Adding custom HTTP routes

As of v3.7.0, custom HTTP routes can be easily added by passing in an array of routes as customRoutes when initializing App.

Each CustomRoute object must contain three properties: path, method, and handler. method, which corresponds to the HTTP verb, can be either a string or an array of strings.

Since v3.13.0, the default built-in receivers (HTTPReceiver and SocketModeReceiver) support dynamic route parameters like Express.js does. With this, you can capture positional values in the URL for use in your route's handler via req.params.

To determine what port the custom HTTP route will be available on locally, you can specify an installerOptions.port property in the App constructor. Otherwise, it will default to port 3000.

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

// Initialize Bolt app, using the default HTTPReceiver
const app = new App({
  token: process.env.SLACK_BOT_TOKEN,
  signingSecret: process.env.SLACK_SIGNING_SECRET,
  customRoutes: [
    {
      path: '/health-check',
      method: ['GET'],
      handler: (req, res) => {
        res.writeHead(200);
        res.end(`Things are going just fine at ${req.headers.host}!`);
      },
    },
    {
      path: '/music/:genre',
      method: ['GET'],
      handler: (req, res) => {
        res.writeHead(200);
        res.end(`Oh? ${req.params.genre}? That slaps!`);
      },
    },
  ],
  installerOptions: {
    port: 3001,
  },
});

(async () => {
  await app.start();
  console.log('⚡️ Bolt app started');
})();

Custom ExpressReceiver routes

Adding custom HTTP routes is quite straightforward when using Bolt’s built-in ExpressReceiver. Since v2.1.0, ExpressReceiver added a router property, which exposes the Express Router on which additional routes and middleware can be added.

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

// Create a Bolt Receiver
const receiver = new ExpressReceiver({ signingSecret: process.env.SLACK_SIGNING_SECRET });

// Create the Bolt App, using the receiver
const app = new App({
  token: process.env.SLACK_BOT_TOKEN,
  receiver
});

// Slack interactions are methods on app
app.event('message', async ({ event, client }) => {
  // Do some slack-specific stuff here
  await client.chat.postMessage(...);
});

// Middleware methods execute on every web request
receiver.router.use((req, res, next) => {
  console.log(`Request time: ${Date.now()}`);
  next();
});

// Other web requests are methods on receiver.router
receiver.router.post('/secret-page', (req, res) => {
  // You're working with an express req and res now.
  res.send('yay!');
});

(async () => {
  await app.start();
  console.log('⚡️ Bolt app started');
})();