Added get_export_filename()

Author: rgaudin

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [1.1.0] - 2024-01-30
 
+### Added
+
+- `get_export_filename(image, platform)` for an fs-safe filename
+
 ### Changed
 
 - `fs_name` now includes image reference and is filesystem safe for all OS.

src/docker_export/__init__.py

@@ -373,6 +373,11 @@ def headers(self) -> dict[str, str]:
         return {"Authorization": f"Bearer {self.token}"}
 
 
+def get_export_filename(image: Image, platform: Platform) -> str:
+    """Filesystem-safe filename to export an image for a platform"""
+    return sanitize_filename(f"{image.fs_name}_{platform}.tar")
+
+
 def get_manifests(image: Image, auth: RegistryAuth):
     """get list of fat-manifests for the image"""
     resp = requests.get(
@@ -906,7 +911,7 @@ def main():
         image = Image.parse(**args)
         dest = pathlib.Path(output).expanduser().resolve()
         if not dest.suffix == ".tar":
-            dest = dest.joinpath(sanitize_filename(f"{image.fs_name}_{platform}.tar"))
+            dest = dest.joinpath(get_export_filename(image=image, platform=platform))
         build_dir = (
             pathlib.Path(build_dir).expanduser().resolve() if build_dir else None
         )

tests/test_export.py

@@ -7,7 +7,7 @@
 import py  # pyright: ignore [reportMissingTypeStubs]
 import pytest
 
-from docker_export import Image, Platform, export
+from docker_export import Image, Platform, export, get_export_filename
 
 
 @pytest.fixture(scope="session")
@@ -22,7 +22,7 @@ def platform_name() -> str:
 
 @pytest.fixture(scope="session")
 def expected_filepath() -> pathlib.Path:
-    return pathlib.Path("ghcr.io_offspot_base-httpd.tar")
+    return pathlib.Path("ghcr.io_offspot_base-httpd_1.0_linuxarm64.tar")
 
 
 @pytest.fixture(scope="session")
@@ -42,7 +42,9 @@ def test_export(
     export(
         image=Image.parse(image_name),
         platform=Platform.parse(platform_name),
-        to=expected_filepath,
+        to=pathlib.Path(
+            get_export_filename(Image.parse(image_name), Platform.parse(platform_name))
+        ),
     )
     assert expected_filepath.exists()
     assert expected_filepath.stat().st_size == expected_filesize
@@ -65,7 +67,8 @@ def test_cli(
             platform_name,
             image_name,
             ".",
-        ]
+        ],
+        check=False,
     )
     assert ps.returncode == 0
     assert expected_filepath.exists()