refactor: Remove pytz dependency and use datetime.timezone.utc in…

…stead of `pytz.UTC` where possible (#2157)

.gitignore

@@ -1,3 +1,7 @@
+# Local Poetry configuration file
+
+poetry.toml
+
 # CI
 
 _changelog_fragment.md

noxfile.py

@@ -42,11 +42,12 @@
     "coverage[toml]",
     "duckdb",
     "duckdb-engine",
+    "pyarrow",
     "pytest",
     "pytest-benchmark",
     "pytest-durations",
     "pytest-snapshot",
-    "pyarrow",
+    "pytz",
     "requests-mock",
     "rfc3339-validator",
     "time-machine",

pyproject.toml

@@ -63,7 +63,6 @@ pendulum = [
 PyJWT = "~=2.4"
 python-dateutil = ">=2.8.2"
 python-dotenv = ">=0.20"
-pytz = ">=2022.2.1"
 PyYAML = ">=6.0"
 requests = ">=2.25.1"
 simpleeval = ">=0.9.13"
@@ -136,6 +135,7 @@ mypy = [
 ]
 pytest-benchmark = ">=4.0.0"
 pytest-snapshot = ">=0.9.0"
+pytz = ">=2022.2.1"
 requests-mock = ">=1.10.0"
 rfc3339-validator = ">=0.1.4"
 time-machine = [
@@ -214,7 +214,6 @@ fail_under = 82
 [tool.mypy]
 exclude = "tests"
 files = "singer_sdk"
-python_version = "3.8"
 warn_redundant_casts = true
 warn_return_any = true
 warn_unused_configs = true

singer_sdk/_singerlib/utils.py

@@ -1,9 +1,7 @@
 from __future__ import annotations
 
 import sys
-from datetime import datetime, timedelta
-
-import pytz
+from datetime import datetime, timedelta, timezone
 
 if sys.version_info < (3, 11):
     from backports.datetime_fromisoformat import MonkeyPatch
@@ -33,9 +31,9 @@ def strptime_to_utc(dtimestr: str) -> datetime:
     """
     d_object: datetime = datetime.fromisoformat(dtimestr)
     if d_object.tzinfo is None:
-        return d_object.replace(tzinfo=pytz.UTC)
+        return d_object.replace(tzinfo=timezone.utc)
 
-    return d_object.astimezone(tz=pytz.UTC)
+    return d_object.astimezone(tz=timezone.utc)
 
 
 def strftime(dtime: datetime, format_str: str = DATETIME_FMT) -> str:

singer_sdk/helpers/_resources.py

@@ -6,12 +6,12 @@
 if t.TYPE_CHECKING:
     from types import ModuleType
 
+    from singer_sdk.helpers._compat import Traversable
+
 if sys.version_info < (3, 9):
     import importlib_resources
-    from importlib_resources.abc import Traversable
 else:
     import importlib.resources as importlib_resources
-    from importlib.abc import Traversable
 
 
 def get_package_files(package: str | ModuleType) -> Traversable:
@@ -24,4 +24,4 @@ def get_package_files(package: str | ModuleType) -> Traversable:
     Returns:
         The file as a Traversable object.
     """
-    return t.cast(Traversable, importlib_resources.files(package))
+    return importlib_resources.files(package)

singer_sdk/metrics.py

@@ -15,11 +15,13 @@
 
 import yaml
 
-from singer_sdk.helpers._resources import Traversable, get_package_files
+from singer_sdk.helpers._resources import get_package_files
 
 if t.TYPE_CHECKING:
     from types import TracebackType
 
+    from singer_sdk.helpers._compat import Traversable
+
 DEFAULT_LOG_INTERVAL = 60.0
 METRICS_LOGGER_NAME = __name__
 METRICS_LOG_LEVEL_SETTING = "metrics_log_level"

singer_sdk/testing/templates.py

@@ -337,4 +337,4 @@ def singer_filepath(self) -> Traversable:
         Returns:
             The expected Path to this tests singer file.
         """
-        return importlib_resources.files(target_test_streams) / f"{self.name}.singer"  # type: ignore[no-any-return]
+        return importlib_resources.files(target_test_streams) / f"{self.name}.singer"

tests/_singerlib/test_utils.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from datetime import datetime
+from datetime import datetime, timezone
 
 import pytest
 import pytz
@@ -30,11 +30,12 @@ def test_round_trip():
         "2021-01-01T00:00:00.000000+00:00",
         "2021-01-01T00:00:00.000000+06:00",
         "2021-01-01T00:00:00.000000-04:00",
+        "2021-01-01T00:00:00.000000",
     ],
-    ids=["Z", "offset+0", "offset+6", "offset-4"],
+    ids=["Z", "offset+0", "offset+6", "offset-4", "no offset"],
 )
 def test_strptime_to_utc(dtimestr):
-    assert strptime_to_utc(dtimestr).tzinfo == pytz.UTC
+    assert strptime_to_utc(dtimestr).tzinfo == timezone.utc
 
 
 def test_stftime_non_utc():