[antlir2][migration] move configuration to PACKAGE file

Summary: This is available to use now - do this instead of the hacky package comparison.

Test Plan: waitforsandcastle

Reviewed By: pallotron

Differential Revision: D50192650

fbshipit-source-id: 3e715404c4d3b337efe35f0e53699af5048863a0

antlir/bzl/antlir2_migration.bzl

@@ -0,0 +1,26 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+load("//antlir/bzl:types.bzl", "types")
+
+mode_t = enum("none", "shadow")
+
+def _configure_package(*, mode: str | mode_t):
+    if types.is_string(mode):
+        mode = mode_t(mode)
+    write_package_value(
+        "antlir2.migration",
+        mode,
+        overwrite = True,
+    )
+
+def _get_mode() -> mode_t:
+    return read_package_value("antlir2.migration") or mode_t("none")
+
+antlir2_migration = struct(
+    configure_package = _configure_package,
+    get_mode = _get_mode,
+    mode_t = mode_t,
+)

antlir/bzl/antlir2_shim.bzl

@@ -4,41 +4,14 @@
 # LICENSE file in the root directory of this source tree.
 
 load("//antlir/bzl:build_defs.bzl", "export_file")
+load(":antlir2_migration.bzl?v2_only", "antlir2_migration")
 load(":build_defs.bzl", "is_buck2", "python_unittest")
 load(":flavor.shape.bzl", "flavor_t")
 load(":target_helpers.bzl", "antlir_dep")
 load(":types.bzl", "types")
 
 types.lint_noop(flavor_t)
 
-_DEFAULT_ENABLED_PACKAGES = [
-    "antlir/bzl/linux",
-    "antlir/linux",
-    "bot_generated/antlir/fbpkg/db",
-    "kernel/kernels",
-    "metalos",
-    "netos",
-    "os_foundation",
-    "sandcastle/images",
-    "tupperware/image/features",
-    "tupperware/image/base",
-    "tupperware/image/rpmbuild",
-    "tupperware/image/webfoundation",
-    "tupperware/image/multifeed",
-]
-
-_DEFAULT_DISABLED_PACKAGES = [
-    # fbcode/antlir just has way too many weird and broken images, don't even
-    # try to make antlir2 images for them when the goal is to delete it all soon
-    # enough anyway
-    "antlir",
-    "sandcastle/images/runtime",
-    "sandcastle/images/worker",
-    "tupperware/cm/antlir/tests",
-    "tupperware/cm/tests",
-    "tupperware/image/slimos",
-]
-
 def _antlir2_setting_buck1(x):
     return x
 
@@ -47,7 +20,7 @@ antlir2_setting = native.enum(
     "yes",  # enable antlir2 shadow
     "no",  # disable antlir2 without a recorded reason
     "chef",  # disable antlir2 because chef is natively supported
-    "debuginfo",  # antlir2 does not yet support this TODO(T153698233)
+    "debuginfo",  # antlir2 natively supports this
     "extract",  # native antlir2 feature
     "rpmbuild",  # antlir2 does not allow rpm installation during a genrule
     # user wants to explicitly alias a built layer instead of downloading it from fbpkg
@@ -56,50 +29,19 @@ antlir2_setting = native.enum(
     "test",
 ) if is_buck2() else _antlir2_setting_buck1
 
-def _antlir2_or_default(antlir2: antlir2_setting | None, default: bool) -> bool:
-    if antlir2 != None:
-        return antlir2 == antlir2_setting("yes")
-    else:
-        return default
-
-_FLAVOR_T = types.optional(types.union(
-    types.str,
-    types.shape(flavor_t),
-))
+def _should_shadow(antlir2: str | bool | None) -> bool:
+    if antlir2 == None and is_buck2():
+        package_mode = antlir2_migration.get_mode()
+        return package_mode == antlir2_migration.mode_t("shadow")
 
-types.lint_noop(_FLAVOR_T)
+    # otherwise, PACKAGE value takes a back-seat to the explicit 'antlir2' flag
 
-def _should_make_parallel(
-        antlir2: str | bool | None,
-        *,
-        flavor: _FLAVOR_T = None,
-        disabled_packages: list[str] = _DEFAULT_DISABLED_PACKAGES,
-        enabled_packages: list[str] = _DEFAULT_ENABLED_PACKAGES) -> bool:
     if types.is_bool(antlir2):
         antlir2 = antlir2_setting("yes" if antlir2 else "no")
     else:
         antlir2 = antlir2_setting(antlir2) if antlir2 else None
 
-    # TODO(vmagro): make True the default
-    result = False
-
-    # Find the "closest" match so that _DEFAULT_{ENABLED,DISABLED}_PACKAGES can
-    # peacefully co-exist
-    distance = 999999999
-    for pkg in enabled_packages:
-        if native.package_name() == pkg or native.package_name().startswith(pkg + "/"):
-            this_distance = len(native.package_name()[len(pkg):].split("/"))
-            if this_distance < distance:
-                result = _antlir2_or_default(antlir2, True)
-                distance = this_distance
-    for pkg in disabled_packages:
-        if native.package_name() == pkg or native.package_name().startswith(pkg + "/"):
-            this_distance = len(native.package_name()[len(pkg):].split("/"))
-            if this_distance < distance:
-                result = _antlir2_or_default(antlir2, False)
-                distance = this_distance
-
-    return result
+    return antlir2 == antlir2_setting("yes")
 
 def _fake_buck1_layer(name):
     # export a target of the same name to make td happy
@@ -125,18 +67,13 @@ def _fake_buck1_target(name):
         antlir_rule = "user-internal",
     )
 
