Integration with Fastify

import fastify, { type FastifyReply, type FastifyRequest } from "fastify";
import { createGatewayRuntime, Logger } from "@graphql-hive/gateway-runtime";
import { PinoLogWriter } from "@graphql-hive/logger/writers/pino";

// Request ID header used for tracking requests
const requestIdHeader = "x-request-id";

// This is the fastify instance you have created
const app = fastify({
  logger: true,
  // Use our custom request id header
  requestIdHeader,
  // Align with Hive Gateway's request id log label
  requestIdLogLabel: "requestId",
  // Check the header first, then generate a new one if not found
  genReqId: (req): string =>
    req.headers[requestIdHeader]?.toString() || gw.fetchAPI.crypto.randomUUID(),
});

// This will allow us to access Fastify request and reply objects in the gateway
interface FastifyContext {
  req: FastifyRequest;
  reply: FastifyReply;
}

const gateway = createGatewayRuntime<FastifyContext>({
  // Use Fastify's logger (Pino) with Hive Logger
  logging: new Logger({
    writers: [new PinoLogWriter(app.log)],
  }),
  // Align with Fastify
  requestId: {
    // Use the same header name as Fastify
    headerName: requestIdHeader,
    // Use the request id from Fastify (see `FastifyContext`)
    generateRequestId: ({ context }) => context.req.id,
  },
  // Point to the supergraph
  supergraph: "./supergraph.graphql",
});

// Bind the gateway to Fastify
app.route({
  // "*" is recommendeded in order to handle landing page, readiness and other related endpoints
  url: "*",
  method: ["GET", "POST", "OPTIONS"],
  // Connect the gateway to Fastify route
  handler: (req, reply) =>
    gateway.handleNodeRequestAndResponse(req, reply, { req, reply }),
});

const port = 4000;

app.listen({ port, host: "0.0.0.0" }, (err) => {
  if (err) {
    console.error("Error starting gateway", err);
    process.exit(1);
  }
  console.log(`Gateway listening on port ${port}`);
});

// This will allow Fastify to forward multipart requests to Hive Gateway
app.addContentTypeParser("multipart/form-data", {}, (req, payload, done) =>
  done(null),
);