Customize Bootstrap

We use npm start or node production.js to bootstrap application. Though we can add application logic inside these two files, but it isn't recommanded. System proivde other entries for adding bootstrap behavious.


System will load file under src/boostrap/ which are:

  • Master process will load src/bootstrap/master.js
  • Each worker processes will load src/bootstrap/worker.js

So we can put bootstrap related code inside these two files respectively.

If there are code need to be called in both Master and Woker process, you can extract it into a seperate file and require it in both master.js and worker.js.

// src/bootstrap/common.js
global.commonFn = function(){


// src/bootstrap/master.js

// src/boostrap/worker.js


If you want to add logic before node start http server. For example, to read configuration from database, or read a dataset from remote host. think.beforeStartServer is design for this scenario:

think.beforeStartServer(async () => {
  const data = await getDataFromApi();
  think.config(key, data);

think.beforeStartServer allows to register multiple callbacks, it also accepts a Promise which means you can use async/await to perform a asynchronous operation.

System will not start until all registered callbacks are finished. of cause there is a timeout limit. You can set the timeout value by configure startServerTimeout which is 3 seconds by default.

module.exports = {
  startServerTimeout: 5000 // change timeout to 5s

Customize http service

By default system create http service by calling Koa's listen method, you can also customize it by using createServer configure.

// src/config/config.js
const https = require('https');
const fs = require('fs');

const options = {
  key: fs.readFileSync('test/fixtures/keys/agent2-key.pem'),
  cert: fs.readFileSync('test/fixtures/keys/agent2-cert.pem')

module.exports = {
  // just create service, no listen
  createServer: function(callback){
    return https.createServer(options, callback);

You can get http service instance in

appReady event

After http service is created, it will fire appReady event. To register it, use"appReady")."appReady", () => {
  const server =;