-antlir2_enabled_packages = [
-    "metalos/imaging_initrd",
-    "metalos/initrd",
-]
-
 antlir2_shim = struct(
     fake_buck1_layer = _fake_buck1_layer,
     fake_buck1_feature = _fake_buck1_target,
     fake_buck1_target = _fake_buck1_target,
     fake_buck1_test = _fake_buck1_test,
-    should_make_parallel_feature = _should_make_parallel,
-    should_make_parallel_layer = _should_make_parallel,
-    should_make_parallel_test = _should_make_parallel,
-    should_make_parallel_package = partial(_should_make_parallel, enabled_packages = antlir2_enabled_packages),
+    should_shadow_feature = _should_shadow,
+    should_shadow_layer = _should_shadow,
+    should_shadow_test = _should_shadow,
+    should_shadow_package = _should_shadow,
 )

antlir/bzl/genrule/extractor/extract.bzl

@@ -151,7 +151,7 @@ cp "${{source_layer_path}}{output_dir}/feature.json" "$OUT"
         deps = ["//antlir/bzl/genrule/extractor:extract"],
     )
 
-    if antlir2_shim.should_make_parallel_feature(antlir2):
+    if antlir2_shim.should_shadow_feature(antlir2):
         if is_buck2():
             antlir2_feature.new(
                 name = name,

antlir/bzl/image/feature/new.bzl

@@ -384,7 +384,7 @@ def feature_new(
     # If we're on buck2, instantiate an antlir2 feature rule. This does not
     # conflict with the feature above, since antlir1 adds a "private" suffix to
     # all feature targets
-    if antlir2_shim.should_make_parallel_layer(antlir2):
+    if antlir2_shim.should_shadow_layer(antlir2):
         if is_buck2():
             antlir2_feature.new(
                 name,

antlir/bzl/image/package/new.bzl

@@ -55,7 +55,7 @@ def package_new(
     if format in _SENDSTREAM_FORMATS and not subvol_name:
         subvol_name = "volume"
 
-    if antlir2_shim.should_make_parallel_package(antlir2 = antlir2):
+    if antlir2_shim.should_shadow_package(antlir2 = antlir2):
         if is_buck2():
             antlir2_opts = shape.as_dict_shallow(loopback_opts) if loopback_opts else None
             opts_kwargs = {

antlir/bzl/image_cpp_unittest.bzl

@@ -85,7 +85,7 @@ def image_cpp_unittest(
         **wrapper_props.outer_test_kwargs
     )
 
-    if antlir2_shim.should_make_parallel_test(antlir2):
+    if antlir2_shim.should_shadow_test(antlir2):
         if is_buck2():
             antlir2_image_cpp_test(
                 name = name + ".antlir2",

antlir/bzl/image_genrule_layer.bzl

@@ -109,7 +109,7 @@ Optional arguments:
     - See the `_image_layer_impl` signature (in `image_layer_utils.bzl`)
         for supported, but less commonly used, kwargs.
     """
-    if antlir2_shim.should_make_parallel_layer(image_layer_kwargs.pop("antlir2", None), flavor = flavor):
+    if antlir2_shim.should_shadow_layer(image_layer_kwargs.pop("antlir2", None)):
         if is_buck2():
             antlir2_image.layer(
                 name = name + ".antlir2",

antlir/bzl/image_layer.bzl

@@ -143,7 +143,7 @@ def image_layer(
     [docs](/docs/tutorials/helper-buck-targets#imagelayer) for the list of
     possible helpers, their respective behaviours, and how to invoke them.
     """
-    if antlir2_shim.should_make_parallel_layer(image_layer_kwargs.pop("antlir2", None), flavor = flavor):
+    if antlir2_shim.should_shadow_layer(image_layer_kwargs.pop("antlir2", None)):
         if is_buck2():
             if not antlir2_allow_ignored_flavor_config_override and flavor_config_override:
                 fail("antlir2 does not support flavor_config_override: {}".format(flavor_config_override))

antlir/bzl/image_layer_alias.bzl

@@ -71,7 +71,7 @@ def image_layer_alias(name, layer, runtime = None, visibility = None, antlir2 =
 
     add_runtime_targets(name, runtime)
 
-    if antlir2_shim.should_make_parallel_layer(antlir2):
+    if antlir2_shim.should_shadow_layer(antlir2):
         if is_buck2():
             alias(
                 name = name + ".antlir2",

antlir/bzl/image_layer_from_package.bzl

@@ -33,7 +33,7 @@ def image_layer_from_package_helper(
         antlir2_src):
     flavor = flavor_to_struct(flavor)
     target = normalize_target(":" + name)
-    antlir2 = antlir2_shim.should_make_parallel_layer(image_layer_kwargs.pop("antlir2", None), flavor = flavor)
+    antlir2 = antlir2_shim.should_shadow_layer(image_layer_kwargs.pop("antlir2", None))
 
     # Do argument validation
     for bad_kwarg in ["parent_layer", "features"]:

antlir/bzl/image_python_unittest.bzl

@@ -136,7 +136,7 @@ def image_python_unittest(
         **wrapper_props.outer_test_kwargs
     )
 
-    if antlir2_shim.should_make_parallel_test(antlir2):
+    if antlir2_shim.should_shadow_test(antlir2):
         if is_buck2():
             antlir2_image_python_test(
                 name = name + ".antlir2",

antlir/bzl/image_rust_unittest.bzl

@@ -63,7 +63,7 @@ def image_rust_unittest(
         **wrapper_props.outer_test_kwargs
     )
 
-    if antlir2_shim.should_make_parallel_test(antlir2):
+    if antlir2_shim.should_shadow_test(antlir2):
         if is_buck2():
             antlir2_image_rust_test(
                 name = name + ".antlir2",