Subject: Re: [PATCH] http-backend: give a hint that web browser access is not supported

From: Junio C Hamano <[email-masked]>
Date: Sun, 05 Dec 2021 15:07:19 -0800

Junio C Hamano <[email-masked]> writes:

> Jan Engelhardt <[email-masked]> writes:
>
>>>Also, will the real Git clients, which are the primary intended
>>>audiences this program is trying to talk to, be OK if we suddenly
>>>start giving a non-empty 404 page?
>>
>> I am confident enough to say yes. It's not like git-http-backend
>> returned anything previously in the 404 case (like JSON or so),
>> therefore clients could not possibly depend on content.
>>
>>>If any implementations of Git HTTP client this program is serving
>>>(1) uses a 404 response as a cue to decide its next request
>>>(e.g. there may be some "try this URL and if it fails, do another
>>>one" fallback logic)
>>
>> Not sure if they heed Location: headers, but I am not changing
>> that :-)
>
> I was more worried about clients barfing because they depend on
> *not* having content.  They parse the status (404) out, and then
> leave the message part untouched---they may not even read the
> message in full, and that did not matter because there wasn't
> anything to read and discard.  Now we are sending more.
>
> As long as the leftover bytes would not cause problem with the
> action they take after that step, we would be OK.

In any case, the patch in question seems to fail t5561.

$ cd t && sh t5561-http-backend.sh -i -v
Initialized empty Git repository in /home/jch/git/t/trash directory.t5561-http-backend/.git/
checking prerequisite: NOT_ROOT

...
ok 13 - http.receivepack false

expecting success of 5561.14 'server request log matches test results': 
	check_access_log exp

--- exp.sorted	2021-12-05 23:05:09.418684299 +0000
+++ access.log.sorted	2021-12-05 23:05:09.422684296 +0000
@@ -1,33 +1,33 @@
 GET  /smart/repo.git/HEAD HTTP/1.1 200
 GET  /smart/repo.git/HEAD HTTP/1.1 200
-GET  /smart/repo.git/HEAD HTTP/1.1 403
+GET  /smart/repo.git/HEAD HTTP/1.1 403 -
 GET  /smart/repo.git/info/refs HTTP/1.1 200
 GET  /smart/repo.git/info/refs HTTP/1.1 200
-GET  /smart/repo.git/info/refs HTTP/1.1 403
+GET  /smart/repo.git/info/refs HTTP/1.1 403 -
 GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 200
-GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403
-GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403
+GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403 -
+GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403 -
 GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200
 GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200
-GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 403
+GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 403 -
 GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 200
 GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 200
-GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 403
+GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 403 -
 GET  /smart/repo.git/objects/info/alternates HTTP/1.1 200 -
 GET  /smart/repo.git/objects/info/alternates HTTP/1.1 200 -
-GET  /smart/repo.git/objects/info/alternates HTTP/1.1 403
+GET  /smart/repo.git/objects/info/alternates HTTP/1.1 403 -
 GET  /smart/repo.git/objects/info/http-alternates HTTP/1.1 200 -
 GET  /smart/repo.git/objects/info/http-alternates HTTP/1.1 200 -
-GET  /smart/repo.git/objects/info/http-alternates HTTP/1.1 403
+GET  /smart/repo.git/objects/info/http-alternates HTTP/1.1 403 -
 GET  /smart/repo.git/objects/info/packs HTTP/1.1 200
 GET  /smart/repo.git/objects/info/packs HTTP/1.1 200
-GET  /smart/repo.git/objects/info/packs HTTP/1.1 403
+GET  /smart/repo.git/objects/info/packs HTTP/1.1 403 -
 GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 200
 GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 200
-GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 403
+GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 403 -
 GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 200
 GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 200
-GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 403
+GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 403 -
 GET  /smart/repo.git/refs/heads/main HTTP/1.1 404
 GET  /smart_noexport/repo.git/HEAD HTTP/1.1 200
 GET  /smart_noexport/repo.git/HEAD HTTP/1.1 404
@@ -46,8 +46,8 @@
 GET  /smart_noexport/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 200
 GET  /smart_noexport/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 404
 POST /smart/repo.git/git-receive-pack HTTP/1.1 200 -
-POST /smart/repo.git/git-receive-pack HTTP/1.1 403
-POST /smart/repo.git/git-receive-pack HTTP/1.1 403
+POST /smart/repo.git/git-receive-pack HTTP/1.1 403 -
+POST /smart/repo.git/git-receive-pack HTTP/1.1 403 -
 POST /smart/repo.git/git-upload-pack HTTP/1.1 200 -
 POST /smart/repo.git/git-upload-pack HTTP/1.1 200 -
-POST /smart/repo.git/git-upload-pack HTTP/1.1 403
+POST /smart/repo.git/git-upload-pack HTTP/1.1 403 -
--- exp	2021-12-05 23:05:09.410684305 +0000
+++ access.log.stripped	2021-12-05 23:05:09.422684296 +0000
@@ -31,23 +31,23 @@
 GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 200
 GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 200
 GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 200
-GET  /smart/repo.git/HEAD HTTP/1.1 403
-GET  /smart/repo.git/info/refs HTTP/1.1 403
-GET  /smart/repo.git/objects/info/packs HTTP/1.1 403
-GET  /smart/repo.git/objects/info/alternates HTTP/1.1 403
-GET  /smart/repo.git/objects/info/http-alternates HTTP/1.1 403
-GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 403
-GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 403
-GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 403
+GET  /smart/repo.git/HEAD HTTP/1.1 403 -
+GET  /smart/repo.git/info/refs HTTP/1.1 403 -
+GET  /smart/repo.git/objects/info/packs HTTP/1.1 403 -
+GET  /smart/repo.git/objects/info/alternates HTTP/1.1 403 -
+GET  /smart/repo.git/objects/info/http-alternates HTTP/1.1 403 -
+GET  /smart/repo.git/objects/01/494420155a3f7587b6c26d06a55b1a8bbef2f4 HTTP/1.1 403 -
+GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.pack HTTP/1.1 403 -
+GET  /smart/repo.git/objects/pack/pack-977dd2d10981235a806ccc52cc769a44e75c889e.idx HTTP/1.1 403 -
 GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200
 POST /smart/repo.git/git-upload-pack HTTP/1.1 200 -
 GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200
 POST /smart/repo.git/git-upload-pack HTTP/1.1 200 -
-GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 403
-POST /smart/repo.git/git-upload-pack HTTP/1.1 403
-GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403
-POST /smart/repo.git/git-receive-pack HTTP/1.1 403
+GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 403 -
+POST /smart/repo.git/git-upload-pack HTTP/1.1 403 -
+GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403 -
+POST /smart/repo.git/git-receive-pack HTTP/1.1 403 -
 GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 200
 POST /smart/repo.git/git-receive-pack HTTP/1.1 200 -
-GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403
-POST /smart/repo.git/git-receive-pack HTTP/1.1 403
+GET  /smart/repo.git/info/refs?service=git-receive-pack HTTP/1.1 403 -
+POST /smart/repo.git/git-receive-pack HTTP/1.1 403 -
not ok 14 - server request log matches test results
#	
#		check_access_log exp
#