Schema validation failed with the following errors:
Data path \".builders[\'app-shell\']\" should have required property \'class\'.
Schema validation failed with the
Most of the answers are correct in stating that this occurs either because of a mismatch between:
OR
@angular-devkit/build-angular
version and angular versionAlso, this issue is most likely to occur if you either:
upgraded/downgraded nodejs version (which is no longer compatible with the angular version)
Upgraded angular version
Ran npm audit fix
For 1, check the nodejs version support needed here: https://angular.io/guide/setup-local and check the installed version. If you are using the latest version of angular, you should be able to make it work with the latest version of nodejs.
For 2, did you follow instructions here: https://update.angular.io/ ? If yes, and still have issues, look for any issues already created or create an issue here: https://github.com/angular/angular/issues
For 3, npm audit fix
updates the @angular-devkit/build-angular
version to a higher version because @angular-devkit/build-angular
does not follow proper versioning (major releases still update only the minor version). See here to check the compatible version for your angular version: https://www.npmjs.com/package/@angular-devkit/build-angular?activeTab=versions Use the correct version and the issue will be fixed.
P.S: This is a good read about angular versioning: https://angular.io/guide/releases