Deferring app initialization

Bolt offers a way to defer full initialization via the deferInitialization option and to call the equivalent App#init() in your code, putting more control over asynchronous execution required for initialization into your hands as the developer.

info

If you call start() before init(), Bolt will raise an exception.

const { App } = require('@slack/bolt');

// deferInitialization is one of the options you can set in the constructor
const app = new App({
  token,
  signingSecret,
  deferInitialization: true,
});

(async () => {
  try {
    // Must call init() before start() within an async function
    await app.init();
    // Now safe to call start()
    await app.start(process.env.PORT || 3000);
  } catch (e) {
    console.log(e);
    process.exit(1);
  }
})()