[pve-devel] applied: [PATCH http-server] fix generating 'extjs' response with exceptions/blessed errors

[Fabian Grünbichler]

On January 7, 2025 3:35 pm, Dominik Csapak wrote:
> when an api call with the 'extjs' formatter fails, the intention is that
> the api call succeeds but contains the error in the inner structure
> ('error'/'status' property). When the api call fails with a raised
> exception (e.g. PVE::APIClient::Exception), the '$res->{message}' field
> is an object instead of a string.
> 
> Currently we directly assign the message to the resulting struct, which
> we then try to convert to json. Since the message was an object,
> `to_json` fails with 'encountered object` and the whole api call returns
> a 501 error (since `handle_api2_request` returns that by default if
> anything dies there, which is IMHO not correct but a different issue.)
> 
> By 'stringifying' the message, we avoid the error in `to_json` and the
> api call can succeed.
> 
> partially fixes #6051: It improves the error message in PDM when trying
> to remote migrate and the source cannot correctly resolve the target
> remote. (We use PVE::APIClient there to query the remote).
> 
> Signed-off-by: Dominik Csapak <d.csapak at proxmox.com>
> ---
> We could of course improve the situation in other ways (too):
> * handle errors of formatters better
> * passing through exceptions in AnyEvent (seems weird a bit)
> * passing thgough the error of the 501 in the PDM ui
>   (this contains the underlying error too by accident, since `to_json`
>   writes it out)
> 
> but i opted for this for now, since this is wrong either way (as in, it cannot
> work as intended when we don't stringify the message) and improves the
> error message on PDM side (still not optimal, but at least contains the
> root cause of the error now).
> 
>  src/PVE/APIServer/Formatter/Standard.pm | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/src/PVE/APIServer/Formatter/Standard.pm b/src/PVE/APIServer/Formatter/Standard.pm
> index c4def16..5211473 100644
> --- a/src/PVE/APIServer/Formatter/Standard.pm
> +++ b/src/PVE/APIServer/Formatter/Standard.pm
> @@ -27,7 +27,7 @@ sub prepare_response_data {
>  	# HACK: extjs wants 'success' property instead of useful HTTP status codes
>  	if (HTTP::Status::is_error($res->{status})) {
>  	    $success = 0;
> -	    $new->{message} = $res->{message} || status_message($res->{status});
> +	    $new->{message} = "$res->{message}" || status_message($res->{status});
>  	    $new->{status} = $res->{status} || 200;
>  	    $res->{message} = undef;
>  	    $res->{status} = 200;
> -- 
> 2.39.5
> 
> 
> 
> _______________________________________________
> pve-devel mailing list
> pve-devel at lists.proxmox.com
> https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
> 
> 
>