wp_die() should return proper errors when called from xmlrpc

[koke]

Right now, when something goes wrong you get a html page with the error instead of a proper xml response.

Example: try to post the same comment twice

[koke]

Added patch that fixes the issue.

I'm not really sure if the best way to proceed is adding the function in xmlrpc.php, or checking for the XMLRPC_REQUEST constant in wp-include/functions.php

[nacin]

Big plus one on your proposed solution.

[josephscott]

+1 I like it

[hakre]

Related: #9093

[ericmann]

I like your solution, and I think the location is accurate since we're hooking in to the wp_die_handler filter. The only thing I would recommend is changing the method name to xmlrpc_die_handler() for consistency (since the default is _default_wp_die_handler). I'd hate for some unsuspecting developer to call xmlrpc_wp_die() directly rather than wp_die().

Attaching a slightly modified patch that changes the method name and uses a simpler filter return.

[westi]

Replying to ericmann:

I like your solution, and I think the location is accurate since we're hooking in to the wp_die_handler filter. The only thing I would recommend is changing the method name to xmlrpc_die_handler() for consistency (since the default is _default_wp_die_handler). I'd hate for some unsuspecting developer to call xmlrpc_wp_die() directly rather than wp_die().

Attaching a slightly modified patch that changes the method name and uses a simpler filter return.

A better name for the function is a good idea.

Using a closure instead of a function to hook this in isn't as it makes it really hard to remove_filter the function.

Also I think we shouldn't define the function in xmlrpc.php - someone might want to re-use it when serving xmlrpc requests on a different endpoint.

[westi]

[17643]

Introduce a special wp_die handler for XMLRPC requests to ensure we send an XML response.
Props koke for the original patch. See #16748.

[westi]

@koke: Please could run some testing of this with the clients and know failure cases and then feedback if all is ok.

[ericmann]

Replying to westi:

Using a closure instead of a function to hook this in isn't as it makes it really hard to remove_filter the function.

I can accept that. And I like the actual commit patch even better.

Also I think we shouldn't define the function in xmlrpc.php - someone might want to re-use it when serving xmlrpc requests on a different endpoint.

I think defining a different XMLRPC endpoint would be an extreme edge case, and since the custom function was specific to our XMLRPC handler I figured that would be the best place to put it. But thinking forward to the possibility of other custom die() handlers (I've seen a couple of custom REST systems in development) I think dropping it in functions is a better solution.

[koke]

Works for me (tested in trunk)