GraphQL Execute

The GraphQL Execute policy executes a GraphQL query by using sub-queries. The policy splits up the original GraphQL query into different sub-queries that can then be processed in different ways. The GraphQL Execute policy supports the following four different sub-queries as targets:

1. root; contains the core GraphQL query that you want to invoke on the backend.
2. __introspection; contains the introspection query that can be processed locally on the DataPower API Gateway without having to invoke the backend.
3. __rateLimit; contains the __rateLimit query that specifies the different rate limit data that you want to receive.
4. __cost; contains the __cost query that specifies the different cost data that you want to receive. This query must be in the format that is specified in the IBM GraphQL Cost Directives specification, see Introspection of Cost Analysis Results: __cost.

The root, __rateLimit, and __introspection targets can be executed in any order, or at the same time. The __cost target can be executed at any time if no response data is expected. If response data is expected, then the __cost target is executed after the root target in order to accurately return correct response cost data. After all the targets are executed, the GraphQL Execute policy combines all of the responses together. To enable the responses of the individual targets to be correctly merged with each other into a final, single response, the GraphQL Execute policy must include all of the introspection types that are associated with each level of the response data.