packaging: deletion window machinery

This adds `in_deletion_window` to the File, Release, and Project
models. The three models currently compose in deletion semantics
as follows:

1. A file is deletable iff it was uploaded within the last 7 days
2. A release is deletable iff all of its files are deletable
3. A project is deletable iff all of its releases are deletable

This results in no special casing: the deletability of
releases and projects is entirely "driven" by the deletability
of files, as files are the primary way in which users drive the
creation of releases and projects.

This PR does **not** connect the deletion semantics to actual
UI or view changes; I'll do that in a follow-up, to keep the
patches small.

Signed-off-by: William Woodruff <[email protected]>

tests/unit/packaging/test_models.py

@@ -11,7 +11,9 @@
 # limitations under the License.
 
 from collections import OrderedDict
+from datetime import datetime, timedelta
 
+import freezegun
 import pretend
 import pytest
 
@@ -479,6 +481,47 @@ def test_deletion_macaroon_with_macaroon_warning(
             == 0
         )
 
+    def test_in_deletion_window(self, db_session):
+        project = DBProjectFactory.create()
+
+        # Empty project, trivially deletable.
+        assert project.in_deletion_window
+
+        fake_now = datetime(year=2000, month=1, day=1)
+
+        # Releases are all deletable, so the project is deletable.
+        release1 = DBReleaseFactory.create(project=project)
+        DBFileFactory.create(
+            release=release1, upload_time=fake_now, packagetype="bdist_wheel"
+        )
+        DBFileFactory.create(
+            release=release1,
+            upload_time=fake_now - timedelta(hours=1),
+            packagetype="bdist_wheel",
+        )
+
+        release2 = DBReleaseFactory.create(project=project)
+        DBFileFactory.create(
+            release=release2,
+            upload_time=fake_now - timedelta(days=2),
+            packagetype="bdist_wheel",
+        )
+        DBFileFactory.create(
+            release=release2,
+            upload_time=fake_now - timedelta(days=3),
+            packagetype="bdist_wheel",
+        )
+
+        with freezegun.freeze_time(fake_now):
+            assert project.in_deletion_window
+
+        # One release is not deletable, so the entire project is not deletable.
+        release3 = DBReleaseFactory.create(project=project)
+        DBFileFactory.create(release=release3, upload_time=fake_now - timedelta(days=8))
+        with freezegun.freeze_time(fake_now):
+            assert not release3.in_deletion_window
+            assert not project.in_deletion_window
+
 
 class TestDependency:
     def test_repr(self, db_session):
@@ -1087,6 +1130,43 @@ def test_description_relationship(self, db_request):
         assert release in db_request.db.deleted
         assert description in db_request.db.deleted
 
+    def test_in_deletion_window(self, db_session):
+        project = DBProjectFactory.create()
+        release = DBReleaseFactory.create(project=project)
+
+        # No files, trivially deletable.
+        assert release.in_deletion_window
+
+        fake_now = datetime(year=2000, month=1, day=1)
+
+        DBFileFactory.create(
+            release=release, upload_time=fake_now, packagetype="bdist_wheel"
+        )
+        DBFileFactory.create(
+            release=release,
+            upload_time=fake_now - timedelta(hours=1),
+            packagetype="bdist_wheel",
+        )
+        DBFileFactory.create(
+            release=release,
+            upload_time=fake_now - timedelta(days=1, hours=1),
+            packagetype="bdist_wheel",
+        )
+
+        with freezegun.freeze_time(fake_now):
+            # All files are deletable, so release is deletable.
+            assert release.in_deletion_window
+
+        DBFileFactory.create(
+            release=release,
+            upload_time=fake_now - timedelta(days=7, hours=1),
+            packagetype="bdist_wheel",
+        )
+
+        with freezegun.freeze_time(fake_now):
+            # One file is not deletable, so the entire release is not deletable.
+            assert not release.in_deletion_window
+
 
 class TestFile:
     def test_requires_python(self, db_session):
@@ -1215,3 +1295,31 @@ def test_pretty_wheel_tags(self, db_session):
         )
 
         assert rfile.pretty_wheel_tags == ["Source"]
+
+    @pytest.mark.parametrize(
+        ("upload_time", "deletable"),
+        [
+            # Deletable at the instant of upload
+            (datetime(year=2000, month=1, day=1), True),
+            # Deletable within the normal period
+            (datetime(year=2000, month=1, day=1) - timedelta(hours=1), True),
+            (datetime(year=2000, month=1, day=1) - timedelta(days=1), True),
+            (datetime(year=2000, month=1, day=1) - timedelta(days=5), True),
+            # Deletable at the instant of the end of the deletion period
+            (datetime(year=2000, month=1, day=1) - timedelta(days=7), True),
+            # Deletable when inexplicably uploaded in the future
+            (datetime(year=2000, month=1, day=1) + timedelta(hours=1), True),
+            # Not deletable outside of the deletion period
+            (datetime(year=2000, month=1, day=1) - timedelta(days=7, seconds=1), False),
+            (datetime(year=2000, month=1, day=1) - timedelta(days=8), False),
+        ],
+    )
+    def test_in_deletion_window(self, db_session, upload_time, deletable):
+        project = DBProjectFactory.create()
+        release = DBReleaseFactory.create(project=project)
+
+        fake_now = datetime(year=2000, month=1, day=1)
+
+        with freezegun.freeze_time(fake_now):
+            file = DBFileFactory.create(release=release, upload_time=upload_time)
+            assert file.in_deletion_window == deletable

warehouse/packaging/models.py

@@ -15,6 +15,7 @@
 import typing
 
 from collections import OrderedDict
+from datetime import datetime, timedelta
 from uuid import UUID
 
 import packaging.utils
@@ -459,6 +460,17 @@ def latest_version(self):
             .first()
         )
 
+    @property
+    def in_deletion_window(self) -> bool:
+        """
+        A project can be deleted by a non-admin owner if it's within its
+        "deletion window," i.e. each of its releases and constituent files
+        are within their respective deletion windows.
+
+        See `Release.in_deletion_window`.
+        """
+        return all(release.in_deletion_window for release in self.releases)
+
 
 class DependencyKind(enum.IntEnum):
     requires = 1
@@ -812,6 +824,18 @@ def trusted_published(self) -> bool:
             return False
         return all(file.uploaded_via_trusted_publisher for file in files)
 
+    @property
+    def in_deletion_window(self) -> bool:
+        """
+        A release can be deleted by a non-admin owner if its within its
+        "deletion window," i.e. each of its files is within its respective
+        deletion window.
+
+        See `File.in_deletion_window`.
+        """
+        files = self.files.all()  # type: ignore[attr-defined]
+        return all(file.in_deletion_window for file in files)
+
 
 class PackageType(str, enum.Enum):
     bdist_dmg = "bdist_dmg"
@@ -924,6 +948,14 @@ def validates_requires_python(self, *args, **kwargs):
     def pretty_wheel_tags(self) -> list[str]:
         return wheel.filename_to_pretty_tags(self.filename)
 
+    @property
+    def in_deletion_window(self) -> bool:
+        """
+        A file can be deleted by a non-admin owner if it's within its
+        "deletion window," i.e. was uploaded no more than 7 days ago.
+        """
+        return self.upload_time >= datetime.now() - timedelta(days=7)
+
 
 class Filename(db.ModelBase):
     __tablename__ = "file_registry"