Add Bazel build tool support

[subotic]

For Angular, adding Bazel should be fairly straightforward: https://angular.io/guide/bazel

[kilchenmann]

Adding bazel doesn't seem to be quite easy to implement. There are some issues with sass/scss especially with the material theming and with @angular/flex-layout.

I tried to fix it by following these issues:

• @angular/flex-layout: Bazel install fails
• bazelbuild/rules_sass: Add example of how to import from Angular Material's SASS stylesheets
• bazelbuild/rules_sass: Include_Import_issue

But ng s or ng build --leaveBazelFilesOnDisk still failing. I got the following errors:

ERROR: knora-app/src/BUILD.bazel:26:1: Compiling Sass failed (Exit 65)
Error: Can't find stylesheet to import.
  ╷
6 │ @import 'external/npm/node_modules/@angular/material/theming';
  │         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ╵
  src/assets/style/_theme.scss 6:9             @import
  src/app/main/login/login.component.scss 1:9  root stylesheet

Error: Can't find stylesheet to import.
  ╷
1 │ @import 'external/npm/node_modules/@angular/material/theming';
  │         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ╵
  src/app/project/ontology/ontology.component.scss 1:9  root stylesheet

[...]

I'm working on branch wip/add-bazel

[subotic]

Great, thanks. I will take a look. At first glance, this looks like a dependency configuration issue. Bazel is building everything in a sandbox, and if the external dependencies are not configured correctly, then stuff is missing in the sandbox.

[kilchenmann]

All you have to know about bazel:
https://youtu.be/J1lnp-nU4wM
or in the summary:
https://youtu.be/wYUQ0RtN7oc

Btw I will try to implement again after adding knora-api-js-lib

[flavens]

this issue has been moved to YouTrack: DSP-283