[antlir2][buck] add constraints for rou

Summary:
Instead of just the OS version, we also have ROU internally that updates those
OS versions in a rolling manner. Apply the same treatment to ROU.

Test Plan:
```
❯ buck2 test fbcode//antlir/antlir2/test_images/cfg/os:
Buck UI: https://www.internalfb.com/buck2/5895be5d-f4c9-4c3d-9158-c556ba9199ed
Test UI: https://www.internalfb.com/intern/testinfra/testrun/12666373954568127
Tests finished: Pass 48. Fail 0. Fatal 0. Skip 0. Build failure 0

❯ buck test fbcode//antlir/antlir2/test_images/cfg/facebook/rou:unittest-{centos{8,9},eln}
❯ buck2 test fbcode//antlir/antlir2/test_images/cfg/facebook/rou:unittest-centos8 fbcode//antlir/antlir2/test_images/cfg/facebook/rou:unittest-centos9 fbcode//antlir/antlir2/test_images/cfg/facebook/rou:unittest-eln
Buck UI: https://www.internalfb.com/buck2/5da69383-97f4-43ce-95cb-0853f2e8e4e8
Test UI: https://www.internalfb.com/intern/testinfra/testrun/9570149216939393
Jobs completed: 18. Time elapsed: 2.1s.
Tests finished: Pass 3. Fail 0. Fatal 0. Skip 0. Build failure 0
```

Reviewed By: epilatow

Differential Revision: D49350914

fbshipit-source-id: a189492caa58c35b4f45a1790ac19fa6234cfc14

antlir/antlir2/bzl/compat.bzl

@@ -51,7 +51,20 @@ def _flavor_config_override_to_versionlock_extend(flavor_config_override):
             )
     return versionlock_extend
 
+def _default_rou_from_antlir1_flavor(flavor: str | typing.Any) -> str:
+    if not types.is_string(flavor):
+        flavor = flavor.unaliased_name
+    parts = flavor.split("-")
+    if len(parts) >= 2:
+        if parts[-2] == "rou":
+            phase = parts[-1]
+            if phase == "testing" or phase == "untested":
+                return "test"
+            return phase
+    return "stable"
+
 compat = struct(
     from_antlir1_flavor = _from_antlir1_flavor,
     flavor_config_override_to_versionlock_extend = _flavor_config_override_to_versionlock_extend,
+    default_rou_from_antlir1_flavor = _default_rou_from_antlir1_flavor,
 )

antlir/antlir2/bzl/configured_alias.bzl

@@ -4,7 +4,7 @@
 # LICENSE file in the root directory of this source tree.
 
 load("//antlir/antlir2/bzl:platform.bzl", "rule_with_default_target_platform")
-load("//antlir/antlir2/bzl/image/facebook:fb_cfg.bzl", "fbcode_platform_refs", "transition_fbcode_platform")
+# @oss-disable
 load("//antlir/antlir2/os:cfg.bzl", "os_transition", "os_transition_refs")
 load("//antlir/bzl:build_defs.bzl", "is_facebook")
 
@@ -14,8 +14,6 @@ def _transition_impl(platform: PlatformInfo, refs: struct, attrs: struct) -> Pla
     if attrs.target_arch:
         target_arch = getattr(refs, "arch." + attrs.target_arch)[ConstraintValueInfo]
         constraints[target_arch.setting.label] = target_arch
-        if is_facebook:
-            constraints = transition_fbcode_platform(refs, attrs, constraints)
 
     constraints = os_transition(
         default_os = attrs.default_os,
@@ -24,6 +22,9 @@ def _transition_impl(platform: PlatformInfo, refs: struct, attrs: struct) -> Pla
         overwrite = True,
     )
 
