Subgraph Mock
A minimal, configurable subgraph mock. See example-config.yaml for documentation of the available
configuration options.
Example usage
Limitations
This is a minimal mock server designed for use in testing/development scenarios where a real GraphQL server is needed to respond to queries. It is not a fully spec-compliant GraphQL server.
It does not support:
- subscriptions
- mutations
- mixed queries with both introspection and concrete fields
Features
This mock server is mainly designed to act as multiple subgraphs behind a federated supergraph. It will respond to correct queries with randomly generated data as specified by the configuration provided. Invalid queries will be rejected with their validation errors included in the response.
Introspection-only queries will be responded to with correct data, not random data. Mixed queries with both introspection and concrete data will be populated entirely with random data.
Federation
This mock server has partial Federation v2 support. It can understand and parse subgraph schemas
that use the built-in Federation v2 directives. It does not currently do any actual resolution of
the @link directive, so any imports or renames as specified in that directive will not work.
Subgraph Overrides
If your test scenario calls for behavioral differences between subgraphs, the mock server will
respond using those subgraphs' specific configurations to requests made at /<subgraph name>
instead of at /. See example-config.yaml for details on how to specify these overrides.
If the server is started with a federated supergraph schema, it will not infer subgraph-specific schemas for any requests to the subgraph-overridden endpoints. The subgraph endpoints only inherit behavioral differences, and still operate under the full provided schema for all validation and introspection purposes.
Non-federated Usage
This mock server can also be used as a standalone GraphQL mock server without any federation behavior. Just provide a standard schema file and configuration without subgraph overrides and it will respond to valid queries for that schema.