const fastify = require("fastify");
const { RetryAgent, Agent } = require("undici");

const app = fastify();

let tries = 0;

app.get("/", (req, res) => {
  if (++tries % 2 !== 0) {
    return res.status(500).send("Test error");
  }

  res.send("Hello World");
});

app.server.on("connection", (socket) => {
  console.log("New connection");

  socket.on("close", () => {
    console.log("connection closed");
  });
});

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

  const a = new RetryAgent(new Agent({ connections: 1 }));
  const res = await a.request({
    origin: "http://localhost:3000",
    path: "/",
    method: "GET",
  });
  console.log(await res.body.text());
}
start();