server.js

const fastify = require("fastify");
const func = require("./index").handler;

const normalizeQueryParams = (query) => {
  let q = {};
  for (const [key, val] of Object.entries(query)) {
    q[key] = Array.isArray(val) ? val : [val];
  }
  return q;
};

const createServer = ({ logger = true } = {}) => {
  const server = fastify({ logger });
  server.get("/*", async (request, reply) => {
    if (request.params["*"] === "favicon.ico") return reply.send("");
    const event = {
      rawPath: request.params["*"],
      path: request.params["*"],
      multiValueQueryStringParameters: normalizeQueryParams(request.query),
      requestContext: {
        http: {
          method: "GET",
          path: request.params["*"],
        },
      },
      headers: request.headers,
      isBase64Encoded: false,
    };
    const result = await func(event, {}, false);
    reply.headers(result.headers).status(result.statusCode).send(result.body);
  });
  return server;
};

module.exports = createServer;

if (!module.parent) {
  const server = createServer();
  server.listen(4001);
}