@graphql-tools/mock

Mocking a GraphQL Schema

This feature allows you to add mocks to an existing GraphQL schema. The code sample demonstrates how to create a simple schema, add mocks to it, and execute a query against the mocked schema.

const { makeExecutableSchema } = require('@graphql-tools/schema');
const { addMocksToSchema } = require('@graphql-tools/mock');
const { graphql } = require('graphql');

const typeDefs = `
  type Query {
    hello: String
  }
`;

const schema = makeExecutableSchema({ typeDefs });
const schemaWithMocks = addMocksToSchema({ schema });

const query = `
  query {
    hello
  }
`;

graphql(schemaWithMocks, query).then((result) =>
  console.log(result)
);

Customizing Mock Resolvers

This feature allows you to customize the mock resolvers for specific fields in your schema. The code sample shows how to override the default mock for the 'hello' field in the Query type.

const { makeExecutableSchema } = require('@graphql-tools/schema');
const { addMocksToSchema } = require('@graphql-tools/mock');
const { graphql } = require('graphql');

const typeDefs = `
  type Query {
    hello: String
  }
`;

const schema = makeExecutableSchema({ typeDefs });
const mocks = {
  Query: () => ({
    hello: () => 'Hello, custom world!'
  })
};
const schemaWithMocks = addMocksToSchema({ schema, mocks });

const query = `
  query {
    hello
  }
`;

graphql(schemaWithMocks, query).then((result) =>
  console.log(result)
);

Using Mock List

This feature allows you to use MockList to generate a list of mock items with a specified range. The code sample demonstrates how to mock a list of users with a random length between 2 and 6.

const { makeExecutableSchema } = require('@graphql-tools/schema');
const { addMocksToSchema, MockList } = require('@graphql-tools/mock');
const { graphql } = require('graphql');

const typeDefs = `
  type Query {
    users: [User]
  }
  type User {
    id: ID
    name: String
  }
`;

const schema = makeExecutableSchema({ typeDefs });
const mocks = {
  Query: () => ({
    users: () => new MockList([2, 6])
  }),
  User: () => ({
    id: () => '1',
    name: () => 'John Doe'
  })
};
const schemaWithMocks = addMocksToSchema({ schema, mocks });

const query = `
  query {
    users {
      id
      name
    }
  }
`;

graphql(schemaWithMocks, query).then((result) =>
  console.log(result)
);