[pve-devel] [PATCH http-server] http: support Content-Encoding=deflate

[Thomas Lamprecht]

Am 16/04/2024 um 13:44 schrieb Maximiliano Sandoval:
> Add support for compressing the body of responses with
> `Content-Encoding=deflate` as per [RFC9110]. Note that in this context
> `deflate` is actually a "zlib" data format as defined in [RFC1950].
> 
> [RFC9110] https://www.rfc-editor.org/rfc/rfc9110#name-deflate-coding
> [RFC1950] https://www.rfc-editor.org/rfc/rfc1950
> 
> Signed-off-by: Maximiliano Sandoval <m.sandoval at proxmox.com>
> ---
>  src/PVE/APIServer/AnyEvent.pm | 23 +++++++++++++++++------
>  1 file changed, 17 insertions(+), 6 deletions(-)
> 
> diff --git a/src/PVE/APIServer/AnyEvent.pm b/src/PVE/APIServer/AnyEvent.pm
> index b60b825..a43d6bb 100644
> --- a/src/PVE/APIServer/AnyEvent.pm
> +++ b/src/PVE/APIServer/AnyEvent.pm
> @@ -123,6 +123,7 @@ sub cleanup_reqstate {
>      delete $reqstate->{request};
>      delete $reqstate->{proto};
>      delete $reqstate->{accept_gzip};
> +    delete $reqstate->{accept_deflate};
>      delete $reqstate->{starttime};
>  
>      if ($reqstate->{tmpfilename}) {
> @@ -288,7 +289,7 @@ sub response {
>      $reqstate->{hdl}->timeout($self->{timeout});
>  
>      $nocomp = 1 if !$self->{compression};
> -    $nocomp = 1 if !$reqstate->{accept_gzip};
> +    $nocomp = 1 if !$reqstate->{accept_gzip} && !$reqstate->{accept_deflate};
>  
>      my $code = $resp->code;
>      my $msg = $resp->message || HTTP::Status::status_message($code);
> @@ -333,11 +334,17 @@ sub response {
>  	$content_length = length($content);
>  
>  	if (!$nocomp && ($content_length > 1024)) {
> -	    my $comp = Compress::Zlib::memGzip($content);
> -	    $resp->header('Content-Encoding', 'gzip');
> -	    $content = $comp;
> -	    $content_length = length($content);
> +	    if ($reqstate->{accept_gzip}) {
> +		my $comp = Compress::Zlib::memGzip($content);
> +		$resp->header('Content-Encoding', 'gzip');
> +		$content = $comp;
> +	    } elsif ($reqstate->{accept_deflate}) {
> +		my $comp = Compress::Zlib::compress($content);
> +		$resp->header('Content-Encoding', 'deflate');
> +		$content = $comp;
> +	    }
>  	}
> +	$content_length = length($content);
>  	$resp->header("Content-Length" => $content_length);
>  	$reqstate->{log}->{content_length} = $content_length;
>  
> @@ -735,7 +742,10 @@ sub proxy_request {
>  	    if $auth->{api_token};
>  	$headers->{'CSRFPreventionToken'} = $auth->{token}
>  	    if $auth->{token};
> -	$headers->{'Accept-Encoding'} = 'gzip' if ($reqstate->{accept_gzip} && $self->{compression});
> +	if ($self->{compression}) {
> +	    $headers->{'Accept-Encoding'} = 'deflate' if $reqstate->{accept_deflate};
> +	    $headers->{'Accept-Encoding'} = 'gzip' if $reqstate->{accept_gzip};

it might warrant a comment (and a hint in the commit message) that gzip is
favored, otherwise it might seem like a bug that if both, accept_deflate and
accept_gzip are set, only the gzip one is set (even though passing a list
would be supported), or was this overlooked?