Dev Server throws error when running Angular 17 app non-standalone with SSR

[griest024]

Command

serve

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

16

Description

When running an Angular 17 app with the module setup and SSR enabled, the dev server throws an error.

Building (ng b) works (unless prerender: true) and serving the client bundle directly works as well as running SSR: node dist/repro-app/server/server.mjs.

With prerender enabled, building throws the same error as the dev server.

Removing SSR (deleting ssr and server options in angular.json) causes the dev server to work as expected.

Minimal Reproduction

Run ng s in my repro.

See this branch for a repro of how removing SSR options fixes the issue.

Exception or Error

[vite] Internal server error: Cannot read properties of undefined (reading 'ɵmod')
      at getNgModuleDef (/workspace/repro-app/node_modules/@angular/core/fesm2022/core.mjs:2117:25)
      at assertNgModuleType (/workspace/repro-app/node_modules/@angular/core/fesm2022/core.mjs:2371:10)
      at compileNgModuleFactory (/workspace/repro-app/node_modules/@angular/core/fesm2022/core.mjs:31582:18)
      at _PlatformRef.bootstrapModule (/workspace/repro-app/node_modules/@angular/core/fesm2022/core.mjs:32472:16)
      at eval (/workspace/repro-app/node_modules/@angular/platform-server/fesm2022/platform-server.mjs:17111:39)
      at Generator.next (<anonymous>)
      at eval (/workspace/repro-app/.angular/vite-root/repro-app/chunk-VPSODEBW.mjs:64:61)
      at ZoneAwarePromise (/workspace/repro-app/node_modules/zone.js/fesm2015/zone-node.js:1353:21)
      at Module.__async (/workspace/repro-app/.angular/vite-root/repro-app/chunk-VPSODEBW.mjs:48:10)
      at renderModule (/workspace/repro-app/node_modules/@angular/platform-server/fesm2022/platform-server.mjs:17100:50)

Your Environment

_                      _                 ____ _     ___
    / \   _ __   __ _ _   _| | __ _ _ __     / ___| |   |_ _|
   / △ \ | '_ \ / _` | | | | |/ _` | '__|   | |   | |    | |
  / ___ \| | | | (_| | |_| | | (_| | |      | |___| |___ | |
 /_/   \_\_| |_|\__, |\__,_|_|\__,_|_|       \____|_____|___|
                |___/
    

Angular CLI: 17.1.0
Node: 18.19.0
Package Manager: npm 10.2.3
OS: linux x64

Angular: 17.1.0
... animations, cli, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, platform-server
... router, ssr

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1701.0
@angular-devkit/build-angular   17.1.0
@angular-devkit/core            17.1.0
@angular-devkit/schematics      17.1.0
@schematics/angular             17.1.0
rxjs                            7.8.1
typescript                      5.2.2
zone.js                         0.14.3

Anything else relevant?

Maybe this isn't a supported usage since standalone is default now? Seems like modules should still be fully supported until they're officially deprecated.

[alan-agius4]

The problem is caused because when updated the main.server.ts manually the default export in https://github.com/griest024/ng17-repro/blob/c54b47df03c804f8c39ed290efd930e3e4ff5eb5/src/main.server.ts#L1 has been removed.

You could update it the below if you'd also want to keep the named export.

 export {AppServerModule, AppServerModule as default} from './app/app.server.module';

We should however provide a more actionable error message here.

[griest024]

@alan-agius4 That fixed it! Good call. I definitely support a better error message.