How to Resolvers Work?
- A client makes a GraphQL query request and sends it to the GraphQL server. Each field in the query corresponds to a separate resolver function defined in the GraphQL server.
- The resolvers are responsible for fetching the data, from the database or some other services, for all the fields that are requested in the query.
- Once the data is retrieved, the resolver sends back the response in the same format as requested by the client
- A resolver accepts 4 arguments:
- Parent: It represents the data that is returned by the parent’s resolver field, if we have nested resolvers present inside the query.
- Arguments: These represent the additional arguments that is passed to the query by the user.
- Context: It represents a shared object that is present across the resolvers that get called during a single query operation.
- Info: It represents the data that is present during the query operation, and represents the state of the query, like the field or the path to the field for which the resolver is getting resolved.
Resolvers in GraphQL
Resolvers are a crucial part of GraphQL that determines how data is fetched and returned in response to a query. They act as the bridge between the client’s request and the data source, whether it’s a database, API, or any other data store. Resolvers are responsible for fetching the data for each field in a query and transforming it into the format expected by the client. In this article, we will learn about Resolvers along with an understanding of How Resolvers Work with examples and so on.