如何在 Bazel 规则中运行其他规则的可执行文件？

Question

假设我有一个自定义规则，my_object. 看起来像：

my_object(
  name = "foo",
  deps = [
    //services/image-A:push,
    //services/image-B:push,
  ]
)

其中标签deps是rules_docker的container_push规则。

我希望能够bazel run //:foo并让它在deps列表中推送 Docker 镜像。我该怎么做呢？

这似乎是一个特定情况，通常只是希望在自定义规则的可执行文件中运行其他规则的可执行文件。

Answer 1

这里要做的事情是my_object输出一个可执行其他可执行文件的可执行文件。

考虑这个例子：

def _impl1(ctx):
  ctx.actions.write(
    output = ctx.outputs.executable,
    is_executable = True,
    content = "echo %s 123" % ctx.label.name)
  return DefaultInfo(executable = ctx.outputs.executable)


exec_rule1 = rule(
  implementation = _impl1,
  executable = True,
)


def _impl2(ctx):

  executable_paths = []
  runfiles = ctx.runfiles()
  for dep in ctx.attr.deps:
    # the "./" is needed if the executable is in the current directory
    # (i.e. in the workspace root)
    executable_paths.append("./" + dep.files_to_run.executable.short_path)
    # collect the runfiles of the other executables so their own runfiles
    # will be available when the top-level executable runs
    runfiles = runfiles.merge(dep.default_runfiles)

  ctx.actions.write(
    output = ctx.outputs.executable,
    is_executable = True,
    content = "\n".join(executable_paths))

  return DefaultInfo(
    executable = ctx.outputs.executable,
    runfiles = runfiles)


exec_rule2 = rule(
  implementation = _impl2,
  executable = True,
  attrs = {
    "deps": attr.label_list(),
  },
)

BUILD.bazel：

load(":defs.bzl", "exec_rule1", "exec_rule2")

exec_rule1(name = "foo")
exec_rule1(name = "bar")
exec_rule2(name = "baz", deps = [":foo", ":bar"])

然后运行它：

$ bazel run //:baz
INFO: Analyzed target //:baz (4 packages loaded, 19 targets configured).
INFO: Found 1 target...
Target //:baz up-to-date:
  bazel-bin/baz
INFO: Elapsed time: 0.211s, Critical Path: 0.01s
INFO: 0 processes.
INFO: Build completed successfully, 6 total actions
INFO: Build completed successfully, 6 total actions
foo 123
bar 123