maven version expanded

[knarukulla]

Issue: #618

Solution:

Expand maven version using bazel variables to publishing maven artifact to repo.
bazel run --stamp
--define "maven_repo=<>
--define "maven_user=<>"
--define "maven_password=<>"
--define "maven_version=<>"
//src/main/java/com/xxx/example:

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[knarukulla]

@cheister could you please review my PR? and also how can i get past the pipeline errors

[cj81499]

@knarukulla have you signed the CLA? I imagine that @cheister may be waiting until that's done before reviewing.

[shs96c]

expand_make_variables is marked as deprecated, but I can see this being useful since we don't actually know the variables we are replacing. LGTM.

Thank you for the PR!

[hisener]

👋 Hi @shs96c, is there a plan to cut a new release soon? I am interested in this change to (partially) replace the solution in #618 (comment).

However, I have two questions related to this change:

1. If we start using maven_coordinates = "com.datadog.foo:$(maven_version), will this tag be inaccurate since we don't replace the variable in https://github.com/bazelbuild/rules_jvm_external/blob/5d266dd75c4677aeb86ea6c0b23542c114689362/private/rules/java_export.bzl#L69
2. Do we also need to call in expand_make_variables in maven_bom_fragment? https://github.com/bazelbuild/rules_jvm_external/blob/5d266dd75c4677aeb86ea6c0b23542c114689362/private/rules/maven_bom_fragment.bzl#L32

[shs96c]

We probably do need to expand the tag in maven_bom_fragment too. Good catches.

[shs96c]

We are working on the next release too: #831

[hisener]

We probably do need to expand the tag in maven_bom_fragment too. Good catches.

I can file a PR for the maven_bom_fragment rule, but not sure what to do about the tag since it's in the java_export macro.

[shs96c]

I can take a look at that.