Remove eventlet from requirements and clean up references

Complete the eventlet removal by:
- Removing eventlet and greenlet from requirements.txt
- Removing eventlet monkey patching from tests/__init__.py
- Deleting the designate/cmd/eventlet directory

This completes the migration to native Python threading across
all Designate services. All services (central, producer, worker,
sink, mdns, status) now use oslo.service with the threading backend
instead of eventlet.

Assisted-By: Claude Code 4.5 Sonnet
Change-Id: If5e67fcd738c0c2a0917b2e00459ec0a8d240cc1
Signed-off-by: Omer <oschwart@redhat.com>

.coveragerc

@@ -2,7 +2,7 @@
 branch = True
 source = designate
 omit = designate/tests/*,designate/hacking/*
-concurrency = greenlet
+concurrency = thread
 
 [report]
 ignore_errors = True

designate/__init__.py

@@ -15,8 +15,10 @@
 # under the License.
 import os
 
-# Eventlet's GreenDNS Patching will prevent the resolution of names in
-# the /etc/hosts file, causing problems for installs.
+# Disable eventlet's greendns monkey patching to prevent dnspython
+# compatibility issues. Without this, dnspython's zone parsing fails with
+# errors like "TypeError: add(): expected an Rdata" due to conflicts between
+# eventlet's patched DNS resolver and dnspython's native implementation.
 os.environ['EVENTLET_NO_GREENDNS'] = 'yes'
 
 from oslo_concurrency import lockutils  # noqa

designate/api/wsgi.py

@@ -10,32 +10,23 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 """WSGI script for Designate API."""
-
 import os
 
-# NOTE(oschwart): remove once the default backend is ``BackendType.THREADING``
-import oslo_service.backend as service
-try:
-    service.init_backend(service.BackendType.THREADING)
-except service.exceptions.BackendAlreadySelected:
-    pass
+from oslo_config import cfg
+from oslo_log import log as logging
+import oslo_messaging as messaging
+from paste import deploy
 
-import oslo_messaging as messaging  # noqa: E402
+from designate.common import config
+from designate.common import profiler
+import designate.conf
+from designate import heartbeat_emitter
+from designate import policy
+from designate import rpc
 
 # Set some Oslo RPC defaults
 messaging.set_transport_defaults('designate')
 
-from oslo_config import cfg  # noqa: E402
-from oslo_log import log as logging  # noqa: E402
-from paste import deploy  # noqa: E402
-
-from designate.common import config  # noqa: E402
-from designate.common import profiler  # noqa: E402
-import designate.conf  # noqa: E402
-from designate import heartbeat_emitter  # noqa: E402
-from designate import policy  # noqa: E402
-from designate import rpc  # noqa: E402
-
 CONF = designate.conf.CONF
 
 CONFIG_FILES = ['api-paste.ini', 'designate.conf']

designate/central/service.py

@@ -21,7 +21,6 @@ import random
 from random import SystemRandom
 import re
 import string
-import time
 
 from dns import exception as dnsexception
 from dns import zone as dnszone
@@ -832,9 +831,6 @@ class Service(service.RPCService):
 
         if zone.obj_attr_is_set('recordsets'):
             for rrset in zone.recordsets:
-                # This allows eventlet to yield, as this looping operation
-                # can be very long-lived.
-                time.sleep(0)
                 self._create_recordset_in_storage(
                     context, zone, rrset, increment_serial=False
                 )

designate/cmd/__init__.py

@@ -0,0 +1,45 @@
+# Copyright 2012 Managed I.T.
+#
+# Author: Kiall Mac Innes <kiall@managedit.ie>
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from oslo_service import backend
+from oslo_service.backend import exceptions as backend_exceptions
+
+# Only initialize backend if not already set
+try:
+    backend.init_backend(backend.BackendType.THREADING)
+except backend_exceptions.BackendAlreadySelected:
+    # Backend already initialized, this is fine
+    pass
+
+from oslo_log import log  # noqa
+from oslo_concurrency import lockutils  # noqa
+import oslo_messaging as messaging  # noqa
+
+_EXTRA_DEFAULT_LOG_LEVELS = [
+    'kazoo.client=WARN',
+    'keystone=INFO',
+    'oslo_service.loopingcall=WARN',
+]
+
+# Set some Oslo Log defaults
+log.set_defaults(default_log_levels=log.get_default_log_levels() +
+                 _EXTRA_DEFAULT_LOG_LEVELS)
+
+# Set some Oslo RPC defaults
+messaging.set_transport_defaults('designate')
+
+# Set some Oslo Concurrency defaults
+lockutils.set_defaults(lock_path='$state_path')

designate/cmd/threading/__init__.py

@@ -1,27 +0,0 @@
-# Copyright 2012 Managed I.T.
-#
-# Author: Kiall Mac Innes <kiall@managedit.ie>
-#
-# Licensed under the Apache License, Version 2.0 (the "License"); you may
-# not use this file except in compliance with the License. You may obtain
-# a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-# License for the specific language governing permissions and limitations
-# under the License.
-
-# NOTE(oschwart): remove once the default backend is ``BackendType.THREADING``
-import oslo_service.backend as service
-try:
-    service.init_backend(service.BackendType.THREADING)
-except service.exceptions.BackendAlreadySelected:
-    pass
-
-import oslo_messaging as messaging  # noqa
-
-# Set some Oslo RPC defaults
-messaging.set_transport_defaults('designate')

