add timestamp to uuid.log

* New or changed repository descriptions in uuid.log now have a timestamp,
  which is used to ensure the newest description is used when the uuid.log
  has been merged.
* Note that older versions of git-annex will display the timestamp as part
  of the repository description, which is ugly but otherwise harmless.

UUID.hs

@@ -6,7 +6,9 @@
  - UUIDs of remotes are cached in git config, using keys named
  - remote.<name>.annex-uuid
  -
- - Copyright 2010 Joey Hess <joey@kitenet.net>
+ - uuid.log stores a list of known uuids, and their descriptions.
+ -
+ - Copyright 2010-2011 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -18,11 +20,11 @@ module UUID (
 	prepUUID,
 	genUUID,
 	describeUUID,
-	uuidMap,
-	uuidLog
+	uuidMap
 ) where
 
 import qualified Data.Map as M
+import Data.Time.Clock.POSIX
 
 import Common.Annex
 import qualified Git
@@ -30,13 +32,14 @@ import qualified Annex.Branch
 import Types.UUID
 import qualified Build.SysConfig as SysConfig
 import Config
+import UUIDLog
 
 configkey :: String
 configkey = "annex.uuid"
 
 {- Filename of uuid.log. -}
-uuidLog :: FilePath
-uuidLog = "uuid.log"
+logfile :: FilePath
+logfile = "uuid.log"
 
 {- Generates a UUID. There is a library for this, but it's not packaged,
  - so use the command line tool. -}
@@ -50,8 +53,7 @@ genUUID = liftIO $ pOpen ReadFromPipe command params $ \h -> hGetLine h
 			-- uuidgen generates random uuid by default
 			else []
 
-{- Looks up a repo's UUID. May return "" if none is known.
- -}
+{- Looks up a repo's UUID. May return "" if none is known. -}
 getUUID :: Git.Repo -> Annex UUID
 getUUID r = do
 	g <- gitRepo
@@ -76,26 +78,17 @@ getUncachedUUID r = Git.configGet r configkey ""
 prepUUID :: Annex ()
 prepUUID = do
 	u <- getUUID =<< gitRepo
-	when ("" == u) $ do
+	when (null u) $ do
 		uuid <- liftIO genUUID
 		setConfig configkey uuid
 
-{- Records a description for a uuid in the uuidLog. -}
+{- Records a description for a uuid in the log. -}
 describeUUID :: UUID -> String -> Annex ()
-describeUUID uuid desc = Annex.Branch.change uuidLog $
-	serialize . M.insert uuid desc . parse
-	where
-		serialize m = unlines $ map (\(u, d) -> u++" "++d) $ M.toList m
+describeUUID uuid desc = do
+	ts <- liftIO $ getPOSIXTime
+	Annex.Branch.change logfile $
+		showLog id . changeLog ts uuid desc . parseLog Just
 
-{- Read the uuidLog into a Map -}
+{- Read the uuidLog into a simple Map -}
 uuidMap :: Annex (M.Map UUID String)
-uuidMap = parse <$> Annex.Branch.get uuidLog
-
-parse :: String -> M.Map UUID String
-parse = M.fromList . map pair . lines
-	where
-		pair l
-			| null ws = ("", "")
-			| otherwise = (head ws, unwords $ drop 1 ws)
-			where
-				ws = words l
+uuidMap = (simpleMap . parseLog Just) <$> Annex.Branch.get logfile

debian/changelog

@@ -7,6 +7,11 @@ git-annex (3.20110929) UNRELEASED; urgency=low
     in addition to their descriptions.
   * Contain the zombie hordes.
   * Add locking to avoid races when changing the git-annex branch.
+  * New or changed repository descriptions in uuid.log now have a timestamp,
+    which is used to ensure the newest description is used when the uuid.log
+    has been merged.
+  * Note that older versions of git-annex will display the timestamp as part
+    of the repository description, which is ugly but otherwise harmless.
 
  -- Joey Hess <joeyh@debian.org>  Thu, 29 Sep 2011 18:58:53 -0400
 

doc/bugs/uuid.log_trust.log_and_remote.log_merge_wackiness.mdwn

@@ -21,6 +21,7 @@ would keep working, ignoring the timestamp.
 - uuid.log: "uuid description timestamp" would work; old git-annex 
   would just treat the timestamp as part of the description which would be
   ok
+  > update: converted! --[[Joey]] 
 - trust.log: "uuid trustlevel timestamp" would work; old git-annex
   ignores trailing words
 - remote.log: "uuid key=value ... timestamp" is on the edge but does work

doc/internals.mdwn

@@ -42,10 +42,10 @@ more useful than a UUID when it refers to a repository that does not have
 a configured git remote pointing at it.
 
 The file format is simply one line per repository, with the uuid followed by a
-space and then the description through to the end of the line. Example:
+space and then the description, followed by a timestamp. Example:
 
-	e605dca6-446a-11e0-8b2a-002170d25c55 laptop
-	26339d22-446b-11e0-9101-002170d25c55 usb disk
+	e605dca6-446a-11e0-8b2a-002170d25c55 laptop timestamp=1317929189.157237s
+	26339d22-446b-11e0-9101-002170d25c55 usb disk timestamp=1317929330.769997s
 
 ## `remotes.log`
 

test.hs

@@ -31,6 +31,7 @@ import qualified Types
 import qualified GitAnnex
 import qualified LocationLog
 import qualified UUID
+import qualified UUIDLog
 import qualified Trust
 import qualified Remote
 import qualified RemoteLog
@@ -78,6 +79,8 @@ quickcheck = TestLabel "quickcheck" $ TestList
 	, qctest "prop_relPathDirToFile_basics" Utility.Path.prop_relPathDirToFile_basics
 	, qctest "prop_cost_sane" Config.prop_cost_sane
 	, qctest "prop_hmacWithCipher_sane" Crypto.prop_hmacWithCipher_sane
+	, qctest "prop_TimeStamp_sane" UUIDLog.prop_TimeStamp_sane
+	, qctest "prop_addLog_sane" UUIDLog.prop_addLog_sane
 	]
 
 blackbox :: Test