+    if is_facebook:
+        constraints = fb_transition(refs, attrs, constraints)
+
     return PlatformInfo(
         label = platform.label,
         configuration = ConfigurationInfo(
@@ -41,7 +42,10 @@ _transition = transition(
         # @oss-disable
         # @oss-enable {}
     ) | os_transition_refs(),
-    attrs = ["default_os", "target_arch"],
+    attrs = ["default_os", "target_arch"] + (
+        # @oss-disable
+        [] # @oss-enable
+    ),
 )
 
 def _configured_alias_impl(ctx: AnalysisContext) -> list[Provider]:
@@ -57,7 +61,10 @@ _configured_alias = rule(
             default = None,
             doc = "Build for a specific target arch without using `buck -c`",
         ),
-    },
+    } | (
+        # @oss-disable
+        # @oss-enable {}
+    ),
 )
 
 antlir2_configured_alias = rule_with_default_target_platform(_configured_alias)

antlir/antlir2/bzl/image/cfg.bzl

@@ -12,7 +12,7 @@ Currently this supports reconfiguring the target cpu architecture.
 """
 
 load("//antlir/antlir2/bzl:types.bzl", "FlavorInfo")
-load("//antlir/antlir2/bzl/image/facebook:fb_cfg.bzl", "fbcode_platform_refs", "transition_fbcode_platform")
+# @oss-disable
 load("//antlir/antlir2/os:cfg.bzl", "os_transition", "os_transition_refs", "remove_os_constraints")
 load("//antlir/bzl:build_defs.bzl", "is_facebook")
 
@@ -30,17 +30,35 @@ def cfg_attrs():
             default = None,
             doc = "Build this image for a specific target arch without using `buck -c`",
         ),
-    }
+    } | (
+        # @oss-disable
+        # @oss-enable {}
+    )
 
 def attrs_selected_by_cfg():
     return {
         # only attrs.option because it cannot be set on build appliance layers
         "flavor": attrs.option(
             attrs.dep(providers = [FlavorInfo]),
             default = select({
-                "//antlir/antlir2/os:centos8": "//antlir/antlir2/facebook/flavor/centos8:centos8",
-                "//antlir/antlir2/os:centos9": "//antlir/antlir2/facebook/flavor/centos9:centos9",
-                "//antlir/antlir2/os:eln": "//antlir/antlir2/facebook/flavor/eln:eln",
+                "//antlir/antlir2/os:centos8": select({
+                    "//antlir/antlir2/os/facebook:rou-preparation": "//antlir/antlir2/facebook/flavor/centos8-rou-preparation:centos8-rou-preparation",
+                    "//antlir/antlir2/os/facebook:rou-rolling": "//antlir/antlir2/facebook/flavor/centos8-rou-rolling:centos8-rou-rolling",
+                    "//antlir/antlir2/os/facebook:rou-stable": "//antlir/antlir2/facebook/flavor/centos8:centos8",
+                    "//antlir/antlir2/os/facebook:rou-test": "//antlir/antlir2/facebook/flavor/centos8-rou-untested:centos8-rou-untested",
+                }),
+                "//antlir/antlir2/os:centos9": select({
+                    "//antlir/antlir2/os/facebook:rou-preparation": "//antlir/antlir2/facebook/flavor/centos9-rou-preparation:centos9-rou-preparation",
+                    "//antlir/antlir2/os/facebook:rou-rolling": "//antlir/antlir2/facebook/flavor/centos9-rou-rolling:centos9-rou-rolling",
+                    "//antlir/antlir2/os/facebook:rou-stable": "//antlir/antlir2/facebook/flavor/centos9:centos9",
+                    "//antlir/antlir2/os/facebook:rou-test": "//antlir/antlir2/facebook/flavor/centos9-rou-untested:centos9-rou-untested",
+                }),
+                "//antlir/antlir2/os:eln": select({
+                    "//antlir/antlir2/os/facebook:rou-preparation": "//antlir/antlir2/facebook/flavor/eln-rou-preparation:eln-rou-preparation",
+                    "//antlir/antlir2/os/facebook:rou-rolling": "//antlir/antlir2/facebook/flavor/eln-rou-rolling:eln-rou-rolling",
+                    "//antlir/antlir2/os/facebook:rou-stable": "//antlir/antlir2/facebook/flavor/eln:eln",
+                    "//antlir/antlir2/os/facebook:rou-test": "//antlir/antlir2/facebook/flavor/eln-rou-untested:eln-rou-untested",
+                }),
                 "//antlir/antlir2/os:none": "//antlir/antlir2/flavor:none",
                 # TODO: in D49383768 this will be disallowed so that we can
                 # guarantee that we'll never end up building a layer without
@@ -56,8 +74,6 @@ def _impl(platform: PlatformInfo, refs: struct, attrs: struct) -> PlatformInfo:
     if attrs.target_arch:
         target_arch = getattr(refs, "arch." + attrs.target_arch)[ConstraintValueInfo]
         constraints[target_arch.setting.label] = target_arch
-        if is_facebook:
-            constraints = transition_fbcode_platform(refs, attrs, constraints)
 
