fix: Add deprecation warning for python 3.7

gapic/templates/%namespace/%name/__init__.py.j2

@@ -1,6 +1,9 @@
 {% extends '_base.py.j2' %}
 {% block content %}
 
+import sys
+import warnings
+
 {% set package_path = api.naming.module_namespace|join('.') + "." + api.naming.module_name %}
 from {{package_path}} import gapic_version as package_version
 
@@ -48,6 +51,27 @@ from {% if api.naming.module_namespace %}{{ api.naming.module_namespace|join('.'
     them again.
 #}
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # Configure the Python37DeprecationWarning warning so that it is only emitted once.
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
+
 __all__ = (
 {%- filter indent %}
 {% for subpackage, _ in api.subpackages|dictsort %}

gapic/templates/%namespace/%name_%version/%sub/__init__.py.j2

@@ -2,6 +2,9 @@
 
 {% block content %}
 
+import sys
+import warnings
+
 {% set package_path = api.naming.module_namespace|join('.') + "." + api.naming.versioned_module_name %}
 from {{package_path}} import gapic_version as package_version
 
@@ -36,6 +39,26 @@ from .types.{{ proto.module_name }} import {{ enum.name }}
 {% endfor %}
 {% endfor %}
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # print only the first occurrence of Python37DeprecationWarning, regardless of location
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
 {#  Define __all__.
     This requires the full set of imported names, so we iterate over
     them again.

tests/integration/goldens/asset/google/cloud/asset/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.cloud.asset import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -99,6 +102,27 @@
 from google.cloud.asset_v1.types.assets import TimeWindow
 from google.cloud.asset_v1.types.assets import VersionedResource
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # Configure the Python37DeprecationWarning warning so that it is only emitted once.
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
+
 __all__ = ('AssetServiceClient',
     'AssetServiceAsyncClient',
     'AnalyzeIamPolicyLongrunningMetadata',

tests/integration/goldens/asset/google/cloud/asset_v1/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.cloud.asset_v1 import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -99,6 +102,26 @@
 from .types.assets import TimeWindow
 from .types.assets import VersionedResource
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # print only the first occurrence of Python37DeprecationWarning, regardless of location
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
 __all__ = (
     'AssetServiceAsyncClient',
 'AnalyzeIamPolicyLongrunningMetadata',

tests/integration/goldens/credentials/google/iam/credentials/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.iam.credentials import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -30,6 +33,27 @@
 from google.iam.credentials_v1.types.common import SignJwtRequest
 from google.iam.credentials_v1.types.common import SignJwtResponse
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # Configure the Python37DeprecationWarning warning so that it is only emitted once.
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
+
 __all__ = ('IAMCredentialsClient',
     'IAMCredentialsAsyncClient',
     'GenerateAccessTokenRequest',

tests/integration/goldens/credentials/google/iam/credentials_v1/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.iam.credentials_v1 import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -30,6 +33,26 @@
 from .types.common import SignJwtRequest
 from .types.common import SignJwtResponse
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # print only the first occurrence of Python37DeprecationWarning, regardless of location
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
 __all__ = (
     'IAMCredentialsAsyncClient',
 'GenerateAccessTokenRequest',

tests/integration/goldens/eventarc/google/cloud/eventarc/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.cloud.eventarc import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -59,6 +62,27 @@
 from google.cloud.eventarc_v1.types.trigger import Transport
 from google.cloud.eventarc_v1.types.trigger import Trigger
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # Configure the Python37DeprecationWarning warning so that it is only emitted once.
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
+
 __all__ = ('EventarcClient',
     'EventarcAsyncClient',
     'Channel',

tests/integration/goldens/eventarc/google/cloud/eventarc_v1/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.cloud.eventarc_v1 import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -59,6 +62,26 @@
 from .types.trigger import Transport
 from .types.trigger import Trigger
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # print only the first occurrence of Python37DeprecationWarning, regardless of location
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
 __all__ = (
     'EventarcAsyncClient',
 'Channel',

tests/integration/goldens/logging/google/cloud/logging/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.cloud.logging import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -102,6 +105,27 @@
 from google.cloud.logging_v2.types.logging_metrics import LogMetric
 from google.cloud.logging_v2.types.logging_metrics import UpdateLogMetricRequest
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # Configure the Python37DeprecationWarning warning so that it is only emitted once.
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
+
 __all__ = ('ConfigServiceV2Client',
     'ConfigServiceV2AsyncClient',
     'LoggingServiceV2Client',

tests/integration/goldens/logging/google/cloud/logging_v2/__init__.py

@@ -13,6 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import sys
+import warnings
+
 from google.cloud.logging_v2 import gapic_version as package_version
 
 __version__ = package_version.__version__
@@ -102,6 +105,26 @@
 from .types.logging_metrics import LogMetric
 from .types.logging_metrics import UpdateLogMetricRequest
 
+
+class Python37DeprecationWarning(DeprecationWarning):
+    """
+    Deprecation warning raised when Python 3.7 runtime is detected.
+    Python 3.7 support will be dropped after January 1, 2024. See
+    https://cloud.google.com/python/docs/python37-sunset/ for more information.
+    """
+    pass
+
+# Checks if the current runtime is Python 3.7.
+if sys.version_info.major == 3 and sys.version_info.minor == 7:
+    message = (
+        "After January 1, 2024, new releases of this client library will drop support "
+        "for Python 3.7. More details about Python 3.7 support for Client Libraries "
+        "can be found at https://cloud.google.com/python/docs/python37-sunset/"
+    )
+    # print only the first occurrence of Python37DeprecationWarning, regardless of location
+    warnings.simplefilter('once', Python37DeprecationWarning)
+    warnings.warn(message, Python37DeprecationWarning)
+
 __all__ = (
     'ConfigServiceV2AsyncClient',
     'LoggingServiceV2AsyncClient',