Bazel Maven migration Transitive Dependencies Scope - bazel

Question

I am trying to use the generate_workspace on one of the project which has deps and transitive dependencies. Once thegenerate_workspace.bzl has been generated and I copied it to the WORKSPACE and followed the instruction in the bazel docs. Though I see the deps and their transitive deps listed in the generate_workspace.bzl my project during java_library phase is not able resolve transitive deps.. when I import the same project in IDEA I don't see the jars correctly loaded.
My doubt is for the deps I see the generate_workspace.bzl is adding its transitve deps as runtime_deps which means they are available only during runtenter code hereime
I have created gist of all the files here
https://gist.github.com/kameshsampath/8a4bdc8b22d85bbe3f243fa1b816e464
Ideally in my maven project I just need https://gist.github.com/kameshsampath/8a4bdc8b22d85bbe3f243fa1b816e464#file-src_main_build-L8-L9, though generate_workspace.bzl has resolved rightly i thought its enough if my src/main/BUILD looks like
java_binary(
name = "main",
srcs = glob(["java/**/*.java"]),
resources = glob(["resources/**"]),
main_class = "com.redhat.developers.DemoApplication",
# FIXME why I should import all the jars when they are transitive to spring boot starter
deps = [
"//third_party:org_springframework_boot_spring_boot_starter_actuator",
"//third_party:org_springframework_boot_spring_boot_starter_web",
],
)
But sadly that gives lots of compilation errors as transitive deps are not getting loaded as part the above declaration. eventually I have to define like how I did in the https://gist.github.com/kameshsampath/8a4bdc8b22d85bbe3f243fa1b816e464#file-src_main_build
src_main_build is BUILD file under package src/main/BUILD
third_party_BUILD is the BUILD under package third_party/BUILD

Answer 1

Bazel expects you to declare all your direct dependencies. I.e. if you directly use a class from jar A, you need to have it in your direct dependencies.
What you are looking for is a deploy jar. This is a bit hacky but you can actually do it that way (in third_party/BUILD):
java_binary(
name = "org_springframework_boot_spring_boot_starter_actuator_bin",
main_class = "not.important",
runtime_deps = [":org_springframework_boot_spring_boot_starter_actuator"], )
java_import(
name = "springframework_actuator",
jars = [":org_springframework_boot_spring_boot_starter_actuator_bin_deploy.jar"],
)
This will bundle all dependencies except the neverlink one in a jar (the _deploy.jar) and reexpose it.

Answer 2

An update: rules_jvm_external is the officially maintained ruleset by the Bazel team to fetch and resolve artifacts transitively.
You can find the example for Spring Boot here. The declaration in the WORKSPACE file looks something like this:
load("#rules_jvm_external//:defs.bzl", "maven_install")
maven_install(
artifacts = [
"org.hamcrest:hamcrest-library:1.3",
"org.springframework.boot:spring-boot-autoconfigure:2.1.3.RELEASE",
"org.springframework.boot:spring-boot-test-autoconfigure:2.1.3.RELEASE",
"org.springframework.boot:spring-boot-test:2.1.3.RELEASE",
"org.springframework.boot:spring-boot:2.1.3.RELEASE",
"org.springframework.boot:spring-boot-starter-web:2.1.3.RELEASE",
"org.springframework:spring-beans:5.1.5.RELEASE",
"org.springframework:spring-context:5.1.5.RELEASE",
"org.springframework:spring-test:5.1.5.RELEASE",
"org.springframework:spring-web:5.1.5.RELEASE",
],
repositories = [
"https://jcenter.bintray.com",
]
)