fix: Temporary directories are not removed (#109)

Author: khvn26

src/common/core/main.py

@@ -2,14 +2,15 @@
 import logging
 import os
 import sys
-import tempfile
 import typing
 
 from django.core.management import (
     execute_from_command_line as django_execute_from_command_line,
 )
+from environs import Env
 
 from common.core.cli import healthcheck
+from common.core.utils import TemporaryDirectory
 
 logger = logging.getLogger(__name__)
 
@@ -30,6 +31,7 @@ def ensure_cli_env() -> typing.Generator[None, None, None]:
         main()
     ```
     """
+    env = Env()
     ctx = contextlib.ExitStack()
 
     # TODO @khvn26 Move logging setup to here
@@ -43,9 +45,11 @@ def ensure_cli_env() -> typing.Generator[None, None, None]:
     os.environ.setdefault("DJANGO_SETTINGS_MODULE", "settings.dev")
 
     # Set up Prometheus' multiprocess mode
-    if "PROMETHEUS_MULTIPROC_DIR" not in os.environ:
-        prometheus_multiproc_dir_name = tempfile.mkdtemp()
-
+    if not env.str("PROMETHEUS_MULTIPROC_DIR", ""):
+        delete = not env.bool("PROMETHEUS_MULTIPROC_DIR_KEEP", False)
+        prometheus_multiproc_dir_name = ctx.enter_context(
+            TemporaryDirectory(delete=delete)
+        )
         logger.info(
             "Created %s for Prometheus multi-process mode",
             prometheus_multiproc_dir_name,

src/common/core/utils.py

@@ -2,9 +2,18 @@
 import logging
 import pathlib
 import random
+import sys
+import tempfile
 from functools import lru_cache
 from itertools import cycle
-from typing import Iterator, Literal, NotRequired, TypedDict, TypeVar, get_args
+from typing import (
+    Iterator,
+    Literal,
+    NotRequired,
+    TypedDict,
+    TypeVar,
+    get_args,
+)
 
 from django.conf import settings
 from django.contrib.auth import get_user_model
@@ -186,3 +195,40 @@ def using_database_replica(
         return manager
 
     return manager.db_manager(chosen_replica)
+
+
+if sys.version_info >= (3, 12):
+    # Already has the desired behavior; re-export for uniform imports.
+    TemporaryDirectory = tempfile.TemporaryDirectory
+else:
+    import contextlib
+    from typing import ContextManager, Generator
+
+    def TemporaryDirectory(
+        suffix: str | None = None,
+        prefix: str | None = None,
+        dir: str | None = None,
+        *,
+        delete: bool = True,
+    ) -> ContextManager[str]:
+        """
+        Create a temporary directory with optional cleanup control.
+
+        This wrapper exists because Python 3.12 changed TemporaryDirectory's behavior
+        by adding a 'delete' parameter, which doesn't exist in Python 3.11. This
+        function provides a consistent API across both versions.
+
+        When delete=True, uses the stdlib's TemporaryDirectory (auto-cleanup).
+        When delete=False, creates a directory with mkdtemp that persists after
+        the context manager exits, matching Python 3.12's delete=False behavior.
+
+        See https://docs.python.org/3.12/library/tempfile.html#tempfile.TemporaryDirectory for usage details.
+        """
+        if delete:
+            return tempfile.TemporaryDirectory(suffix, prefix, dir)
+
+        @contextlib.contextmanager
+        def _tmpdir() -> Generator[str, None, None]:
+            yield tempfile.mkdtemp(suffix, prefix, dir)
+
+        return _tmpdir()

tests/integration/core/test_main.py

@@ -1,6 +1,10 @@
+import os
+from pathlib import Path
+
 import django
 import pytest
 from django.core.management import ManagementUtility
+from pyfakefs.fake_filesystem import FakeFilesystem
 from pytest_httpserver import HTTPServer
 
 from common.core.main import main
@@ -104,3 +108,28 @@ def test_main__healthcheck_http__server_invalid_response__runs_expected(
     # When & Then
     with pytest.raises(Exception):
         main(argv)
+
+
+def test_main__prometheus_multiproc_remove_dir_on_exit_default__expected() -> None:
+    # Given
+    os.environ.pop("PROMETHEUS_MULTIPROC_DIR_KEEP", None)
+
+    # When
+    main(["flagsmith"])
+
+    # Then
+    assert not Path(os.environ["PROMETHEUS_MULTIPROC_DIR"]).exists()
+
+
+def test_main__prometheus_multiproc_remove_dir_on_exit_true__expected(
+    fs: FakeFilesystem,
+) -> None:
+    # Given
+    os.environ.pop("PROMETHEUS_MULTIPROC_DIR", None)
+    os.environ["PROMETHEUS_MULTIPROC_DIR_KEEP"] = "true"
+
+    # When
+    main(["flagsmith"])
+
+    # Then
+    assert Path(os.environ["PROMETHEUS_MULTIPROC_DIR"]).exists()