Feature/datetime conversion fix (#179)

pyproject.toml

@@ -30,6 +30,7 @@ opentelemetry-api = { version = "^1.11.1", optional = true }
 opentelemetry-sdk = { version = "^1.11.1", optional = true }
 protobuf = "~4.21"
 python = "^3.7"
+python-dateutil = { version = "^2.8.2", python = "<3.11" }
 types-protobuf = "~3.20"
 typing-extensions = "^4.2.0"
 
@@ -121,7 +122,7 @@ ignore_missing_imports = true
 exclude = [
   # Ignore generated code
   'temporalio/api',
-  'temporalio/bridge/proto',
+  'temporalio/bridge/proto'
 ]
 
 [tool.pydocstyle]

temporalio/converter.py

@@ -14,6 +14,7 @@
 from enum import IntEnum
 from typing import (
     Any,
+    Callable,
     Dict,
     List,
     Mapping,
@@ -34,6 +35,9 @@
 import temporalio.api.common.v1
 import temporalio.common
 
+if sys.version_info < (3, 11):
+    # Python's datetime.fromisoformat doesn't support certain formats pre-3.11
+    from dateutil import parser  # type: ignore
 # StrEnum is available in 3.11+
 if sys.version_info >= (3, 11):
     from enum import StrEnum
@@ -682,6 +686,19 @@ def encode_search_attribute_values(
     return default().payload_converter.to_payloads([safe_vals])[0]
 
 
+def _get_iso_datetime_parser() -> Callable[[str], datetime]:
+    """Isolates system version check and returns relevant datetime passer
+
+    Returns:
+        A callable to parse date strings into datetimes.
+    """
+    if sys.version_info >= (3, 11):
+        return datetime.fromisoformat  # noqa
+    else:
+        # Isolate import for py > 3.11, as dependency only installed for < 3.11
+        return parser.isoparse
+
+
 def decode_search_attributes(
     api: temporalio.api.common.v1.SearchAttributes,
 ) -> temporalio.common.SearchAttributes:
@@ -702,7 +719,8 @@ def decode_search_attributes(
             val = [val]
         # Convert each item to datetime if necessary
         if v.metadata.get("type") == b"Datetime":
-            val = [datetime.fromisoformat(v) for v in val]
+            parser = _get_iso_datetime_parser()
+            val = [parser(v) for v in val]
         ret[k] = val
     return ret
 

tests/test_converter.py

@@ -4,7 +4,7 @@
 import sys
 from collections import deque
 from dataclasses import dataclass
-from datetime import datetime
+from datetime import datetime, timezone
 from enum import Enum, IntEnum
 from typing import (
     Any,
@@ -174,6 +174,43 @@ def test_encode_search_attribute_values():
         temporalio.converter.encode_search_attribute_values(["foo", 123])
 
 
+def test_decode_search_attributes():
+    """Tests decode from protobuf for python types"""
+
+    def payload(key, dtype, data, encoding=None):
+        if encoding is None:
+            encoding = {"encoding": b"json/plain"}
+        check = temporalio.api.common.v1.Payload(
+            data=bytes(data, encoding="utf-8"),
+            metadata={"type": bytes(dtype, encoding="utf-8"), **encoding},
+        )
+        return temporalio.api.common.v1.SearchAttributes(indexed_fields={key: check})
+
+    # Check basic keyword parsing works
+    kw_check = temporalio.converter.decode_search_attributes(
+        payload("kw", "Keyword", '"test-id"')
+    )
+    assert kw_check["kw"][0] == "test-id"
+
+    # Ensure original DT functionality works
+    dt_check = temporalio.converter.decode_search_attributes(
+        payload("dt", "Datetime", '"2020-01-01T00:00:00"')
+    )
+    assert dt_check["dt"][0] == datetime(2020, 1, 1, 0, 0, 0)
+
+    # Check timezone aware works as server is using ISO 8601
+    dttz_check = temporalio.converter.decode_search_attributes(
+        payload("dt", "Datetime", '"2020-01-01T00:00:00Z"')
+    )
+    assert dttz_check["dt"][0] == datetime(2020, 1, 1, 0, 0, 0, tzinfo=timezone.utc)
+
+    # Check timezone aware, hour offset
+    dttz_check = temporalio.converter.decode_search_attributes(
+        payload("dt", "Datetime", '"2020-01-01T00:00:00+00:00"')
+    )
+    assert dttz_check["dt"][0] == datetime(2020, 1, 1, 0, 0, 0, tzinfo=timezone.utc)
+
+
 NewIntType = NewType("NewIntType", int)
 MyDataClassAlias = MyDataClass