Function createServer

lib/server.js:27–149

(options, httpHandler)

}

function createServer (options, httpHandler) {
  const server = getServerInstance(options, httpHandler)

  // `this` is the Fastify object
  function listen (
    listenOptions = { port: 0, host: 'localhost' },
    cb = undefined
  ) {
    if (typeof cb === 'function') {
      if (cb.constructor.name === 'AsyncFunction') {
        FSTWRN003('listen method')
      }

      listenOptions.cb = cb
    }
    if (listenOptions.signal) {
      if (typeof listenOptions.signal.on !== 'function' && typeof listenOptions.signal.addEventListener !== 'function') {
        throw new FST_ERR_LISTEN_OPTIONS_INVALID('Invalid options.signal')
      }

      // copy the current signal state
      this[kState].aborted = listenOptions.signal.aborted

      if (this[kState].aborted) {
        return this.close()
      } else {
        const onAborted = () => {
          this[kState].aborted = true
          this.close()
        }
        listenOptions.signal.addEventListener('abort', onAborted, { once: true })
      }
    }

    // If we have a path specified, don't default host to 'localhost' so we don't end up listening
    // on both path and host
    // See https://github.com/fastify/fastify/issues/4007
    let host
    if (listenOptions.path == null) {
      host = listenOptions.host ?? 'localhost'
    } else {
      host = listenOptions.host
    }
    if (!Object.hasOwn(listenOptions, 'host') ||
      listenOptions.host == null) {
      listenOptions.host = host
    }
    if (host === 'localhost') {
      listenOptions.cb = (err, address) => {
        if (err) {
          // the server did not start
          cb(err, address)
          return
        }

        multipleBindings.call(this, server, httpHandler, options, listenOptions, () => {
          this[kState].listening = true
          cb(null, address)