.cmd

Command/UpdateProxy.hs

@@ -30,7 +30,7 @@ start = startingCustomOutput (ActionItemOther Nothing) $ do
 	rs <- R.remoteList
 	let proxies = S.fromList $ 
 		map (\r -> Proxy (R.uuid r) (R.name r)) $
-			filter (remoteAnnexProxy . R.gitconfig) rs
+			filter (isproxy . R.gitconfig) rs
 	u <- getUUID
 	oldproxies <- fromMaybe mempty . M.lookup u <$> getProxies
 	if oldproxies == proxies
@@ -50,3 +50,5 @@ start = startingCustomOutput (ActionItemOther Nothing) $ do
 					putStrLn $ safeOutput $
 						"Stopped proxying for " ++ proxyRemoteName p
 				_ -> noop
+	
+	isproxy c = remoteAnnexProxy c || not (null (remoteAnnexClusterNode c))

Git/Remote.hs

@@ -68,7 +68,10 @@ makeLegalName s = case filter legal $ replace "/" "_" s of
 	legal '-' = True
 	legal '.' = True
 	legal c = isAlphaNum c
-	
+
+isLegalName :: String -> Bool
+isLegalName s = s == makeLegalName s
+
 data RemoteLocation = RemoteUrl String | RemotePath FilePath
 	deriving (Eq, Show)
 

Git/Types.hs

@@ -84,6 +84,9 @@ instance Default ConfigValue where
 fromConfigKey :: ConfigKey -> String
 fromConfigKey (ConfigKey s) = decodeBS s
 
+fromConfigKey' :: ConfigKey -> S.ByteString
+fromConfigKey' (ConfigKey s) = s
+
 instance Show ConfigKey where
 	show = fromConfigKey
 

Logs/Cluster.hs

@@ -21,7 +21,6 @@ import Types.Cluster
 import Logs
 import Logs.UUIDBased
 import Logs.MapLog
-import Annex.UUID
 
 import qualified Data.Set as S
 import qualified Data.Map as M
@@ -61,10 +60,9 @@ recordCluster clusteruuid nodeuuids = do
 		nodeuuids
 	
 	c <- currentVectorClock
-	u <- getUUID
 	Annex.Branch.change (Annex.Branch.RegardingUUID [fromClusterUUID clusteruuid]) clusterLog $
 		(buildLogNew buildClusterNodeList)
-			. changeLog c u nodeuuids'
+			. changeLog c (fromClusterUUID clusteruuid) nodeuuids'
 			. parseClusterLog
 
 buildClusterNodeList :: S.Set ClusterNodeUUID -> Builder

Logs/Proxy.hs

@@ -85,5 +85,4 @@ parseProxyList = S.fromList <$> many parseword
 -- characters in names, and ensures the name can be used anywhere a usual
 -- git remote name can be used without causing issues.
 validateProxies :: S.Set Proxy -> S.Set Proxy
-validateProxies = S.filter $ \p ->
-	Git.Remote.makeLegalName (proxyRemoteName p) == proxyRemoteName p
+validateProxies = S.filter $ Git.Remote.isLegalName . proxyRemoteName

Types/Cluster.hs

@@ -10,6 +10,7 @@
 module Types.Cluster (
 	ClusterUUID,
 	mkClusterUUID,
+	genClusterUUID,
 	isClusterUUID,
 	fromClusterUUID,
 	ClusterNodeUUID(..),
@@ -32,17 +33,13 @@ import Data.Char
 newtype ClusterUUID = ClusterUUID UUID
 	deriving (Show, Eq, Ord)
 
--- Smart constructor for a ClusterUUID.
---
--- The input UUID can be any regular UUID (eg V4). It is converted to a valid
--- cluster UUID.
+-- Smart constructor for a ClusterUUID. Only allows valid cluster UUIDs.
 mkClusterUUID :: UUID -> Maybe ClusterUUID
-mkClusterUUID (UUID b)
-	| B.length b > 14 = Just $ ClusterUUID $ UUID $
-		"ac" <> B.drop 2 (B.take 14 b) <> "8" <> B.drop 15 b
+mkClusterUUID u
+	| isClusterUUID u = Just (ClusterUUID u)
 	| otherwise = Nothing
-mkClusterUUID NoUUID = Nothing
 
