fix: add ab_datetime_parse fallback in _parse_start_date for additional format support

Co-Authored-By: Daryna Ishchenko <darina.ishchenko17@gmail.com>

Author: devin-ai-integration[bot]

airbyte_cdk/sources/file_based/file_based_stream_reader.py

@@ -24,6 +24,7 @@
 from airbyte_cdk.sources.file_based.exceptions import FileSizeLimitError
 from airbyte_cdk.sources.file_based.file_record_data import FileRecordData
 from airbyte_cdk.sources.file_based.remote_file import RemoteFile, UploadableRemoteFile
+from airbyte_cdk.utils.datetime_helpers import ab_datetime_parse
 
 
 class FileReadMode(Enum):
@@ -114,7 +115,10 @@ def _parse_start_date(self, start_date_str: str) -> datetime:
         try:
             return datetime.strptime(start_date_str, self.DATE_TIME_FORMAT)
         except ValueError:
-            return datetime.strptime(start_date_str, "%Y-%m-%dT%H:%M:%SZ")
+            try:
+                return datetime.strptime(start_date_str, "%Y-%m-%dT%H:%M:%SZ")
+            except ValueError:
+                return ab_datetime_parse(start_date_str).replace(tzinfo=None)
 
     def filter_files_by_globs_and_start_date(
         self, files: List[RemoteFile], globs: List[str]

unit_tests/sources/file_based/test_file_based_stream_reader.py

@@ -524,6 +524,11 @@ def test_preserve_sub_directories_scenarios(
             datetime(2025, 12, 31, 23, 59, 59),
             id="without_microseconds_end_of_day",
         ),
+        pytest.param(
+            "2025-01-01",
+            datetime(2025, 1, 1, 0, 0, 0),
+            id="date_only_ab_datetime_parse_fallback",
+        ),
     ],
 )
 def test_parse_start_date(start_date_str: str, expected: datetime) -> None: