Fix reproducibility of prepared provider packages (fix flit frontend)

After some checks it turned out that reproducibility of produced
packages depends not only on the build backend configured for the
project but also on the build front-end used - because frontend is
the one to modify meta-data in prepared packages - including the build
tool used, it's version and metadata version supported by the front-end.

That's why in order to maintain reproducibility for anyone who builds
the packages, we have to pin not only the build backend in
pyproject.toml (flit-core) but also build fronted used (flit).

Since package preparation is done with breeze, we can do it by
pinning flit (and just in case also flit-core) so that anyone who
builds specific version of the package will use exactly the same flit
as the person who built the original packages.

This way we will avoid reproducibility problems experienced with 1.5.0
release of FAB.

dev/README_RELEASE_PROVIDER_PACKAGES.md

@@ -349,7 +349,6 @@ export AIRFLOW_REPO_ROOT=$(pwd -P)
 rm -rf ${AIRFLOW_REPO_ROOT}/dist/*
 ```
 
-
 * Release candidate packages:
 
 ```shell script

dev/breeze/README.md

@@ -136,6 +136,6 @@ PLEASE DO NOT MODIFY THE HASH BELOW! IT IS AUTOMATICALLY UPDATED BY PRE-COMMIT.
 
 ---------------------------------------------------------------------------------------------------------
 
-Package config hash: f13c42703e0a262d9f3c1bee608ff32c368be4c6a11f150a2f95809938641f5ec07904d5cc2e3944dfe4d206dc52846f8b81193fc279a333ff898dd033e07be4
+Package config hash: 5d32e2c150de1cc22d522f94d86500c739f434439ae064e35791ac795932a1f21509c3d0fcf9f2351e7901a32601190bd4cb640799620a44d0ff6d9244aef57c
 
 ---------------------------------------------------------------------------------------------------------

dev/breeze/pyproject.toml

@@ -47,7 +47,20 @@ dependencies = [
     "black>=23.11.0",
     "click>=8.1.7",
     "filelock>=3.13.0",
-    "flit>=3.5.0",
+    #
+    # We pin flit in order to make sure reproducibility of provider packages is maintained
+    # It turns out that when packages are prepared metadata version in the produced packages
+    # is taken from the front-end not from the backend, so in order to make sure that the
+    # packages are reproducible, we should pin both backend in "build-system" and frontend in
+    # "dependencies" of the environment that is used to build the packages.
+    #
+    # TODO(potiuk): automate bumping the version of flit in breeze and sync it with
+    # the version in the template for provider packages with pre-commit also add instructions in
+    # the source packages explaining that reproducibility can only be achieved by using the same
+    # version of flit front-end to build the package
+    #
+    "flit==3.10.1",
+    "flit-core==3.10.1",
     "google-api-python-client>=2.142.0",
     "google-auth-httplib2>=0.2.0",
     "google-auth-oauthlib>=1.2.0",

dev/breeze/src/airflow_breeze/commands/release_candidate_command.py

@@ -27,7 +27,6 @@
 from airflow_breeze.utils.confirm import confirm_action
 from airflow_breeze.utils.console import console_print
 from airflow_breeze.utils.path_utils import AIRFLOW_SOURCES_ROOT, DIST_DIR, OUT_DIR
-from airflow_breeze.utils.python_versions import check_python_version
 from airflow_breeze.utils.reproducible import get_source_date_epoch, repack_deterministically
 from airflow_breeze.utils.run_utils import run_command
 
@@ -341,7 +340,6 @@ def remove_old_releases(version, repo_root):
     "--version", required=True, help="The release candidate version e.g. 2.4.3rc1", envvar="VERSION"
 )
 def prepare_airflow_tarball(version: str):
-    check_python_version()
     from packaging.version import Version
 
     airflow_version = Version(version)
@@ -367,7 +365,6 @@ def prepare_airflow_tarball(version: str):
 )
 @option_answer
 def publish_release_candidate(version, previous_version, github_token):
-    check_python_version()
     from packaging.version import Version
 
     airflow_version = Version(version)

