Mock resolvers
For testing scenarios, you can configure a mock resolver in a GraphQLResolverMap Gloo custom resource. Mock resolvers do not require resolver servers to exist, and instead can immediately return a mocked response. Then, map fields from your schema definition to resolvers in a GraphQLSchema CR.
Step 1: Mock resolvers
Define your mock resolvers in a GraphQLResolverMap CR. Note that you can specify only one of asyncResponse, errorResponse, or syncResponse.
apiVersion: apimanagement.gloo.solo.io/v2
kind: GraphQLResolverMap
metadata:
name:
namespace:
spec:
# Resolver map
types:
Query:
fields:
# Replace 'nameOfField' with the name of the field that you
# previously defined for this query
<nameOfField>:
# Configuration for generating outgoing requests to a gRPC API
resolvers:
# You can specify only one type of mock resolver: asyncResponse, errorResponse, or syncResponse
mockResolver:
# The JSON object response to immediately return to the GraphQL
# execution engine. Can be templated using variables from the # variables field
asyncResponse:
# An error response to return for this field
errorResponse:
# The JSON object response to immediately return to the GraphQL
# execution engine. Can be templated using variables from the # variables field
syncResponse:
In this example resolver map, a mock resolver is defined for the productsForHome field of the top-level query type. Two JSON objects in the syncResponse are defined in order to send example responses to test queries.
apiVersion: apimanagement.gloo.solo.io/v2
kind: GraphQLResolverMap
metadata:
name: bookinfo-mock-resolvermap
namespace: bookinfo
spec:
types:
Query:
fields:
productsForHome:
resolvers:
mockResolver:
syncResponse:
# To be properly converted from YAML to JSON, the entry content
# must be on a separate line after the hyphen (-).
-
id: 1
author: Bill
title: My Life
descriptionHtml: a book description
pages: 100
year: 1998
reviews:
-
reviewer: Sam
text: "The best!"
-
id: 2
author: George
title: Bill's Life
descriptionHtml: the real story of Bill's life
pages: 200
year: 1999
reviews:
-
reviewer: Bill
text: "Meh ... read my book instead"
Step 2: Map schema to resolvers
Map the types and fields from your schema definition (ApiDoc) to the resolver servers (GraphQLResolverMap) in a GraphQLSchema Gloo CR. The GraphQLSchema CR ensures that the GraphQL resolver services can access the field information for each type.
apiVersion: apimanagement.gloo.solo.io/v2
kind: GraphQLSchema
metadata:
name:
namespace:
spec:
# Allow GraphQL servers that you define in GraphQLResolverMap CRs to resolve queries locally
resolved:
# Additional options on the schema
options:
# Enable introspection for the schema. Defaults to false.
enableIntrospection:
# Limit the maximum nesting on a query that runs against this schema.
# Any GraphQL operation that queries past the max depth adds an error message to the response and returns as null.
# If not configured, or the value is 0, the query depth is unbounded.
maxDepth:
# References to GraphQLResolverMap resources for resolvers.
# Resolver maps that are higher in this list have a higher priority
# over lower items when tie-breaking field resolver configurations exist.
resolverMapRefs:
- clusterName:
name:
namespace:
# Reference to ApiDoc resource for schema definitions
schemaRef:
clusterName:
name:
namespace:
In this example GraphQLSchema resource, the resolvers from bookinfo-mock-resolvermap are mapped to the schema definition from bookinfo-rest-apidoc.
apiVersion: apimanagement.gloo.solo.io/v2
kind: GraphQLSchema
metadata:
name: bookinfo-mock-graphqlschema
namespace: bookinfo
spec:
resolved:
options: {}
resolverMapRefs:
- clusterName: $CLUSTER_NAME
name: bookinfo-mock-resolvermap
namespace: bookinfo
schemaRef:
clusterName: $CLUSTER_NAME
name: bookinfo-rest-apidoc
namespace: bookinfo
Reference
For more information, see the Gloo Gateway API reference for the GraphQLResolverMap CR and GraphQLSchema CR.