Solvedangular cli Angular 6 app with angular library: ng build works but ng build --prod throws "ERROR in ./src/app/app.component.ngfactory.js"

Bug Report or Feature Request (mark with an x)

- [x] bug report -> please search issues before submitting
- [ ] feature request

Area

- [x] devkit
- [ ] schematics

Versions

node v8.10.0
npm 6.1.0
macOS High Sierra
"@angular/core": "^6.0.3",
"@angular/cli": "~6.0.8",

Repro steps

I created an angular library ng generate library common-lib --prefix=canyalib

Added these components and services to the library module

Exported them in the public_api.ts

Used the library components successfully in the project app

The CommonLibModule is imported in the app.module.ts

I run ng serve and ng build without errors. But when I run ng serve --prod or ng build --prod. The build fails after the 92% ... UglifyTask :

The log given by the failure

ERROR in ./dist/common-lib/canyaio-common-lib.ngfactory.js
Module not found: Error: Can't resolve '@canyaio/common-lib' in '/Users/GustavoIbarra/Projects/Angular/canya-common/dist/common-lib'
ERROR in ./src/app/app.module.ngfactory.js
Module not found: Error: Can't resolve '@canyaio/common-lib' in '/Users/GustavoIbarra/Projects/Angular/canya-common/src/app'
ERROR in ./src/app/app.component.ngfactory.js
Module not found: Error: Can't resolve '@canyaio/common-lib' in '/Users/GustavoIbarra/Projects/Angular/canya-common/src/app'

Desired functionality

This error won't let me run the app with library modules in a production environment.

Mention any other details that might be useful

If I import the packaged library in an external Angular 6 application, the same happens: ng serve or ng build lets the app run without problems. ng serve --prod or ng build --prod fails.

Can you check if this has the same effect

npm run ng build -- --prod

i have encountered same issue. Check your aot build of library. Check its metadata.json file, importAs:"libname", it should be "@libname". that why ngfactory.js searching for "libname" rather than "@libname".

so solution is change package.json of your library. 'name' property should be "@libname".

Thanks @daniel-nagy
I encountered this issue and got it resolved by adding another path in tsconfig.json.
ngfactory is looking for the name defined in library's package.json. It could be different from the original name used to create the library using angular cli.
matching the path like below resolved the issue (@my-repo/my-lib is the package name defined in library package.json).

"paths": {
      "my-lib": [
        "dist/my-lib"
      ],
      "@my-repo/my-lib": [
        "dist/my-lib"
      ],
      "my-lib/*": [
        "dist/my-lib/*"
      ]
    }

Incase someone else lands here, I had the same issue but my problem was I prefixed the path with an @ in my tsconfig.json file. Development builds worked find but when building for production I got the following error:

ERROR in ./dist/my-library/my-library.ngfactory.js
Module not found: Error: Can't resolve 'my-library' in '/path/to/MyWorkSpace/dist/my-library'
ERROR in ./src/app/app.module.ngfactory.js
Module not found: Error: Can't resolve 'my-library' in '/path/to/MyWorkSpace/src/app'

As you can see, the generated factory classes are looking for my-library, not @my-library. I just removed the @ from my path mappings and it built fine.