refactor: Implement (naive) msgspec encoding

singer_sdk/_singerlib/encoding/_msgspec.py

@@ -11,80 +11,11 @@
 from singer_sdk._singerlib.exceptions import InvalidInputLine
 
 from ._base import GenericSingerReader, GenericSingerWriter
+from ._simple import Message
 
 logger = logging.getLogger(__name__)
 
 
-class Message(msgspec.Struct, tag_field="type", tag=str.upper):
-    """Singer base message."""
-
-    def to_dict(self):  # noqa: ANN202
-        return {f: getattr(self, f) for f in self.__struct_fields__}
-
-
-class RecordMessage(Message, tag="RECORD"):
-    """Singer RECORD message."""
-
-    stream: str
-    record: t.Dict[str, t.Any]  # noqa: UP006
-    version: t.Union[int, None] = None  # noqa: UP007
-    time_extracted: t.Union[datetime.datetime, None] = None  # noqa: UP007
-
-    def __post_init__(self) -> None:
-        """Post-init processing.
-
-        Raises:
-            ValueError: If the time_extracted is not timezone-aware.
-        """
-        if self.time_extracted and not self.time_extracted.tzinfo:
-            msg = (
-                "'time_extracted' must be either None or an aware datetime (with a "
-                "time zone)"
-            )
-            raise ValueError(msg)
-
-        if self.time_extracted:
-            self.time_extracted = self.time_extracted.astimezone(datetime.timezone.utc)
-
-
-class SchemaMessage(Message, tag="SCHEMA"):
-    """Singer SCHEMA message."""
-
-    stream: str
-    schema: t.Dict[str, t.Any]  # noqa: UP006
-    key_properties: t.List[str]  # noqa: UP006
-    bookmark_properties: t.Union[t.List[str], None] = None  # noqa: UP006, UP007
-
-    def __post_init__(self) -> None:
-        """Post-init processing.
-
-        Raises:
-            ValueError: If bookmark_properties is not a string or list of strings.
-        """
-        if isinstance(self.bookmark_properties, (str, bytes)):
-            self.bookmark_properties = [self.bookmark_properties]
-        if self.bookmark_properties and not isinstance(self.bookmark_properties, list):
-            msg = "bookmark_properties must be a string or list of strings"
-            raise ValueError(msg)
-
-
-class StateMessage(Message, tag="STATE"):
-    """Singer state message."""
-
-    value: t.Dict[str, t.Any]  # noqa: UP006
-    """The state value."""
-
-
-class ActivateVersionMessage(Message, tag="ACTIVATE_VERSION"):
-    """Singer activate version message."""
-
-    stream: str
-    """The stream name."""
-
-    version: int
-    """The version to activate."""
-
-
 def enc_hook(obj: t.Any) -> t.Any:  # noqa: ANN401
     """Encoding type helper for non native types.
 
@@ -111,16 +42,7 @@ def dec_hook(type: type, obj: t.Any) -> t.Any:  # noqa: ARG001, A002, ANN401
 
 
 encoder = msgspec.json.Encoder(enc_hook=enc_hook, decimal_format="number")
-decoder = msgspec.json.Decoder(
-    t.Union[
-        RecordMessage,
-        SchemaMessage,
-        StateMessage,
-        ActivateVersionMessage,
-    ],
-    dec_hook=dec_hook,
-    float_hook=decimal.Decimal,
-)
+decoder = msgspec.json.Decoder(dec_hook=dec_hook, float_hook=decimal.Decimal)
 
 
 class MsgSpecReader(GenericSingerReader[str]):
@@ -141,7 +63,7 @@ def deserialize_json(self, line: str) -> dict:  # noqa: PLR6301
             InvalidInputLine: If the line cannot be parsed
         """
         try:
-            return decoder.decode(line).to_dict()  # type: ignore[no-any-return]
+            return decoder.decode(line)  # type: ignore[no-any-return]
         except msgspec.DecodeError as exc:
             logger.exception("Unable to parse:\n%s", line)
             msg = f"Unable to parse line as JSON: {line}"