make platforms mandatory internally and configure them in the root MODULE

Author: aignas

CHANGELOG.md

@@ -104,6 +104,8 @@ END_UNRELEASED_TEMPLATE
   Set the `RULES_PYTHON_ENABLE_PIPSTAR=1` environment variable to enable it.
 * (utils) Add a way to run a REPL for any `rules_python` target that returns
   a `PyInfo` provider.
+* (pypi) Added early developer preview `pip.default` tag class in order to customize what
+  platforms are enabled. Only `rules_python` and root modules can use this feature.
 
 {#v0-0-0-removed}
 ### Removed

MODULE.bazel

@@ -65,40 +65,47 @@ _DEFAULT_OSX_PLATFORM_VERSION = "14.0"
 
 _DEFAULT_WINDOWS_PLATFORM_VERSION = "0"
 
-pip.default(
-    arch_name = "x86_64",
-    constraint_values = [
-        "@platforms//os:linux",
-        "@platforms//cpu:x86_64",
-    ],
-    env_platform_version = _DEFAULT_LINUX_PLATFORM_VERSION,
-    os_name = "linux",
-    platform = "linux_x86_64",
-)
-pip.default(
-    arch_name = "x86_64",
-    constraint_values = [
-        "@platforms//os:osx",
-        "@platforms//cpu:x86_64",
-    ],
-    # We choose the oldest non-EOL version at the time when we release `rules_python`.
-    # See https://endoflife.date/macos
-    env_platform_version = _DEFAULT_OSX_PLATFORM_VERSION,
-    os_name = "osx",
-    platform = "osx_x86_64",
-)
-pip.default(
-    arch_name = "aarch64",
-    constraint_values = [
-        "@platforms//os:osx",
-        "@platforms//cpu:aarch64",
-    ],
-    # We choose the oldest non-EOL version at the time when we release `rules_python`.
-    # See https://endoflife.date/macos
-    env_platform_version = _DEFAULT_OSX_PLATFORM_VERSION,
-    os_name = "osx",
-    platform = "osx_aarch64",
-)
+[
+    pip.default(
+        arch_name = cpu,
+        constraint_values = [
+            "@platforms//os:linux",
+            "@platforms//cpu:{}".format(cpu),
+        ],
+        env_platform_version = _DEFAULT_LINUX_PLATFORM_VERSION,
+        os_name = "linux",
+        platform = "linux_{}".format(cpu),
+    )
+    # TODO @aignas 2025-05-19: only leave tier 0-1 cpus when stabilizing the
+    # `pip.default` extension
+    for cpu in [
+        "aarch64",
+        "arm",
+        "ppc",
+        "s390x",
+        "x86_64",
+    ]
+]
+
+[
+    pip.default(
+        arch_name = cpu,
+        constraint_values = [
+            "@platforms//os:osx",
+            "@platforms//cpu:{}".format(cpu),
+        ],
+        # We choose the oldest non-EOL version at the time when we release `rules_python`.
+        # See https://endoflife.date/macos
+        env_platform_version = _DEFAULT_OSX_PLATFORM_VERSION,
+        os_name = "osx",
+        platform = "osx_{}".format(cpu),
+    )
+    for cpu in [
+        "aarch64",
+        "x86_64",
+    ]
+]
+
 pip.default(
     arch_name = "x86_64",
     constraint_values = [

python/private/pypi/extension.bzl

@@ -307,12 +307,6 @@ def _create_whl_repos(
         },
         extra_aliases = extra_aliases,
         whl_libraries = whl_libraries,
-        target_platforms = {
-            plat: None
-            for reqs in requirements_by_platform.values()
-            for req in reqs
-            for plat in req.target_platforms
-        },
     )
 
 def _whl_repos(*, requirement, whl_library_args, download_only, netrc, auth_patterns, multiple_requirements_for_whl = False, python_version, enable_pipstar = False):
@@ -545,7 +539,6 @@ You cannot use both the additive_build_content and additive_build_content_file a
     hub_group_map = {}
     exposed_packages = {}
     extra_aliases = {}
-    target_platforms = {}
     whl_libraries = {}
 
     for mod in module_ctx.modules:
@@ -629,7 +622,6 @@ You cannot use both the additive_build_content and additive_build_content_file a
             for whl_name, aliases in out.extra_aliases.items():
                 extra_aliases[hub_name].setdefault(whl_name, {}).update(aliases)
             exposed_packages.setdefault(hub_name, {}).update(out.exposed_packages)
-            target_platforms.setdefault(hub_name, {}).update(out.target_platforms)
             whl_libraries.update(out.whl_libraries)
 
