Debugging GraphQL queries

This topic provides recommendations on how to debug GraphQL requests.

Debugging with PHPStorm and Xdebug

When using GraphiQL or any other client for testing GraphQL queries, you might need to debug the request processing. You can use Xdebug for debugging the PHP execution of a GraphQL query just as you would for other HTTP requests. To start debugging, add the ?XDEBUG_SESSION_START=PHPSTORM parameter to the endpoint URL. The following example shows how to establish a connection between Xdebug and PHPStorm IDE.

http://<magento2-3-server>/graphql?XDEBUG_SESSION_START=PHPSTORM

You can also enable an Xdebug connection for a particular request by setting the corresponding header parameter.

Cookie: XDEBUG_SESSION=PHPSTORM

As a result, Xdebug within the PHP execution attempts to make a connection to an IDE. If the IDE is listening, it will give the instructions to Xdebug about breakpoints and other relevant information.