git-remote-annex enableremote to support readonly webdav

* Allow enableremote of an existing webdav special remote that has
  read-only access.
* git-remote-annex: Use enableremote rather than initremote.

CHANGELOG

@@ -6,6 +6,9 @@ git-annex (10.20250103) UNRELEASED; urgency=medium
   * Avoid verification error when addurl --verifiable is used
     with an url claimed by a special remote other than the web.
   * Fix installation on Android.
+  * Allow enableremote of an existing webdav special remote that has
+    read-only access.
+  * git-remote-annex: Use enableremote rather than initremote.
 
  -- Joey Hess <id@joeyh.name>  Fri, 03 Jan 2025 14:30:38 -0400
 

CmdLine/GitRemoteAnnex.hs

@@ -586,14 +586,15 @@ withSpecialRemote cfg@(SpecialRemoteConfig {}) sab a = case specialRemoteName cf
 	Nothing -> specialRemoteFromUrl sab inittempremote
   where
 	-- Initialize a new special remote with the provided configuration
-	-- and name.
+	-- and name. This actually does a Remote.Enable, because the
+	-- special remote has already been initialized somewhere before.
 	initremote remotename = do
 		let c = M.insert SpecialRemote.nameField (Proposed remotename) $
 			M.delete (Accepted "config-uuid") $
 			specialRemoteConfig cfg
 		t <- either giveup return (SpecialRemote.findType c)
 		dummycfg <- liftIO dummyRemoteGitConfig
-		(c', u) <- Remote.setup t Remote.Init (Just (specialRemoteUUID cfg)) 
+		(c', u) <- Remote.setup t (Remote.Enable c) (Just (specialRemoteUUID cfg)) 
 			Nothing c dummycfg
 			`onException` cleanupremote remotename
 		Logs.Remote.configSet u c'

Remote/WebDAV.hs

@@ -137,7 +137,9 @@ webdavSetup ss mu mcreds c gc = do
 	(c', encsetup) <- encryptionSetup c gc
 	pc <- either giveup return . parseRemoteConfig c' =<< configParser remote c'
 	creds <- maybe (getCreds pc gc u) (return . Just) mcreds
-	testDav url creds
+	case ss of
+		Init -> testDav url creds
+		_ -> noop
 	gitConfigSpecialRemote u c' [("webdav", "true")]
 	c'' <- setRemoteCredPair ss encsetup pc gc (davCreds u) creds
 	return (c'', u)

doc/special_remotes/webdav/comment_24_6c16a7c9abb257be4d046e27e11bacdf._comment

@@ -1,10 +1,9 @@
 [[!comment format=mdwn
  username="joey"
- subject="""comment 24"""
- date="2023-06-20T17:25:27Z"
+ subject="""Re: read-only webdav access"""
+ date="2025-01-07T18:51:26Z"
  content="""
-httpalso now supports chunking. So I think there's no need to add readonly
-support to webdav, probably. But if you disagree, I do think it would be
-possible to add. Just probably not useful.. after all webdav minus writing
-is little different than http. If you disagree, open a [[todo]].
+Update: Since I posted this comment, enableremote of an existing webdav
+special remote has been made to work even if you cannot write to it. So
+there is no need to use httpalso and no need for a readonly=true.
 """]]

doc/todo/Read-only_support_for_webdav/comment_1_1fd87a5ab19a81a1b094efea7e70e581._comment

@@ -0,0 +1,25 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2025-01-07T18:51:26Z"
+ content="""
+I'm not sure I'd trust an old comment of mine to reflect whether httpalso
+supports http authentication. From what I can see, without trying it, it
+will use git-credential to prompt for password when receiving a 401
+response, the same as all other parts of git-annex that download urls
+do nowadays.
+
+Re git-remote-annex, I see your point though. Since it does set up the
+remote when cloning, and webdav remote setup calls involves creating and
+deleting a test file, the user needs write access currently. (Whether that
+test file is worth it doing at all, I'm on the fence about. It seemed like
+a good idea way back when.)
+
+I think that, rather than needing readonly=true, enableremote of a webdav
+special remote should just assume it exists and not test write access to
+it. Then it will work with readonly access. I've implemented that.
+
+And I've made git-remote-annex on git clone do an enableremote, rather than
+an initremote. That should make it work with a readonly webdav special
+remote.
+"""]]