     if attrs.default_os:
         # The rule transition to set the default antlir2 OS only happens if the
@@ -83,6 +99,9 @@ def _impl(platform: PlatformInfo, refs: struct, attrs: struct) -> PlatformInfo:
     if attrs.antlir_internal_build_appliance:
         constraints = remove_os_constraints(refs = refs, constraints = constraints)
 
+    if is_facebook:
+        constraints = fb_transition(refs, attrs, constraints)
+
     label = platform.label
 
     # if we made any changes, change the label
@@ -134,5 +153,6 @@ remove_os_constraint = transition(
         "os_constraint": "//antlir/antlir2/os:os",
         "os_family_constraint": "//antlir/antlir2/os/family:family",
         "package_manager_constraint": "//antlir/antlir2/os/package_manager:package_manager",
+        # @oss-disable
     },
 )

antlir/antlir2/bzl/image/layer.bzl

@@ -541,6 +541,7 @@ def layer(
         default_os: str | None = None,
         # TODO: remove this flag when all images are using this new mechanism
         use_default_os_from_package: bool | None = None,
+        default_rou: str | None = None,
         # We'll implicitly forward some users to antlir2, so any hacks for them
         # should be confined behind this flag
         implicit_antlir2: bool = False,
@@ -554,6 +555,8 @@ def layer(
     if implicit_antlir2:
         flavor = kwargs.pop("flavor", None)
         kwargs["flavor"] = compat.from_antlir1_flavor(flavor) if flavor else None
+        if is_facebook:
+            default_rou = compat.default_rou_from_antlir1_flavor(flavor) if flavor else None
 
     if use_default_os_from_package == None:
         use_default_os_from_package = should_all_images_in_package_use_default_os()
@@ -563,6 +566,8 @@ def layer(
     # TODO(vmagro): codemod existing callsites to use default_os directly
     if "flavor" in kwargs and default_os:
         fail("default_os= is preferred, stop setting flavor=")
+    if kwargs.get("flavor", None) and not default_rou:
+        default_rou = compat.default_rou_from_antlir1_flavor(kwargs["flavor"])
 
     kwargs.update({"_feature_" + key: val for key, val in feature_attrs(features).items()})
     compatible_with = kwargs.pop("compatible_with", []) or []
@@ -596,6 +601,7 @@ def layer(
     return layer_rule(
         name = name,
         default_os = default_os,
+        default_rou = default_rou,
         visibility = get_visibility(visibility),
         _implicit_image_test = "//antlir/antlir2/testing/implicit_image_test:implicit_image_test",
         **kwargs

antlir/antlir2/bzl/package/btrfs.bzl

@@ -5,7 +5,7 @@
 
 load("//antlir/antlir2/bzl:platform.bzl", "rule_with_default_target_platform")
 load("//antlir/antlir2/bzl:types.bzl", "LayerInfo")
-load("//antlir/antlir2/bzl/package:cfg.bzl", "package_cfg")
+load("//antlir/antlir2/bzl/package:cfg.bzl", "cfg_attrs", "package_cfg")
 load(":gpt.bzl", "GptPartitionSource")
 load(":sendstream.bzl", "anon_v1_sendstream")
 
