Make it convenient to run the "secondary umbrella" under bazel

i.e. `bazel run @rabbitmq-server-generic-unix-3.8.18//:broker` or
`bazel run @rabbitmq-server-generic-unix-3.8.18//:rabbitmqctl`

(cherry picked from commit 3e29763)

Author: HoloRin

BUILD.package_generic_unix

@@ -1,5 +1,6 @@
 load("@//:rabbitmq_package_generic_unix.bzl", "rabbitmq_package_generic_unix")
-load("@//:rabbitmq_run.bzl", "rabbitmq_run")
+load("@//:rabbitmq_run.bzl", "rabbitmq_run", "rabbitmq_run_command")
+load("@//:rabbitmqctl.bzl", "rabbitmqctl")
 
 rabbitmq_package_generic_unix(
     name = "broker-home",
@@ -16,3 +17,25 @@ rabbitmq_run(
     home = ":broker-home",
     visibility = ["//visibility:public"],
 )
+
+rabbitmq_run_command(
+    name = "broker",
+    rabbitmq_run = ":rabbitmq-run",
+    subcommand = "run-broker",
+)
+
+rabbitmqctl(
+    name = "rabbitmqctl",
+    home = ":broker-home",
+    # visibility = ["//visibility:public"],
+)
+
+rabbitmqctl(
+    name = "rabbitmq-diagnostics",
+    home = ":broker-home",
+)
+
+rabbitmqctl(
+    name = "rabbitmq-plugins",
+    home = ":broker-home",
+)

rabbitmq_home.bzl

@@ -142,3 +142,10 @@ rabbitmq_home = rule(
         "plugins": attr.label_list(),
     },
 )
+
+def _dirname(p):
+    return p.rpartition("/")[0]
+
+def rabbitmq_home_short_path(rabbitmq_home):
+    info = rabbitmq_home[RabbitmqHomeInfo]
+    return _dirname(_dirname(info.sbin[0].short_path))

rabbitmq_run.bzl

@@ -1,26 +1,18 @@
 load("@bazel-erlang//:erlang_home.bzl", "ErlangHomeProvider", "ErlangVersionProvider")
 load("@bazel-erlang//:bazel_erlang_lib.bzl", "path_join")
 load("@bazel-erlang//:ct.bzl", "sanitize_sname")
-load(":rabbitmq_home.bzl", "RabbitmqHomeInfo")
-
-def _dirname(p):
-    return p.rpartition("/")[0]
-
-def _rabbitmq_home_info_root_short_path(rabbitmq_home):
-    return _dirname(_dirname(rabbitmq_home.sbin[0].short_path))
+load(":rabbitmq_home.bzl", "RabbitmqHomeInfo", "rabbitmq_home_short_path")
 
 def _impl(ctx):
-    rabbitmq_home = ctx.attr.home[RabbitmqHomeInfo]
-
-    root = _rabbitmq_home_info_root_short_path(rabbitmq_home)
+    rabbitmq_home_path = rabbitmq_home_short_path(ctx.attr.home)
 
-    erl_libs = [path_join(root, "plugins")]
+    erl_libs = [path_join(rabbitmq_home_path, "plugins")]
 
     ctx.actions.expand_template(
         template = ctx.file._template,
         output = ctx.outputs.executable,
         substitutions = {
-            "{RABBITMQ_HOME}": root,
+            "{RABBITMQ_HOME}": rabbitmq_home_path,
             "{ERL_LIBS}": ":".join(erl_libs),
             "{ERLANG_HOME}": ctx.attr._erlang_home[ErlangHomeProvider].path,
             "{SNAME}": sanitize_sname("sbb-" + ctx.attr.name),

rabbitmqctl.bzl

@@ -1,15 +1,15 @@
 load("@bazel-erlang//:erlang_home.bzl", "ErlangVersionProvider")
-load(":rabbitmq_home.bzl", "RabbitmqHomeInfo")
+load(":rabbitmq_home.bzl", "RabbitmqHomeInfo", "rabbitmq_home_short_path")
 
 def _impl(ctx):
     erlang_version = ctx.attr._erlang_version[ErlangVersionProvider].version
 
-    rabbitmq_home = ctx.attr.home[RabbitmqHomeInfo]
+    rabbitmq_home_path = rabbitmq_home_short_path(ctx.attr.home)
 
     script = """
     exec ./{home}/sbin/{cmd} $@
     """.format(
-        home = ctx.attr.home.label.name,
+        home = rabbitmq_home_path,
         cmd = ctx.label.name,
     )