fix(storage): skip downloading blobs whose name contain ":" eg: C: D: etc when application runs in Windows. (#1774)

skip downloading blobs whose name contain `":" ` eg: `C:` `D:` etc when
application runs in Windows.

Author: chandra-siri

google/cloud/storage/exceptions.py

@@ -33,6 +33,12 @@
     DataCorruptionDynamicParent = Exception
 
 
+class InvalidPathError(Exception):
+    """Raised when the provided path string is malformed."""
+
+    pass
+
+
 class InvalidResponse(InvalidResponseDynamicParent):
     """Error class for responses which are not in the correct state.
 

google/cloud/storage/transfer_manager.py

@@ -39,7 +39,7 @@
 
 from google.cloud.storage._media.requests.upload import XMLMPUContainer
 from google.cloud.storage._media.requests.upload import XMLMPUPart
-from google.cloud.storage.exceptions import DataCorruption
+from google.cloud.storage.exceptions import DataCorruption, InvalidPathError
 
 TM_DEFAULT_CHUNK_SIZE = 32 * 1024 * 1024
 DEFAULT_MAX_WORKERS = 8
@@ -263,6 +263,8 @@ def upload_many(
 
 
 def _resolve_path(target_dir, blob_path):
+    if os.name == "nt" and ":" in blob_path:
+        raise InvalidPathError(f"{blob_path} cannot be downloaded into {target_dir}")
     target_dir = Path(target_dir)
     blob_path = Path(blob_path)
     # blob_path.anchor will be '/' if `blob_path` is full path else it'll empty.
@@ -818,7 +820,13 @@ def download_many_to_path(
 
     for i, blob_name in enumerate(blob_names):
         full_blob_name = blob_name_prefix + blob_name
-        resolved_path = _resolve_path(destination_directory, blob_name)
+        try:
+            resolved_path = _resolve_path(destination_directory, blob_name)
+        except InvalidPathError as e:
+            msg = f"The blob {blob_name} will **NOT** be downloaded. {e}"
+            warnings.warn(msg)
+            results[i] = UserWarning(msg)
+            continue
         if not resolved_path.parent.is_relative_to(
             Path(destination_directory).resolve()
         ):

tests/unit/test_transfer_manager.py

@@ -513,6 +513,57 @@ def test_upload_many_from_filenames_additional_properties():
         assert getattr(blob, attrib) == value
 
 
+
+def test__resolve_path_raises_invalid_path_error_on_windows():
+    from google.cloud.storage.transfer_manager import _resolve_path, InvalidPathError
+
+    with mock.patch("os.name", "nt"):
+        with pytest.raises(InvalidPathError) as exc_info:
+            _resolve_path("C:\\target", "C:\\target\\file.txt")
+        assert "cannot be downloaded into" in str(exc_info.value)
+
+    # Test that it DOES NOT raise on non-windows
+    with mock.patch("os.name", "posix"):
+        # Should not raise
+        _resolve_path("/target", "C:\\target\\file.txt")
+
+
+def test_download_many_to_path_raises_invalid_path_error():
+    bucket = mock.Mock()
+
+    BLOBNAMES = ["C:\\target\\file.txt"]
+    PATH_ROOT = "mypath/"
+    BLOB_NAME_PREFIX = "myprefix/"
+    DOWNLOAD_KWARGS = {"accept-encoding": "fake-gzip"}
+    MAX_WORKERS = 7
+    DEADLINE = 10
+    WORKER_TYPE = transfer_manager.THREAD
+
+    with mock.patch("os.name", "nt"):
+        import warnings
+
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter("always")
+            results = transfer_manager.download_many_to_path(
+                bucket,
+                BLOBNAMES,
+                destination_directory=PATH_ROOT,
+                blob_name_prefix=BLOB_NAME_PREFIX,
+                download_kwargs=DOWNLOAD_KWARGS,
+                deadline=DEADLINE,
+                create_directories=False,
+                raise_exception=True,
+                max_workers=MAX_WORKERS,
+                worker_type=WORKER_TYPE,
+                skip_if_exists=True,
+            )
+
+    assert len(w) == 1
+    assert "will **NOT** be downloaded" in str(w[0].message)
+    assert len(results) == 1
+    assert isinstance(results[0], UserWarning)
+
+
 def test_download_many_to_path():
     bucket = mock.Mock()