@dzangolab/fastify-mercurius

A Fastify plugin that provides an easy integration of mercurius graphql server in a fastify API.

The plugin is a thin wrapper around the mercurius plugin.

Requirements

• @dzangolab/fastify-config
• @dzangolab/fastify-slonik
• graphql
• mercurius
• mercurius-codegen
• slonik

Installation

In a simple repo:

npm install @dzangolab/fastify-mercurius graphql mercurius mercurius-codegen

If using in a monorepo with pnpm:

pnpm add --filter "myrepo" @dzangolab/fastify-mercurius graphql mercurius mercurius-codegen

Usage

Add a mercurius block to your config:

import { parse } from "@dzangolab/fastify-config";
import dotenv from "dotenv";

import { resolvers, schema } from "path/to/graphql";

import type { ApiConfig } from "@dzangolab/fastify-config";

dotenv.config();

const config: ApiConfig = {
  ...
  mercurius: {
    enabled: parse(process.env.MERCURIUS_GRAPHQL_ENABLED, true) as boolean,
    graphiql: parse(process.env.MERCURIUS_GRAPHIQL_ENABLED, false) as boolean,
    path: parse(process.env.GRAPHQL_PATH, "/graphql") as string,
    resolvers,
    schema,
  },
  ...
};

export default config;

Register the plugin with your Fastify instance:

import configPlugin from "@dzangolab/fastify-config";
import mercuriusPlugin from "@dzangolab/fastify-mercurius";
import fastify from "fastify";

import config from "./config";

import type { ApiConfig } from "@dzangolab/fastify-config";
import type { FastifyInstance } from "fastify";

// Create fastify instance
const fastify = Fastify({
  logger: config.logger,
});

// Register fastify-config plugin
fastify.register(configPlugin, { config });

// Register fastify-mercurius plugin
fastify.register(mercuriusPlugin);

await fastify.listen({
  port: config.port,
  host: "0.0.0.0",
 });

Configuration

The mercurius block in the ApiConfig supports all of the original mercurius plugin's options.

An additional enabled (boolean) option allows you to disable the graphql server.

Context

The fastify-mercurius plugin will generate a graphql context on every request that will include the following attributes:

Attribute	Type	Description
config	ApiConfig	The fastify servers' config (as per @dzangolab/fastify-config)
database	Database	The fastify server's slonik instance (as per @dzangolab/fastify-slonik)
sql	SqlTaggedTemplate	The fastify server's sql tagged template from slonik