             # TODO @aignas 2024-04-05: how do we support different requirement
@@ -667,10 +659,6 @@ You cannot use both the additive_build_content and additive_build_content_file a
             }
             for hub_name, extra_whl_aliases in extra_aliases.items()
         },
-        target_platforms = {
-            hub_name: sorted(p)
-            for hub_name, p in target_platforms.items()
-        },
         whl_libraries = {
             k: dict(sorted(args.items()))
             for k, args in sorted(whl_libraries.items())
@@ -762,14 +750,13 @@ def _pip_impl(module_ctx):
             },
             packages = mods.exposed_packages.get(hub_name, []),
             groups = mods.hub_group_map.get(hub_name),
-            target_platforms = mods.target_platforms.get(hub_name, []),
         )
 
     if bazel_features.external_deps.extension_metadata_has_reproducible:
         # NOTE @aignas 2025-04-15: this is set to be reproducible, because the
         # results after calling the PyPI index should be reproducible on each
         # machine.
-        return module_ctx.extension_metadata(reproducible = False)
+        return module_ctx.extension_metadata(reproducible = True)
     else:
         return None
 

python/private/pypi/hub_repository.bzl

@@ -87,10 +87,6 @@ The list of packages that will be exposed via all_*requirements macros. Defaults
             mandatory = True,
             doc = "The apparent name of the repo. This is needed because in bzlmod, the name attribute becomes the canonical name.",
         ),
-        "target_platforms": attr.string_list(
-            mandatory = True,
-            doc = "All of the target platforms for the hub repo",
-        ),
         "whl_map": attr.string_dict(
             mandatory = True,
             doc = """\

python/private/pypi/pip_repository.bzl

@@ -80,6 +80,16 @@ def _pip_repository_impl(rctx):
             requirements_osx = rctx.attr.requirements_darwin,
             requirements_windows = rctx.attr.requirements_windows,
             extra_pip_args = rctx.attr.extra_pip_args,
+            platforms = [
+                "linux_aarch64",
+                "linux_arm",
+                "linux_ppc",
+                "linux_s390x",
+                "linux_x86_64",
+                "osx_aarch64",
+                "osx_x86_64",
+                "windows_x86_64",
+            ],
         ),
         extra_pip_args = rctx.attr.extra_pip_args,
         evaluate_markers = lambda rctx, requirements: evaluate_markers_py(

python/private/pypi/requirements_files_by_platform.bzl

@@ -16,19 +16,6 @@
 
 load(":whl_target_platforms.bzl", "whl_target_platforms")
 
-# TODO @aignas 2024-05-13: consider using the same platform tags as are used in
-# the //python:versions.bzl
-DEFAULT_PLATFORMS = [
-    "linux_aarch64",
-    "linux_arm",
-    "linux_ppc",
-    "linux_s390x",
-    "linux_x86_64",
-    "osx_aarch64",
-    "osx_x86_64",
-    "windows_x86_64",
-]
-
 def _default_platforms_from(*, filter, python_version, choose_from):
     if not filter:
         fail("Must specific a filter string, got: {}".format(filter))
@@ -149,7 +136,7 @@ def requirements_files_by_platform(
     _default_platforms = lambda f: _default_platforms_from(
         filter = f,
         python_version = python_version,
-        choose_from = platforms or DEFAULT_PLATFORMS,
+        choose_from = platforms,
     )
 
     platforms_from_args = _platforms_from_args(extra_pip_args)

tests/pypi/requirements_files_by_platform/requirements_files_by_platform_tests.bzl

@@ -15,10 +15,27 @@
 ""
 
 load("@rules_testing//lib:test_suite.bzl", "test_suite")
-load("//python/private/pypi:requirements_files_by_platform.bzl", "requirements_files_by_platform")  # buildifier: disable=bzl-visibility
+load("//python/private/pypi:requirements_files_by_platform.bzl", _sut = "requirements_files_by_platform")  # buildifier: disable=bzl-visibility
 
 _tests = []
 
+requirements_files_by_platform = lambda **kwargs: _sut(
+    platforms = kwargs.pop(
+        "platforms",
+        [
+            "linux_aarch64",
+            "linux_arm",
+            "linux_ppc",
+            "linux_s390x",
+            "linux_x86_64",
+            "osx_aarch64",
+            "osx_x86_64",
+            "windows_x86_64",
+        ],
+    ),
+    **kwargs
+)
+
 def _test_fail_no_requirements(env):
     errors = []
     requirements_files_by_platform(