v4.1.1 has inconsistent types with express v5

[nickdirienzo]

@slack/bolt version

4.1.1

Your App and Receiver Configuration

N/A

Node.js runtime version

v21.7.3

Steps to reproduce:

Install @slack/bolt latest which installs express v5. The express types are set to ^4 in @slack/bolt's package.json but these aren't aligned with the version of Express being used.

Expected result:

@types/express should be 5.0.0 if Express v5 is used as far as I know.

Actual result:

@types/express v4 is used even though express v5 is installed.

Requirements

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[zimeg]

Hey @nickdirienzo 👋 Thanks for catching this!

As I understand, the major version of @types/express should match express which is done in #2355. That PR also moves this into devDependencies since I believe it's used during development of bolt-js itself and not during app development.

Could you share how you stumbled into this? I'm wondering if it was caused by incompatible @types/express and express versions, but haven't run into this myself 🤔

[nickdirienzo]

Thanks for jumping on this so quickly @zimeg! I didn't realize @types/express was pinned to ^4, so in our package.json we had it on 5.0.0 because of the express 5 upgrade. It looks like that PR should resolve the typing issue 🙏

What we're seeing in our development experience is we have a function like this:

import { json as JsonMiddleware, type IRouter, Router } from "express";

// This is getting typed with v5
export const setupApiRoutes = (router: IRouter) => {
	router.use("/v1", apiRouter);
};

Trying to pass in receiver.router causes TS to think a v4 Express router is being passed in even though it expects a v5 one... 😅

import { App, ExpressReceiver } from "@slack/bolt";

const receiver = new ExpressReceiver({
	signingSecret: env.SLACK_SIGNING_SECRET,
	clientId: env.SLACK_CLIENT_ID,
	clientSecret: env.SLACK_CLIENT_SECRET,
	stateSecret: env.SLACK_STATE_SECRET,
	scopes,
	installerOptions: {
		directInstall: true,
	},
	installationStore: InstallationStore,
});

// This errors for us in our IDE
setupApiRoutes(receiver.router);

[zimeg]

🎉 Thanks so much for sharing this snippet! I can confirm the latest changes fix the compilation error this was causing.

We have a release candidate prepared for the next patch version in #2347 which is undergoing testing now, but I'm hoping to land this change with the next release soon!

[nickdirienzo]

So speedy! Thanks for following up on this so quickly!