angular report server dependencies as not esm

[robertIsaac]

Command

build

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

when building using application builder with SSR Angular warn about node dependencies
this is the same as my problem
firebase/firebase-js-sdk#7914
by removing the server configuration this warning disappear

expected behavior
not to show warning about node modules

Minimal Reproduction

1. generate new angular project with SSR
2. ng add @angular/fire and choose Authentication
3. run ng build

Exception or Error

▲ [WARNING] Module 'undici' used by 'node_modules/@firebase/auth/dist/node-esm/index.js' is not ESM

  CommonJS or AMD dependencies can cause optimization bailouts.
  For more information see: https://angular.io/guide/build#configuring-commonjs-dependencies

Your Environment

Angular CLI: 17.3.6
Node: 20.11.0
Package Manager: npm 10.4.0
OS: win32 x64

Angular: 17.3.6
... animations, cli, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, platform-server
... router, ssr

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1703.6
@angular-devkit/build-angular   17.3.6
@angular-devkit/core            17.3.6
@angular-devkit/schematics      17.3.6
@angular/fire                   17.0.1
@schematics/angular             17.3.6
rxjs                            7.8.1
typescript                      5.4.5
zone.js                         0.14.4

Anything else relevant?

No response

[JoostK]

undici is, in fact, a CJS module: https://unpkg.com/browse/undici@6.14.1/index.js. AFAICS undici is not a Node builtin; it being the backing implementation for Node's fetch global doesn't necessarily mean that importing undici leverages the same built in Undici module.

[robertIsaac]

undici is, in fact, a CJS module: https://unpkg.com/browse/undici@6.14.1/index.js. AFAICS undici is not a Node builtin; it being the backing implementation for Node's fetch global doesn't necessarily mean that importing undici leverages the same built in Undici module.

I might have misunderstand the warning, but I feel the main purpose of showing the warning is the browser bundle size, which means if the package is used only in SSR then it shouldn't warn since the browser bundle size is unaffected

[alan-agius4]

Though mainly linked to enhancing front-end performance, ESM treeshaking proves valuable for server-side applications for these key reasons:

1. Smaller, Efficient Bundles: By removing unused code, treeshaking shrinks server bundles. This leads to:

   • Quicker Server Startup: Less code to process means the server gets up and running faster.
   • Reduced Memory Use: Smaller bundles demand less memory from the server, enhancing its efficiency.

2. Cost-Effective Serverless: Serverless functions or Edge workers (e.g., AWS Lambda, Google Cloud Functions, CloudFlare Pages) are becoming increasingly popular. These functions are billed based on execution time and memory consumption. By minimizing code size through treeshaking, you can directly reduce the costs associated with serverless deployments.

Hence, while the impact of smaller bundles might not be as noticeable in server-side applications as in client-side scenarios, the benefits are still tangible. They include faster startup times, reduced resource consumption and cost savings in serverless environments.