fix: record a release only from finished packs

scripts/release_record.py

@@ -24,7 +24,7 @@ import zipfile
 from pathlib import Path
 
 import split_pack
-from common import write_text_atomic
+from common import ArtifactLockBusy, artifact_lock, write_text_atomic
 
 RECORD = "release.json"
 
@@ -34,11 +34,32 @@ def _match_key(value: str) -> str:
     return re.sub(r"[^a-z0-9]", "", value.lower())
 
 
+class UnfinishedSplit(Exception):
+    """A pack lies beside its own parts: a split is running or was killed."""
+
+
 def build_record(dist: Path, tag: str) -> dict:
-    """Read every pack of a directory, parts counted once across them."""
+    """Read every pack of a directory, parts counted once across them.
+
+    Read under the shared artifact lock, so a split that is reading its parts
+    back cannot be recorded half done. A pack still beside its parts after
+    that is a split that never finished: summed, it doubled the download size
+    and named an asset that is never published.
+    """
+    with artifact_lock(str(dist), exclusive=False):
+        return _read_record(Path(dist), tag)
+
+
+def _read_record(dist: Path, tag: str) -> dict:
     assets: dict[str, list[Path]] = {}
-    for path in sorted(Path(dist).glob("*_BIOS_Pack*.zip")):
+    for path in sorted(dist.glob("*_BIOS_Pack*.zip")):
         assets.setdefault(split_pack.pack_of(path.name), []).append(path)
+    for name, paths in sorted(assets.items()):
+        whole = [p for p in paths if not split_pack.is_part(p.name)]
+        if whole and len(paths) > len(whole):
+            raise UnfinishedSplit(
+                f"{whole[0].name} lies beside its parts: the split did not finish"
+            )
 
     packs = {}
     for name, paths in sorted(assets.items()):
@@ -110,7 +131,11 @@ def main() -> int:
     parser.add_argument("--output", default=RECORD, type=Path)
     args = parser.parse_args()
 
+    try:
         record = build_record(args.dist, args.tag)
+    except (UnfinishedSplit, ArtifactLockBusy) as exc:
+        print(f"Error: {exc}", file=sys.stderr)
+        return 1
     if not record["packs"]:
         print(f"Error: no pack in {args.dist}", file=sys.stderr)
         return 1

tests/test_pack_counts.py

@@ -352,6 +352,22 @@ class ReleaseRecord(unittest.TestCase):
         )
 
 
+    def test_a_pack_beside_its_parts_is_refused(self):
+        """A split reading its parts back, or one killed before removing the
+        pack, leaves both: summed, the download size doubled."""
+        self._pack(
+            "Demo_2.0_BIOS_Pack.zip",
+            {f"dir/file{n}.bin": bytes([n]) * 700 + bytes(range(256)) for n in range(6)},
+        )
+        with self.assertRaises(release_record.UnfinishedSplit):
+            release_record.build_record(self.dist, "v1")
+
+    def test_a_directory_being_written_is_not_read(self):
+        with common.artifact_lock(str(self.dist)), \
+                self.assertRaises(common.ArtifactLockBusy):
+            release_record.build_record(self.dist, "v1")
+
+
 class TheCollectionTotalNamesTheCollection(unittest.TestCase):
     COMPOSITION = {
         "systems": {"files": 5030},