Debugging Wordpress GraphiQL

Question

I'm using Wordpress with the WPGraphQL plugin.

I'm using a custom wordppress plugin that breaks WPGraphiQL, so that it hangs and the following error appears in the browser console when I navigate to "wp/wp-admin/admin.php?page=graphiql-ide":

app.js?ver=b46a34de121156c88432:30 Uncaught (in promise) Error: Internal server error
    at new t (app.js?ver=b46a34de121156c88432:30:39347)
    at app.js?ver=b46a34de121156c88432:30:78333
    at n (app.js?ver=b46a34de121156c88432:30:32923)
    at app.js?ver=b46a34de121156c88432:30:32848
    at new Promise (<anonymous>)
    at Object.then (app.js?ver=b46a34de121156c88432:30:32814)
    at Object.next (app.js?ver=b46a34de121156c88432:30:32933)
    at rh (app.js?ver=b46a34de121156c88432:30:7097)
    at ih (app.js?ver=b46a34de121156c88432:30:7610)
    at t.next (app.js?ver=b46a34de121156c88432:30:8150)

I've got as many of the Wordpress and GraphQL debugging settings turned on as I can think of, as shown below:

Config::define('SAVEQUERIES', true);
Config::define('WP_DEBUG', true);
Config::define('WP_DEBUG_DISPLAY', true);
Config::define('WP_DISABLE_FATAL_ERROR_HANDLER', true);
Config::define('SCRIPT_DEBUG', true);
Config::define('GRAPHQL_DEBUG', true);
Config::define('WP_DEBUG_LOG', true);
ini_set('display_errors', 1);

However, no error message is displayed in the wordpress debug.log file, or on any output from any of the other processes on the server.

Is there any way that I can get more debugging information out of GraphiQL, other then the "Internal server error", so that I can work out what the plugin is doing to break things?

Answer 1

This turned out to be a bug in the Wordpress GraphiQL implementation. I've submitted a pull request that's been accepted, so hopefully this won't be an issue for anyone else.