@@ -83,9 +83,7 @@ _btrfs = rule(
             ),
             default = None,
         ),
-        # used by transition
-        "target_arch": attrs.option(attrs.string(), default = None),
-    },
+    } | cfg_attrs(),
     cfg = package_cfg,
 )
 

antlir/antlir2/bzl/package/cfg.bzl

@@ -4,11 +4,13 @@
 # LICENSE file in the root directory of this source tree.
 
 load("//antlir/antlir2/bzl:types.bzl", "LayerInfo")
-load("//antlir/antlir2/bzl/image:cfg.bzl", "cfg_attrs")
+load("//antlir/antlir2/bzl/image:cfg.bzl", _cfg_attrs = "cfg_attrs")
 # @oss-disable
 load("//antlir/antlir2/os:cfg.bzl", "os_transition", "os_transition_refs")
 load("//antlir/bzl:build_defs.bzl", "is_facebook")
 
+cfg_attrs = _cfg_attrs
+
 # Let the layer be configured by the same configuration attrs in image.layer
 layer_attrs = {
     "layer": attrs.dep(providers = [LayerInfo]),
@@ -20,8 +22,6 @@ def _package_cfg_impl(platform: PlatformInfo, refs: struct, attrs: struct) -> Pl
     if attrs.target_arch:
         target_arch = getattr(refs, "arch." + attrs.target_arch)[ConstraintValueInfo]
         constraints[target_arch.setting.label] = target_arch
-        if is_facebook:
-            constraints = transition_fbcode_platform(refs, attrs, constraints)
 
     if attrs.default_os:
         constraints = os_transition(
@@ -33,6 +33,9 @@ def _package_cfg_impl(platform: PlatformInfo, refs: struct, attrs: struct) -> Pl
             overwrite = True,
         )
 
+    if is_facebook:
+        constraints = fb_transition(refs, attrs, constraints)
+
     label = platform.label
 
     # if we made any changes, change the label

antlir/antlir2/os/cfg.bzl

@@ -3,6 +3,7 @@
 # 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:build_defs.bzl", "is_facebook")
 load(":defs.bzl", "OsVersionInfo")
 
 _OS_REFS = {
@@ -39,4 +40,6 @@ def remove_os_constraints(*, constraints, refs):
     constraints.pop(refs.os_constraint[ConstraintSettingInfo].label, None)
     constraints.pop(refs.os_family_constraint[ConstraintSettingInfo].label, None)
     constraints.pop(refs.package_manager_constraint[ConstraintSettingInfo].label, None)
+    if is_facebook:
+        constraints.pop(refs.rou_constraint[ConstraintSettingInfo].label, None)
     return constraints

antlir/antlir2/test_images/cfg/os/BUCK

@@ -2,12 +2,20 @@ load("//antlir/antlir2/bzl/feature:defs.bzl", "feature")
 load("//antlir/antlir2/bzl/image:defs.bzl", "image")
 load("//antlir/antlir2/bzl/package:defs.bzl", "package")
 load("//antlir/antlir2/testing:image_test.bzl", "image_rust_test")
+load("//antlir/bzl:build_defs.bzl", "is_facebook")
 load("//antlir/rpm/dnf2buck:repo.bzl", "repo")
 load("//antlir/rpm/dnf2buck:rpm.bzl", "rpm")
 load(":defs.bzl", "write_os")
 
 oncall("antlir")
 
+# This single-constraint select is useful to ensure that we can select on an ROU
+# and that the default of stable is actually configured and we don't need to
+# rely on DEFAULT
+test_rpm_root = select({
+    "//antlir/antlir2/os/facebook:rou-stable": "test-rpm-root",
+}) if is_facebook else "test-rpm-root"
+
 image.layer(
     name = "root",
     dnf_additional_repos = [":repo"],
@@ -21,7 +29,7 @@ image.layer(
             "coreutils",
             "rpm",
             # @oss-disable
-            "test-rpm-root",
+            test_rpm_root,
         ]),
         write_os("/root.os"),
     ],