Resolvers

A schema can promise that a book has a title and credited authors, but it does not explain where those values come from. The title might already be in a catalog record, while the authors require another lookup. Someone must connect each requested field to the appropriate data or action.

Resolvers provide that connection.

This chapter follows a bookstore query through execution, explains the information available to a resolver, and shows how to keep data access, business rules, and GraphQL response behavior working together.