Dev
GraphQL Resolver Mock Generator
Before a database schema is finalized, frontend teams need runnable GraphQL resolvers to develop against. Returning undefined from a stub is fragile. A mock resolver generator produces properly structured functions with the correct three-argument signature, a realistic return shape, and hardcoded values simulating a real data source. Three style options control the async pattern. Async/await is the right default for modern Node.js and easiest to refactor into real database calls. Promise style returns Promise.resolve() explicitly, useful for libraries expecting thenables. Sync style returns data directly — only appropriate for computed fields or pure mocks. Each resolver returns id, name, and createdAt. Set count from 1 to 20. Output drops into Apollo Server, GraphQL Yoga, and Mercurius resolver maps. Replace hardcoded values with real data-fetching logic when the database is ready.
How to use
- Choose your options above
- Click Generate
- Copy your result
Detailed instructions
- Set the count field to match the number of Query or Mutation fields you need to stub out.
- Select a style — async/await for modern codebases, Promise for callback-heavy code, or sync for computed-only fields.
- Click Generate to produce the resolver functions with entity names, arguments, and return objects.
- Copy individual resolvers or the full list, then paste them into your resolvers map or test file.
- Replace the hardcoded return values with your actual data-fetching logic when you're ready to connect a real source.
Use Cases
- •Unblocking Apollo Client feature work while the database schema is still being designed
- •Seeding a local GraphQL Yoga server for a client walkthrough or clickable prototype demo
- •Wiring generated stubs directly into Jest or Vitest as baseline happy-path resolver tests
- •Populating graphql-tools addMocksToSchema or MSW handlers with consistent return shapes
- •Teaching the four-argument resolver signature live in a workshop or onboarding session
Tips
- →Generate with async/await style first — it's easiest to search-replace the return value with a real database call later.
- →Pair the output with graphql-tools' addMocksToSchema to get instant mock responses across your entire schema without wiring each resolver manually.
- →Use the generated timestamp field as a sort key in your UI to verify that ordering logic works before real data arrives.
- →When writing unit tests, copy one resolver per test file and override only the return value — avoid sharing a single mock across multiple test suites to prevent state bleed.
- →If you're teaching GraphQL, generate the sync style first so learners see the simplest form, then show async/await as the real-world upgrade.
- →Match your generation count to a single feature slice (e.g., all User resolvers) rather than the whole schema at once — smaller batches are easier to review and integrate.
FAQ
what's the difference between async/await, Promise, and sync resolver styles
Async/await uses the async keyword and is the right default for most modern Node.js projects — it reads cleanly and handles errors naturally with try/catch. Promise style returns an explicit Promise.resolve(), useful when integrating with older callback-based libraries. Sync style returns data directly and is only appropriate for computed fields or pure mock stubs that will never do I/O.
can I paste these resolver stubs straight into Apollo Server without changes
Yes — the output uses the standard (_parent, args, context) signature that Apollo Server, GraphQL Yoga, Mercurius, and the reference graphql-js library all expect. If you're using a schema-builder like Pothos or Nexus, you may need to adjust the signature slightly to match that builder's resolver API.
how do I turn these mock resolvers into unit tests quickly
Copy a generated resolver into your Jest or Vitest test file and call it directly with a fake args object and a mock context. Every stub returns a consistent shape — id (UUID), name, and createdAt — so your happy-path assertion is already set up. To cover error cases, wrap the resolver in jest.fn() and override the return value or throw.
what fields does each generated resolver return
Every resolver returns an object with three fields: id (a UUID v4 string), name (an entity-type-prefixed string with a random number, like user_3847), and createdAt (an ISO 8601 timestamp from a random point in the past). If your schema requires additional fields, add them manually after pasting the stub.
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