+-- Check if it is a valid cluster UUID.
 isClusterUUID :: UUID -> Bool
 isClusterUUID (UUID b) 
 	| B.take 2 b == "ac" = 
@@ -55,6 +52,15 @@ isClusterUUID (UUID b)
 	eight = fromIntegral (ord '8')
 isClusterUUID _ = False
 
+-- Generates a ClusterUUID from any regular UUID (eg V4). 
+-- It is converted to a valid cluster UUID.
+genClusterUUID :: UUID -> Maybe ClusterUUID
+genClusterUUID (UUID b)
+	| B.length b > 14 = Just $ ClusterUUID $ UUID $
+		"ac" <> B.drop 2 (B.take 14 b) <> "8" <> B.drop 15 b
+	| otherwise = Nothing
+genClusterUUID NoUUID = Nothing
+
 fromClusterUUID :: ClusterUUID -> UUID
 fromClusterUUID (ClusterUUID u) = u
 
@@ -69,3 +75,4 @@ data Clusters = Clusters
 	{ clusterUUIDs :: M.Map ClusterUUID (S.Set ClusterNodeUUID)
 	, clusterNodeUUIDs :: M.Map ClusterNodeUUID (S.Set ClusterUUID)
 	}
+	deriving (Show)

Types/GitConfig.hs

@@ -31,7 +31,7 @@ import qualified Git.Config
 import qualified Git.Construct
 import Git.Types
 import Git.ConfigTypes
-import Git.Remote (isRemoteKey, remoteKeyToRemoteName)
+import Git.Remote (isRemoteKey, isLegalName, remoteKeyToRemoteName)
 import Git.Branch (CommitMode(..))
 import Git.Quote (QuotePath(..))
 import Utility.DataUnits
@@ -156,7 +156,7 @@ data GitConfig = GitConfig
 	, annexPrivateRepos :: S.Set UUID
 	, annexAdviceNoSshCaching :: Bool
 	, annexViewUnsetDirectory :: ViewUnset
-	, annexClusters :: M.Map String ClusterUUID
+	, annexClusters :: M.Map RemoteName ClusterUUID
 	}
 
 extractGitConfig :: ConfigSource -> Git.Repo -> GitConfig
@@ -287,10 +287,8 @@ extractGitConfig configsource r = GitConfig
 		getmaybe (annexConfig "viewunsetdirectory")
 	, annexClusters = 
 		M.mapMaybe (mkClusterUUID . toUUID) $
-		M.mapKeys (drop (B.length clusterprefix) . fromConfigKey) $
-		M.filterWithKey
-			(\(ConfigKey k) _ -> clusterprefix `B.isPrefixOf` k)
-			(config r)
+			M.mapKeys removeclusterprefix $
+				M.filterWithKey isclusternamekey (config r)
 	}
   where
 	getbool k d = fromMaybe d $ getmaybebool k
@@ -316,6 +314,9 @@ extractGitConfig configsource r = GitConfig
 	hereuuid = maybe NoUUID toUUID $ getmaybe (annexConfig "uuid")
 
 	clusterprefix = annexConfigPrefix <> "cluster."
+	isclusternamekey k _ = clusterprefix `B.isPrefixOf` (fromConfigKey' k)
+		&& isLegalName (removeclusterprefix k)
+	removeclusterprefix k = drop (B.length clusterprefix) (fromConfigKey k)
 
 {- Merge a GitConfig that comes from git-config with one containing
  - repository-global defaults. -}
@@ -387,7 +388,7 @@ data RemoteGitConfig = RemoteGitConfig
 	, remoteAnnexMaxGitBundles :: Int
 	, remoteAnnexAllowEncryptedGitRepo :: Bool
 	, remoteAnnexProxy :: Bool
-	, remoteAnnexClusterNode :: Maybe [String]
+	, remoteAnnexClusterNode :: Maybe [RemoteName]
 	, remoteUrl :: Maybe String
 