dev/breeze/src/airflow_breeze/commands/release_management_commands.py

@@ -151,7 +151,7 @@
     generate_providers_metadata_for_package,
     get_related_providers,
 )
-from airflow_breeze.utils.python_versions import check_python_version, get_python_version_list
+from airflow_breeze.utils.python_versions import get_python_version_list
 from airflow_breeze.utils.reproducible import get_source_date_epoch, repack_deterministically
 from airflow_breeze.utils.run_utils import (
     run_command,
@@ -530,7 +530,6 @@ def prepare_airflow_packages(
     version_suffix_for_pypi: str,
     use_local_hatch: bool,
 ):
-    check_python_version()
     perform_environment_checks()
     fix_ownership_using_docker()
     cleanup_python_generated_files()
@@ -576,7 +575,6 @@ def prepare_airflow_task_sdk_packages(
     package_format: str,
     use_local_hatch: bool,
 ):
-    check_python_version()
     perform_environment_checks()
     fix_ownership_using_docker()
     cleanup_python_generated_files()
@@ -907,7 +905,6 @@ def prepare_provider_packages(
     skip_tag_check: bool,
     version_suffix_for_pypi: str,
 ):
-    check_python_version(release_provider_packages=True)
     perform_environment_checks()
     fix_ownership_using_docker()
     cleanup_python_generated_files()
@@ -3182,7 +3179,6 @@ def prepare_helm_chart_tarball(
 ) -> None:
     import yaml
 
-    check_python_version()
     chart_yaml_file_content = CHART_YAML_FILE.read_text()
     chart_yaml_dict = yaml.safe_load(chart_yaml_file_content)
     version_in_chart = chart_yaml_dict["version"]
@@ -3324,8 +3320,6 @@ def prepare_helm_chart_tarball(
 @option_dry_run
 @option_verbose
 def prepare_helm_chart_package(sign_email: str):
-    check_python_version()
-
     import yaml
 
     from airflow_breeze.utils.kubernetes_utils import (

dev/breeze/src/airflow_breeze/templates/pyproject_TEMPLATE.toml.jinja2

@@ -39,9 +39,8 @@
 
 # IF YOU WANT TO MODIFY THIS FILE, YOU SHOULD MODIFY THE TEMPLATE
 # `pyproject_TEMPLATE.toml.jinja2` IN the `dev/breeze/src/airflow_breeze/templates` DIRECTORY
-#
 [build-system]
-requires = ["flit_core==3.10.0"]
+requires = ["flit_core==3.10.1"]
 build-backend = "flit_core.buildapi"
 
 [project]

dev/breeze/src/airflow_breeze/utils/python_versions.py

@@ -43,17 +43,3 @@ def get_python_version_list(python_versions: str) -> list[str]:
         )
         sys.exit(1)
     return python_version_list
-
-
-def check_python_version(release_provider_packages: bool = False):
-    if not sys.version_info < (3, 12) and release_provider_packages:
-        get_console().print("[error]Python 3.12 is not supported.\n")
-        get_console().print(
-            "[warning]Please reinstall Breeze using Python 3.9 - 3.11 environment because not all "
-            "provider packages support Python 3.12 yet.[/]\n\n"
-            "If you are using uv:\n\n"
-            "   uv tool install --force --reinstall --python 3.9 -e ./dev/breeze\n\n"
-            "If you are using pipx:\n\n"
-            "   pipx install --python $(which python3.9) --force -e ./dev/breeze\n"
-        )
-        sys.exit(1)

dev/breeze/src/airflow_breeze/utils/reproducible.py

@@ -43,7 +43,6 @@
 from subprocess import CalledProcessError, CompletedProcess
 
 from airflow_breeze.utils.path_utils import AIRFLOW_SOURCES_ROOT, OUT_DIR, REPRODUCIBLE_DIR
-from airflow_breeze.utils.python_versions import check_python_version
 from airflow_breeze.utils.run_utils import run_command
 
 
@@ -91,7 +90,6 @@ def reset(tarinfo):
         tarinfo.mtime = timestamp
         return tarinfo
 
-    check_python_version()
     OUT_DIR.mkdir(exist_ok=True)
     shutil.rmtree(REPRODUCIBLE_DIR, ignore_errors=True)
     REPRODUCIBLE_DIR.mkdir(exist_ok=True)
@@ -149,7 +147,6 @@ def reset(tarinfo):
 
 
 def main():
-    check_python_version()
     parser = ArgumentParser()
     parser.add_argument("-a", "--archive", help="archive to repack")
     parser.add_argument("-o", "--out", help="archive destination")