bazel: incompatible_remove_native_maven_jar

The native maven_jar rule will no longer be available with this flag set to true.

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(Update: managed by @jin as of July 12)

A migration tool will be provided to automatically convert maven_jar targets to rules_jvm_external’s maven_install rule, and modify BUILD files to use the new labels.

See https://docs.google.com/document/d/1CqxPv-TwvFWBHgtg7_QhVfck4vH4rnmCU_IuMdC7O2M/edit# for a design document of this migration tool.

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Proposal by @dkelmer as of Nov 28, which is another valid migration solution that is done manually:

Use

load("@bazel_tools//tools/build_defs/repo:java.bzl", "java_import_external")

or the convenience wrapper

load("@bazel_tools//tools/build_defs/repo:jvm.bzl", "jvm_maven_import_external")

instead.

Given a WORKSPACE file that looks like the following:

maven_jar(
    name = "truth",
    artifact = "com.google.truth:truth:0.30",
    sha1 = "9d591b5a66eda81f0b88cf1c748ab8853d99b18b",
)

It will need to look like this after updating:

load("@bazel_tools//tools/build_defs/repo:jvm.bzl", "jvm_maven_import_external")
jvm_maven_import_external(
    name = "truth",
    artifact = "com.google.truth:truth:0.30",
    artifact_sha256 = "59721f0805e223d84b90677887d9ff567dc534d7c502ca903c0c2b17f05c116a",
    server_urls = ["http://central.maven.org/maven2"],
    licenses = ["notice"],  # Apache 2.0
)

Notably

• the licenses attribute is mandatory
• sha1 is no longer supported, only sha256 is
• the server_urls attribute is mandatory. If your maven_jar rule did not specify a url then you should use the default server (“http://central.maven.org/maven2”). If your rule did specify a url then keep using that one.