fix: Parse record time_extracted into datetime instance

singer_sdk/_singerlib/messages.py

@@ -6,9 +6,10 @@
 import sys
 import typing as t
 from dataclasses import asdict, dataclass, field
+from datetime import timezone
 
-import pytz
 import simplejson as json
+from dateutil.parser import parse
 
 if t.TYPE_CHECKING:
     from datetime import datetime
@@ -84,6 +85,27 @@ class RecordMessage(Message):
     time_extracted: datetime | None = None
     """The time the record was extracted."""
 
+    @classmethod
+    def from_dict(cls: type[RecordMessage], data: dict[str, t.Any]) -> RecordMessage:
+        """Create a record message from a dictionary.
+
+        This overrides the default conversion logic, since it uses unnecessary
+        deep copying and is very slow.
+
+        Args:
+            data: The dictionary to create the message from.
+
+        Returns:
+            The created message.
+        """
+        time_extracted = data.get("time_extracted")
+        return cls(
+            stream=data["stream"],
+            record=data["record"],
+            version=data.get("version"),
+            time_extracted=parse(time_extracted) if time_extracted else None,
+        )
+
     def to_dict(self) -> dict[str, t.Any]:
         """Return a dictionary representation of the message.
 
@@ -119,7 +141,7 @@ def __post_init__(self) -> None:
             raise ValueError(msg)
 
         if self.time_extracted:
-            self.time_extracted = self.time_extracted.astimezone(pytz.utc)
+            self.time_extracted = self.time_extracted.astimezone(timezone.utc)
 
 
 @dataclass

tests/_singerlib/test_messages.py

@@ -1,15 +1,17 @@
 from __future__ import annotations
 
+import datetime
 import io
 from contextlib import redirect_stdout
-from datetime import datetime
 
 import pytest
-from pytz import UTC, timezone
+from pytz import timezone
 
 import singer_sdk._singerlib as singer
 from singer_sdk._singerlib.messages import format_message
 
+UTC = datetime.timezone.utc
+
 
 def test_exclude_null_dict():
     pairs = [("a", 1), ("b", None), ("c", 3)]
@@ -55,27 +57,41 @@ def test_record_message():
     assert singer.RecordMessage.from_dict(record.to_dict()) == record
 
 
+def test_record_message_parse_time_extracted():
+    message_dic = {
+        "type": "RECORD",
+        "stream": "test",
+        "record": {"id": 1, "name": "test"},
+        "time_extracted": "2021-01-01T00:00:00Z",
+    }
+    record = singer.RecordMessage.from_dict(message_dic)
+    assert record.type == "RECORD"
+    assert record.stream == "test"
+    assert record.record == {"id": 1, "name": "test"}
+    assert record.time_extracted == datetime.datetime(2021, 1, 1, 0, 0, 0, tzinfo=UTC)
+
+
 def test_record_message_naive_time_extracted():
     """Check that record message' time_extracted must be timezone-aware."""
     with pytest.raises(ValueError, match="must be either None or an aware datetime"):
         singer.RecordMessage(
             stream="test",
             record={"id": 1, "name": "test"},
-            time_extracted=datetime(2021, 1, 1),  # noqa: DTZ001
+            time_extracted=datetime.datetime(2021, 1, 1),  # noqa: DTZ001
         )
 
 
 def test_record_message_time_extracted_to_utc():
     """Check that record message's time_extracted is converted to UTC."""
-    naive = datetime(2021, 1, 1, 12)  # noqa: DTZ001
+    naive = datetime.datetime(2021, 1, 1, 12)  # noqa: DTZ001
     nairobi = timezone("Africa/Nairobi")
 
     record = singer.RecordMessage(
         stream="test",
         record={"id": 1, "name": "test"},
         time_extracted=nairobi.localize(naive),
     )
-    assert record.time_extracted == datetime(2021, 1, 1, 9, tzinfo=UTC)
+    assert record.time_extracted == datetime.datetime(2021, 1, 1, 9, tzinfo=UTC)
 
 
 def test_schema_message():