Mercurius integration

Mercurius is a GraphQL adapter for Fastify. It is very simple to set up and does not require an HTTP adapter from InversifyJS.

You can simply create a Fastify instance, register Mercurius, and start the server.

import fastify, { FastifyInstance } from 'fastify';
import mercurius from 'mercurius';

const app: FastifyInstance = fastify();

const schema: string = `
  type Query {
    add(x: Int, y: Int): Int
  }
`;

const resolvers: mercurius.IResolvers<unknown, mercurius.MercuriusContext> = {
  Query: {
    add: async (_: unknown, { x, y }: { x: number; y: number }) => x + y,
  },
};

app.register(mercurius, {
  resolvers,
  schema,
});

await app.listen({ port: 3000 });

If you want to use the InversifyJS HTTP adapter, you can get the Fastify instance by calling adapter.build() and then register Mercurius.

For more information, please refer to the Mercurius documentation.