Rollup/bundling doesn't work properly with the admin SDK

[Nicolai]

• Operating System version: macOS 14.3.1
• Firebase SDK version: 12.0.0
• Firebase Product: unsure exactly which product is failing, but app and/or messaging
• Node.js version: 18.19
• NPM version: 10.2.3

Describe the problem

Steps to reproduce:

Configure a project for rollup, something like this:

{
  "name": "project",
  "dependencies": {
    "firebase-admin": "^12.0.0"
  },
  "devDependencies": {
    "@rollup/plugin-node-resolve": "^15.2.3",
    "@rollup/plugin-typescript": "^11.1.6",
    "rollup": "^4.12.0",
    "typescript": "^5.3.3"
  },
  "engines": {
    "npm": ">=9.0.0",
    "node": ">=18.0.0"
  }
}

And in rollup.config.js

import typescript from '@rollup/plugin-typescript';
import { nodeResolve } from '@rollup/plugin-node-resolve';

export default {
    input: 'src/app.ts',
    output: {
        file: 'build/app.js',
        format: 'cjs',
    },
    plugins: [typescript(), nodeResolve()]
};

And an app that does anything like this:

import { initializeApp, cert } from "firebase-admin/app";
import { getMessaging } from "firebase-admin/messaging";

initializeApp({
    credential: cert({
        clientEmail: fcmClientEmail,
        privateKey: fcmPrivateKey,
        projectId: fcmProjectId
    }),
    databaseURL: fcmDatabaseUrl
});

// and so on...

Then try to build with rollup -c rollup.config.js, and you'll be met with:

src/app.ts → build/app.js...
[!] RollupError: "default" is not exported by "node_modules/firebase-admin/lib/app/index.js", imported by "node_modules/firebase-admin/lib/esm/app/index.js".
https://rollupjs.org/troubleshooting/#error-name-is-not-exported-by-module
node_modules/firebase-admin/lib/esm/app/index.js (1:7)

So either I'm a complete moron (which is not unlikely), or something isn't right here. I've researched it for a while now, and it seems I'm doing what I'm supposed to. I'm trying to rollup/treeshake the node application to make it as small as possible for a serverless function.

[Google Open Source Bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[Lahiru Maramba]

This looks like a rollupjs config issue to me. Can you play around with the @rollup/plugin-commonjs settings to see if that helps? Maybe start with requireReturnsDefault. See https://stackoverflow.com/a/74126843/1526201