Startup Scanning

GraQL does add slight overhead to the startup of your micronaut application. At startup, it:

1. Uses the underlying micronaut application context to inspect any registered beans of stereotypes GraQLComponent and GraQLScalar.
2. Creates delegates for data fetches (queries, mutations, fetches), data loaders, and exception handlers.
3. Registers scalars.
4. Uses GraQLFactory to create the underlying graphql.GraphQL for micronaut GraphQL integration.

GraQLComponent Registration

Delegates

Delegates form the core of GraQL.

During the scanning phase, annotations like @GraQLQuery are used to create delegate instances that receive input from GraphQL and invoke methods on your @GraQLComponents.

A central (and replaceable/extensible!) GraQLDelegateFactory interface is responsible for stating which annotations are recognized and providing a GraQLDelegationConfigurator implementation for each annotation.

This allows you to extend GraQL with new delegates, annotations, and your own implementation of delegation behavior.

Exception Handlers

Components annotated with GraQLExceptionHandler are registered and provided to the GraQLGlobalExceptionHandler.

If a GraphQL operation throws an exception, the global exception handler checks for an appropriate delegate.

If one exists for the exception type, it's then invoked.

GraQLScalar Registration

GraQLScalar scanning simply confirms that annotated components implement the correct interface (graphql.schema.Coercing). Once validated, they're available to the internal GraQLFactory for configuration.