Re: [PATCH/RFC 5/6] fetch: pass refspec to http server

From: Eric Sunshine <sunshine@sunshineco.com>
Date: Apr 17, 2016, 02:33 UTC
Message-ID: <CAPig+cSxkuWB5qqVY3-m9ESmmHMKwXM+qtbRsZ1j1osjp2i3HQ@mail.gmail.com>
In-Reply-To: <1460747949-3514-6-git-send-email-dturner@twopensource.com>

On Fri, Apr 15, 2016 at 3:19 PM, David Turner <dturner@twopensource.com> wrote:

Show 21 quoted lines

> When fetching over http, send the requested refspec to the server.
> The server will then only send refs matching that refspec.  It is
> permitted for old servers to ignore that parameter, and the client
> will automatically handle this.
>
> When the server has many refs, and the client only wants a few, this
> can save bandwidth and reduce fetch latency.
>
> Signed-off-by: David Turner <dturner@twopensource.com>
> ---
> diff --git a/builtin/fetch.c b/builtin/fetch.c
> @@ -302,9 +302,27 @@ static struct ref *get_ref_map(struct transport *transport,
> -       remote_refs = transport_get_remote_refs(transport, NULL, 0);
> +       qualified_refspecs = xcalloc(refspec_count, sizeof(*qualified_refspecs));
> +       for (i = 0; i < refspec_count; i++) {
> +               if (starts_with(refspecs[i].src, "refs/")) {
> +                       qualified_refspecs[i].src = xstrdup(refspecs[i].src);
> +               } else {
> +                       struct strbuf buf = STRBUF_INIT;
> +                       strbuf_addf(&buf, "refs/heads/%s", refspecs[i].src);
> +                       qualified_refspecs[i].src = strbuf_detach(&buf, NULL);

Alternately, replace these three lines with:

    qualified_refspecs[i].src = xstrfmt("refs/heads/%s", refspecs[i].src);

and drop the braces.

Show 18 quoted lines

> +               }
> +       }
> +
> +       remote_refs = transport_get_remote_refs(transport, qualified_refspecs,
> +                                               refspec_count);
> +
> +       for (i = 0; i < refspec_count; i++) {
> +               free(qualified_refspecs[i].src);
> +       }
> +       free(qualified_refspecs);
> diff --git a/t/t5552-http-fetch-branch.sh b/t/t5552-http-fetch-branch.sh
> @@ -0,0 +1,42 @@
> +test_expect_success 'make some more commits' '
> +       (
> +               cd "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" &&
> +               test_commit 2 &&
> +               git checkout -b another_branch &&
> +               test_commit 3

Broken &&-chain.

Show 13 quoted lines

> +               git checkout -b a_third_branch &&
> +               test_commit 4
> +       )
> +'
> +
> +test_expect_success 'fetch with refspec only fetches requested branch' '
> +       test_when_finished "rm trace" &&
> +       (
> +               cd clone &&
> +               GIT_TRACE_PACKET="$TRASH_DIRECTORY/trace" git fetch origin another_branch &&
> +               ! grep "refs/heads/master" ../trace
> +       )
> +'

This could be done without the subshell, perhaps?

    GIT_TRACE_PACKET=blah git -C clone fetch ...