Generating GraphQL Context

graphql-kotlin-spring-server provides a Spring specific implementation of GraphQLContextFactory and the context.

• SpringGraphQLContext - Implements the Spring ServerRequest and federation tracing HTTPRequestHeaders
• SpringGraphQLContextFactory - Generates a SpringGraphQLContext per request

If you are using graphql-kotlin-spring-server, you should extend SpringGraphQLContext and SpringGraphQLContextFactory to maintain support with all the other features.

class MyGraphQLContext(val myCustomValue: String, request: ServerRequest) : SpringGraphQLContext(request)

@Component
class MyGraphQLContextFactory : SpringGraphQLContextFactory<MyGraphQLContext>() {
    override suspend fun generateContext(request: ServerRequest): MyGraphQLContext {
        val customVal = request.headers().firstHeader("MyHeader") ?: "defaultValue"
        return MyGraphQLContext(customVal, request)
    }
}

Once your application is configured to build your custom MyGraphQLContext, you can then specify it as function argument. While executing the query, the corresponding GraphQL context will be read from the environment and automatically injected to the function input arguments. This argument will not appear in the GraphQL schema.

For more details, see the Contextual Data Documentation.

Federated Context

If you need federation tracing support, you can set the appropiate configuration properties. The provided SpringGraphQLContext implements the required federation methods for tracing, so as long as you extend this context class you will maintain feature support.