Mercurius is a GraphQL adapter for Fastify

Features:

• Caching of query parsing and validation.
• Automatic loader integration to avoid 1 + N queries.
• Just-In-Time compiler via graphql-jit.
• Subscriptions.
• Federation support via @mercuriusjs/federation, including Subscriptions.
• Gateway implementation via @mercuriusjs/gateway, including Subscriptions.
• Batched query support.
• Customisable persisted queries.

• Install
• Quick Start
• Examples
• API
• Context
• Loaders
• Hooks
• Lifecycle
• Federation
• Subscriptions
• Batched Queries
• Persisted Queries
• TypeScript Usage
• HTTP
• GraphQL over WebSocket
• Integrations
• Related Plugins
• Faq
• Acknowledgements
• License

npm i fastify mercurius graphql
# or
yarn add fastify mercurius graphql

The previous name of this module was fastify-gql (< 6.0.0).

'use strict'

const Fastify = require('fastify')
const mercurius = require('mercurius')

const app = Fastify()

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

const resolvers = {
  Query: {
    add: async (_, { x, y }) => x + y
  }
}

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

app.get('/', async function (req, reply) {
  const query = '{ add(x: 2, y: 2) }'
  return reply.graphql(query)
})

app.listen({ port: 3000 })

Check GitHub repo for more examples.

The project is kindly sponsored by:

• NearForm
• Platformatic

The Mercurius name was gracefully donated by Marco Castelluccio. The usage of that library was described in https://hacks.mozilla.org/2015/12/web-push-notifications-from-irssi/, and you can find that codebase in https://github.com/marco-c/mercurius.

MIT