- Upgrade bazel
- Reduce the number of places where bazel version needs to be upgraded
in future.
- also make sure the list of bazel versions to test by bazelified tests
is loaded from supported_versions.txt (it was hardcoded before).
- ~~Try upgrading windows RBE build to bazel 6.3.2 as well.~~
The core idea:
- the source of truth for supported bazel versions is in
`bazel/supported_versions.txt`
- the first version listed in `bazel/supported_versions.txt` is
considered to be the "primary" bazel version and is going to be used in
most places thoroughout the repo.
- use templates to include the primary bazel version in testing
dockerfiles and in a newly introduced `.bazelversion` files (which gets
loaded by our existing `tools/bazel` wrapper).
~~Supersedes https://github.com/grpc/grpc/pull/33880~~
Oops I missed important changes from
https://github.com/grpc/grpc/pull/32712. And it turned out that there
are two problems that I couldn't fix at this point.
- Windows Bazel RBE Linker Error: This may be caused by how new Bazel 6
invokes build tools chain but it's not clear. I put workaround to use
Bazel 5 by using `OVERRIDE_BAZEL_VERSION=5.4.1`
- Rule `rules_pods` to fetch CronetFramework from CocoaPod has
incompatibility with sort of built-in apple toolchain.
(https://github.com/bazel-xcode/PodToBUILD/issues/232): I couldn't find
a workaround to fix this so I ended up disabling all tests depending
this target.
Jan Tattermusch