 	{- These settings are specific to particular types of remotes
@@ -473,7 +474,9 @@ extractRemoteGitConfig r remotename = do
 		, remoteAnnexAllowEncryptedGitRepo = 
 			getbool AllowEncryptedGitRepoField False
 		, remoteAnnexProxy = getbool ProxyField False
-		, remoteAnnexClusterNode = words <$> getmaybe ClusterNodeField
+		, remoteAnnexClusterNode = 
+			(filter isLegalName . words)
+				<$> getmaybe ClusterNodeField
 		, remoteUrl = 
 			case Git.Config.getMaybe (remoteConfig remotename (remoteGitConfigKey UrlField)) r of
 				Just (ConfigValue b)

doc/git-annex-updatecluster.mdwn

@@ -0,0 +1,60 @@
+# NAME
+
+git-annex updatecluster - update records with cluster configuration
+
+# SYNOPSIS
+
+git-annex updatecluster
+
+# DESCRIPTION
+
+A git-annex repository can provide access to its remotes as a unified
+cluster. This allows other repositories to access the cluster as a remote,
+with uploads and downloads distributed amoung the nodes of the cluster,
+according to their preferred content settings.
+
+To configure a repository to serve as a proxy to a cluster, first add
+remotes to the repository that will serve as nodes of the cluster.
+These can be any kind of git-annex remote, including special remotes.
+
+For each remote that will be a node of the cluster, 
+configure `git config remote.name.annex-cluster-node`, setting it to the
+name of the cluster.
+
+Finally, run `git-annex updatecluster` to record the cluster configuration
+in the git-annex branch. That tells other repositories about the cluster.
+
+To later add new nodes to the cluster, or remove existing nodes from the
+cluster, set or unset `remote.name.annex-cluster-node` as desired,
+and run `git-annex updatecluster` again.
+
+Example:
+
+    git config remote.foo.annex-cluster-node mycluster
+    git config remote.bar.annex-cluster-node mycluster
+    git config remote.baz.annex-cluster-node mycluster
+    git-annex updatecluster
+
+Suppose, for example, that remote "bigserver" has had those command run in
+it. Then after pulling from "bigserver", git-annex will know about an
+additional remote, "bigserver-mycluster", which can be used like any other
+remote but is an interface to the cluster as a whole. The individual cluster
+nodes will also be proxied as remotes, eg "bigserver-foo".
+
+Clusters can only be accessed via ssh.
+
+# OPTIONS
+
+* The [[git-annex-common-options]](1) can be used.
+
+# SEE ALSO
+
+[[git-annex]](1)
+[[git-annex-preferred-content]](1)
+[[git-annex-updateproxy]](1)
+
+# AUTHOR
+
+Joey Hess <id@joeyh.name>
+
+Warning: Automatically converted into a man page by mdwn2man. Edit with care.

doc/git-annex-updateproxy.mdwn

@@ -24,7 +24,9 @@ configuration.
 Suppose, for example, that remote "work" has had this command run in
 it. Then after pulling from "work", git-annex will know about an
 additional remote, "work-foo". That remote will be accessed using "work" as
-a proxy. (This only works for remotes accessed over ssh.)
+a proxy.
+
+Proxies can only be accessed via ssh.
 
 # OPTIONS
 
@@ -33,7 +35,7 @@ a proxy. (This only works for remotes accessed over ssh.)
 # SEE ALSO
 
 [[git-annex]](1)
-[[git-annex-cluster]](1)
+[[git-annex-updatecluster]](1)
 
 # AUTHOR
 

doc/git-annex.mdwn

@@ -326,6 +326,12 @@ content from the key-value store.
   
   See [[git-annex-required]](1) for details.
 
+* `updatecluster`
+
+  Update records with cluster configuration.
+  
+  See [[git-annex-updatecluster](1) for details.
+
 * `updateproxy`
 
   Update records with proxy configuration.
@@ -1379,8 +1385,8 @@ repository, using [[git-annex-config]]. See its man page for a list.)
 
 * `annex.cluster.<name>`
 
-  [[git-annex-cluster]] sets this to the UUID of a cluster, to 
-  enable the local repository to act as a proxy to the cluster.
+  [[git-annex-updatecluster]] sets this to the UUID of a cluster
+  based on `remote.<name>.annex-cluster-node` configuration.
 
   Note that cluster UUIDs are not the same as repository UUIDs,
   and a repository UUID cannot be used here.

git-annex.cabal

@@ -720,6 +720,7 @@ Executable git-annex
     Command.UnregisterUrl
     Command.Untrust
     Command.Unused
+    Command.UpdateCluster
     Command.UpdateProxy
     Command.Upgrade
     Command.VAdd