diff mbox series

[v2,1/2] transport: warn if server options are unsupported

Message ID af3cc05324f53316eedb2f437789eacb24c11489.1554841624.git.jonathantanmy@google.com (mailing list archive)
State New, archived
Headers show
Series Server options when cloning | expand

Commit Message

Jonathan Tan April 9, 2019, 8:31 p.m. UTC
Server options were added in commit 5e3548ef16 ("fetch: send server
options when using protocol v2", 2018-04-24), supported only for
protocol version 2. Add a warning if server options are specified for
the user if a legacy protocol is used instead.

An effort is made to avoid printing the same warning more than once by
clearing transport->server_options after the warning, but this does not
fully avoid double-printing (for example, when backfulling tags using
another fetch with a non-reusable transport).

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
---
 t/t5702-protocol-v2.sh | 17 +++++++++++++++++
 transport.c            |  8 ++++++++
 2 files changed, 25 insertions(+)

Comments

Jonathan Nieder April 9, 2019, 8:45 p.m. UTC | #1
Hi,

Jonathan Tan wrote:

> Server options were added in commit 5e3548ef16 ("fetch: send server
> options when using protocol v2", 2018-04-24), supported only for
> protocol version 2. Add a warning if server options are specified for
> the user if a legacy protocol is used instead.
>
> An effort is made to avoid printing the same warning more than once by
> clearing transport->server_options after the warning, but this does not
> fully avoid double-printing (for example, when backfulling tags using
> another fetch with a non-reusable transport).
>
> Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
> ---
>  t/t5702-protocol-v2.sh | 17 +++++++++++++++++
>  transport.c            |  8 ++++++++
>  2 files changed, 25 insertions(+)

Thanks for writing this.  I'd be in favor of making this die().
Compare what we already do in push:

	if (args->push_options && !push_options_supported)
		die(_("the receiving end does not support push options"));

What happens in the case of push with protocol v0, where server options
are supported?

[...]
> --- a/transport.c
> +++ b/transport.c
> @@ -252,6 +252,12 @@ static int connect_setup(struct transport *transport, int for_push)
>  	return 0;
>  }
>  
> +static void warn_server_options_unsupported(struct transport *transport)
> +{
> +	warning(_("Ignoring server options because protocol version does not support it"));

nits:
- error and warning messages tend to use lowercase
- the user running into this may want to know how to switch to a better
  protocol version.  Is there e.g. a manpage we can point them to?

For example:

	fatal: server options require protocol version 2 or later
	hint: see protocol.version in "git help config" for more details

> +	transport->server_options = NULL;

Should this use a static to also warn only once in the tag-catchup case
you mentioned?

> +}
> +
>  /*
>   * Obtains the protocol version from the transport and writes it to
>   * transport->data->version, first connecting if not already connected.
> @@ -286,6 +292,7 @@ static struct ref *handshake(struct transport *transport, int for_push,
>  		break;
>  	case protocol_v1:
>  	case protocol_v0:
> +		warn_server_options_unsupported(transport);
>  		get_remote_heads(&reader, &refs,
>  				 for_push ? REF_NORMAL : 0,
>  				 &data->extra_have,
> @@ -363,6 +370,7 @@ static int fetch_refs_via_pack(struct transport *transport,
>  		break;
>  	case protocol_v1:
>  	case protocol_v0:
> +		warn_server_options_unsupported(transport);
>  		refs = fetch_pack(&args, data->fd, data->conn,

Looks like this only affects fetch, so the question above about push
is only about the commit message.

With whatever subset of the suggested changes makes sense,
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>

Thanks.
Junio C Hamano April 10, 2019, 3:51 a.m. UTC | #2
Jonathan Nieder <jrnieder@gmail.com> writes:

> Thanks for writing this.  I'd be in favor of making this die().
> Compare what we already do in push:
>
> 	if (args->push_options && !push_options_supported)
> 		die(_("the receiving end does not support push options"));

That's a good point.

> What happens in the case of push with protocol v0, where server options
> are supported?

Are, or are not?

In any case, all other suggestions in your reviews are worth
following up, I would think.  Thanks for a quick review.
diff mbox series

Patch

diff --git a/t/t5702-protocol-v2.sh b/t/t5702-protocol-v2.sh
index db4ae09f2f..f1a3ff1021 100755
--- a/t/t5702-protocol-v2.sh
+++ b/t/t5702-protocol-v2.sh
@@ -182,6 +182,12 @@  test_expect_success 'server-options are sent when using ls-remote' '
 	grep "server-option=world" log
 '
 
+test_expect_success 'warn if using server-option with ls-remote with legacy protocol' '
+	GIT_TEST_PROTOCOL_VERSION=0 git -c protocol.version=0 \
+		ls-remote -o hello -o world "file://$(pwd)/file_parent" master 2>err &&
+
+	grep "Ignoring server options" err
+'
 
 test_expect_success 'clone with file:// using protocol v2' '
 	test_when_finished "rm -f log" &&
@@ -251,6 +257,17 @@  test_expect_success 'server-options are sent when fetching' '
 	grep "server-option=world" log
 '
 
+test_expect_success 'warn if using server-option with fetch with legacy protocol' '
+	test_when_finished "rm -rf temp_child" &&
+
+	git init temp_child &&
+
+	GIT_TEST_PROTOCOL_VERSION=0 git -C temp_child -c protocol.version=0 \
+		fetch -o hello -o world "file://$(pwd)/file_parent" master 2>err &&
+
+	grep "Ignoring server options" err
+'
+
 test_expect_success 'upload-pack respects config using protocol v2' '
 	git init server &&
 	write_script server/.git/hook <<-\EOF &&
diff --git a/transport.c b/transport.c
index e078812897..14f14ef93c 100644
--- a/transport.c
+++ b/transport.c
@@ -252,6 +252,12 @@  static int connect_setup(struct transport *transport, int for_push)
 	return 0;
 }
 
+static void warn_server_options_unsupported(struct transport *transport)
+{
+	warning(_("Ignoring server options because protocol version does not support it"));
+	transport->server_options = NULL;
+}
+
 /*
  * Obtains the protocol version from the transport and writes it to
  * transport->data->version, first connecting if not already connected.
@@ -286,6 +292,7 @@  static struct ref *handshake(struct transport *transport, int for_push,
 		break;
 	case protocol_v1:
 	case protocol_v0:
+		warn_server_options_unsupported(transport);
 		get_remote_heads(&reader, &refs,
 				 for_push ? REF_NORMAL : 0,
 				 &data->extra_have,
@@ -363,6 +370,7 @@  static int fetch_refs_via_pack(struct transport *transport,
 		break;
 	case protocol_v1:
 	case protocol_v0:
+		warn_server_options_unsupported(transport);
 		refs = fetch_pack(&args, data->fd, data->conn,
 				  refs_tmp ? refs_tmp : transport->remote_refs,
 				  dest, to_fetch, nr_heads, &data->shallow,