fix: resolve CI failures, drop Python 3.9, and clean up test deprecations

.github/workflows/presubmit.yaml

@@ -27,7 +27,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
+        python: ["3.10", "3.11", "3.12", "3.13", "3.14"]
 
     steps:
       - name: Checkout code

.kokoro/presubmit/integration-regular-sessions-enabled.cfg

@@ -3,7 +3,7 @@
 # Only run a subset of all nox sessions
 env_vars: {
     key: "NOX_SESSION"
-    value: "unit-3.9 unit-3.14 system-3.14"
+    value: "unit-3.14 system-3.14"
 }
 
 env_vars: {

.kokoro/test-samples-impl.sh

@@ -35,7 +35,7 @@ export PYTHONUNBUFFERED=1
 env | grep KOKORO
 
 # Install nox
-python3.9 -m pip install --upgrade --quiet nox
+python3 -m pip install --upgrade --quiet nox
 
 # Use secrets acessor service account to get secrets
 if [[ -f "${KOKORO_GFILE_DIR}/secrets_viewer_service_account.json" ]]; then
@@ -88,7 +88,7 @@ for file in samples/**/requirements.txt; do
     echo "------------------------------------------------------------"
 
     # Use nox to execute the tests for the project.
-    python3.9 -m nox -s "$RUN_TESTS_SESSION"
+    python3 -m nox -s "$RUN_TESTS_SESSION"
     EXIT=$?
 
     # If this is a periodic build, send the test log to the FlakyBot.

.librarian/generator-input/librarian.py

@@ -210,7 +210,7 @@
     split_system_tests=True,
     system_test_extras=["tracing"],
     system_test_python_versions=["3.12"],
-    unit_test_python_versions=["3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
+    unit_test_python_versions=["3.10", "3.11", "3.12", "3.13", "3.14"]
 )
 s.move(
     templated_files,

.librarian/generator-input/noxfile.py

@@ -32,13 +32,12 @@
 ISORT_VERSION = "isort==5.11.0"
 LINT_PATHS = ["google", "tests", "noxfile.py", "setup.py"]
 
-DEFAULT_PYTHON_VERSION = "3.14"
+DEFAULT_PYTHON_VERSION = "3.10"
 
 DEFAULT_MOCK_SERVER_TESTS_PYTHON_VERSION = "3.12"
 SYSTEM_TEST_PYTHON_VERSIONS: List[str] = ["3.14"]
 
 UNIT_TEST_PYTHON_VERSIONS: List[str] = [
-    "3.9",
     "3.10",
     "3.11",
     "3.12",

.librarian/generator-input/setup.py

@@ -83,7 +83,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
@@ -95,7 +94,7 @@
     packages=packages,
     install_requires=dependencies,
     extras_require=extras,
-    python_requires=">=3.9",
+    python_requires=">=3.10",
     include_package_data=True,
     zip_safe=False,
 )

.librarian/state.yaml

@@ -38,8 +38,7 @@ libraries:
       - ^scripts/fixup_
       - ^setup.py
       - ^testing/constraints-3.8
-      - ^testing/constraints-3.9
-      - ^testing/constraints-3.1
+      - ^testing/constraints-3.10
       - ^docs/conf.py
       - ^docs/_static
       - ^docs/spanner_v1/types_.rst

google/cloud/spanner_dbapi/cursor.py

@@ -505,15 +505,17 @@ def _fetch(self, cursor_statement_type, size=None):
                             raise
                         else:
                             self.transaction_helper.retry_transaction()
+        except Aborted as e:
+            exception = e
         except Exception as e:
             exception = e
-            raise
-        finally:
-            if not self._in_retry_mode:
-                self.transaction_helper.add_fetch_statement_for_retry(
-                    self, rows, exception, is_fetch_all
-                )
-            return rows
+
+        if not self._in_retry_mode:
+            self.transaction_helper.add_fetch_statement_for_retry(
+                self, rows, exception, is_fetch_all
+            )
+
+        return rows
 
     def _handle_DQL_with_snapshot(self, snapshot, sql, params):
         self._result_set = snapshot.execute_sql(

google/cloud/spanner_v1/metrics/metrics_exporter.py

@@ -20,6 +20,8 @@
     MONITORED_RESOURCE_LABELS,
     METRIC_LABELS,
     METRIC_NAMES,
+    MONITORED_RES_LABEL_KEY_PROJECT,
+    MONITORED_RES_LABEL_KEY_INSTANCE,
 )
 
 import logging
@@ -299,8 +301,8 @@ def _data_point_to_timeseries_pb(
         )
         return series
 
-    @staticmethod
     def _resource_metrics_to_timeseries_pb(
+        self,
         metrics_data: "MetricsData",
     ) -> List["TimeSeries"]:
         """
@@ -324,6 +326,28 @@ def _resource_metrics_to_timeseries_pb(
                         ) = CloudMonitoringMetricsExporter._extract_metric_labels(
                             data_point
                         )
+
+                        # Ensure project_id is present in monitored resource labels
+                        if (
+                            MONITORED_RES_LABEL_KEY_PROJECT
+                            not in monitored_resource_labels
+                        ):
+                            monitored_resource_labels[
+                                MONITORED_RES_LABEL_KEY_PROJECT
+                            ] = self.project_id
+
+                        # The OpenTelemetry exporter uses the 'spanner_instance_client' resource type,
+                        # which strictly requires both project_id and instance_id. However, some
+                        # Spanner API calls (like creating or listing instances) operate at the
+                        # project level and naturally lack an instance_id. We silently drop these
+                        # metrics here to prevent Cloud Monitoring from rejecting the entire batch
+                        # with a 400 InvalidArgument error.
+                        if (
+                            MONITORED_RES_LABEL_KEY_INSTANCE
+                            not in monitored_resource_labels
+                        ):
+                            continue
+
                         monitored_resource = CloudMonitoringMetricsExporter._resource_to_monitored_resource_pb(
                             resource_metric.resource, monitored_resource_labels
                         )

google/cloud/spanner_v1/pool.py

@@ -35,7 +35,9 @@
 
 from google.cloud.spanner_v1.metrics.metrics_capture import MetricsCapture
 
-_NOW = datetime.datetime.utcnow  # unit tests may replace
+
+def _NOW():
+    return datetime.datetime.now(datetime.timezone.utc)  # unit tests may replace
 
 
 class AbstractSessionPool(object):

google/cloud/spanner_v1/session.py

@@ -16,7 +16,7 @@
 
 from functools import total_ordering
 import time
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import MutableMapping, Optional
 
 from google.api_core.exceptions import Aborted
@@ -80,7 +80,7 @@ def __init__(self, database, labels=None, database_role=None, is_multiplexed=Fal
         self._labels: MutableMapping[str, str] = labels
         self._database_role: Optional[str] = database_role
         self._is_multiplexed: bool = is_multiplexed
-        self._last_use_time: datetime = datetime.utcnow()
+        self._last_use_time: datetime = datetime.now(timezone.utc)
 
     def __lt__(self, other):
         return self._session_id < other._session_id

noxfile.py

@@ -42,7 +42,6 @@
 SYSTEM_TEST_PYTHON_VERSIONS: List[str] = ["3.14"]
 
 UNIT_TEST_PYTHON_VERSIONS: List[str] = [
-    "3.9",
     "3.10",
     "3.11",
     "3.12",
@@ -81,7 +80,6 @@
 CURRENT_DIRECTORY = pathlib.Path(__file__).parent.absolute()
 
 nox.options.sessions = [
-    "unit-3.9",
     "unit-3.10",
     "unit-3.11",
     "unit-3.12",