Set locale baseHref to '/' is not working with AngularNodeAppEngine

[eufri]

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

I have an application where English is the default locale and I don't want the prefix '/en' in the URL. With CommonEngine it was possible to set the baseHref in angular.json to '/' to achieve this.

      "i18n": {
        "sourceLocale": {
          "code": "en",
          "baseHref": "/"
        },
        "locales": {
          "de": "src/messages/messages.de.xlf",
          "es": "src/messages/messages.es.xlf"
        }
      }

Now I have migrated this application to Angular 19 and noticed that this does not seem to be possible anymore with AngularNodeAppEngine as the default locale 'en' is not recognized. The build is successful and all other locales work fine, except 'en'. Even the root path works, because the potentialLocale is '' (empty string) in this case, but no child routes can be found (at least not with ssr). Is this behavior expected? If so, are there still any workarounds to disable the locale prefix for a specific locale?

In a (maybe) naive approach, I tried adding the following line just before returning the entryPointExport in app-engine.ts#L146 and it worked, so it seems to be supported everywhere except in this particular location and therefore I really hope it's just a bug and I don't have to revert the migration.

if (!entryPoints.has(potentialLocale) && entryPoints.has("")) {
    return this.getEntryPointExports("");
}

Any help is appreciated, because everything else is already migrated.

Minimal Reproduction

Repo: https://github.com/eufri/angular-ssr-issue

Basically I have created a new app
ng new angular-ssr-issue --ssr --minimal --package-manager=yarn --routing --server-routing --skip-tests --ssr

Added localize package
ng add @angular/localize

And then added some test locales + messages and a child component +route

Exception or Error

Your Environment

Angular: 19.0.0
... animations, common, compiler, compiler-cli, core, forms
... localize, platform-browser, platform-browser-dynamic
... platform-server, router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1900.1
@angular-devkit/build-angular   19.0.1
@angular-devkit/core            19.0.1
@angular-devkit/schematics      19.0.1
@angular/cli                    19.0.1
@angular/ssr                    19.0.1
@schematics/angular             19.0.1
rxjs                            7.8.1
typescript                      5.6.3
zone.js                         0.15.0

Anything else relevant?

No response

[alan-agius4]

Although the baseHref is set to /, the files are emitted in /en, suggesting that this option might either be used incorrectly or there is another issue at play. In the case of a purely client-side application, the / path would not exist.

//cc @clydin

[eufri]

If I remember correctly, back when I wasn't using SSR, I simply delivered the files from /en, and it wasn't a problem because the baseHref was correct everywhere when set to '/'. That was a few years ago though.
My use case is that I just don't want a locale prefix to be added for a specific default locale. But if I understand you correctly, this was never actually officially supported? If not, is there any chance that this will be supported in the near future? If this will not be supported, I think you can close this issue and I'll look for other solutions to achieve this as I can't change the URLs anymore unfortunately.

[alan-agius4]

@eufri, I think in general we should support this use case better. I already have ideas, I'll try to open a PR earlier next week.

[eufri]

Thanks a lot @alan-agius4 ! If I can help you somehow, I am obviously happy to help, because I don't see any other (good) solutions and really need support for this.