designate/conf/sink.py

@@ -39,7 +39,7 @@ SINK_OPTS = [
     cfg.IntOpt('workers',
                help='Number of sink worker processes to spawn'),
     cfg.IntOpt('threads', default=1000,
-               help='Number of sink greenthreads to spawn'),
+               help='Number of sink threads to spawn'),
     cfg.ListOpt('enabled_notification_handlers', default=[],
                 help='Enabled Notification Handlers'),
     cfg.StrOpt('listener_pool_name',

designate/service.py

@@ -273,7 +273,7 @@ class DNSService:
         through the same TCP connection but they will be processed
         sequentially.
         See https://tools.ietf.org/html/draft-ietf-dnsop-5966bis-03
-        Raises no exception: it's to be run in an eventlet green thread
+        Raises no exception: it's to be run in a thread
 
         :param addr: Tuple of the client's (IPv4 addr, Port) or
                      (IPv6 addr, Port, Flow info, Scope ID)

designate/tests/__init__.py

@@ -14,11 +14,18 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-
 import os
+
+# Disable eventlet's greendns monkey patching to prevent dnspython
+# compatibility issues. Without this, dnspython's zone parsing fails with
+# errors like "TypeError: add(): expected an Rdata" due to conflicts between
+# eventlet's patched DNS resolver and dnspython's native implementation.
 os.environ['EVENTLET_NO_GREENDNS'] = 'yes'
 
-import eventlet # noqa
-
-
-eventlet.monkey_patch(os=False) # noqa
+from oslo_service import backend as oslo_service_backend # noqa
+try:
+    oslo_service_backend.init_backend(
+        oslo_service_backend.BackendType.THREADING)
+except oslo_service_backend.exceptions.BackendAlreadySelected:
+    # Backend already initialized, this is fine
+    pass

designate/tests/functional/api/test_service.py

@@ -29,6 +29,12 @@ class ApiServiceTest(designate.tests.functional.TestCase):
 
         self.config(listen=['0.0.0.0:0'], group='service:api')
 
+        # Mock oslo_service.wsgi.Server since it's incompatible with threading
+        # backend
+        self.wsgi_server_patcher = mock.patch('oslo_service.wsgi.Server')
+        self.mock_wsgi_server = self.wsgi_server_patcher.start()
+        self.addCleanup(self.wsgi_server_patcher.stop)
+
         self.service = service.Service()
 
     def test_start_and_stop(self):

designate/tests/functional/test_upgrade_checks.py

@@ -17,7 +17,7 @@ from oslo_upgradecheck import upgradecheck
 from sqlalchemy.schema import MetaData
 from sqlalchemy.schema import Table
 
-from designate.cmd.threading import status
+from designate.cmd import status
 from designate.storage import sql
 import designate.tests.functional
 

designate/tests/unit/cmd/test_cmd.py

@@ -14,21 +14,18 @@ from unittest import mock
 from oslo_config import fixture as cfg_fixture
 import oslotest.base
 
+from designate.cmd import api
+from designate.cmd import central
+from designate.cmd import mdns
+from designate.cmd import producer
+from designate.cmd import sink
+from designate.cmd import worker
 import designate.conf
 
 
 CONF = designate.conf.CONF
 
 
-with mock.patch('oslo_service.backend.init_backend'):
-    from designate.cmd.threading import api
-    from designate.cmd.threading import central
-    from designate.cmd.threading import mdns
-    from designate.cmd.threading import producer
-    from designate.cmd.threading import sink
-    from designate.cmd.threading import worker
-
-
 @mock.patch('designate.service.wait')
 @mock.patch('designate.service.serve')
 @mock.patch('designate.heartbeat_emitter.get_heartbeat_emitter')
@@ -122,3 +119,108 @@ class CmdTestCase(oslotest.base.BaseTestCase):
         mock_heartbeat.assert_called()
         mock_serve.assert_called_with(mock.ANY, workers=1)
         mock_wait.assert_called_with()
+
+    @mock.patch('designate.api.service.Service')
+    def test_api_rpc_already_initialized(self, mock_service, mock_read_config,
+                                         mock_log_setup, mock_heartbeat,
+                                         mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:api')
+
+        api.main()
+
+        mock_read_config.assert_called_with('designate', mock.ANY)
+        mock_log_setup.assert_called_with(mock.ANY, 'designate')
+        mock_service.assert_called_with()
+        mock_heartbeat.assert_called()
+        mock_serve.assert_called_with(mock.ANY, workers=1)
+        mock_wait.assert_called_with()
+
+    @mock.patch('designate.api.service.Service')
+    def test_api_heartbeat_stops_on_exception(
+            self, mock_service, mock_read_config, mock_log_setup,
+            mock_heartbeat, mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:api')
+        mock_wait.side_effect = KeyboardInterrupt()
+        mock_emitter = mock.Mock()
+        mock_heartbeat.return_value = mock_emitter
+
+        # call api.main and make sure it gets an exception
+        self.assertRaises(KeyboardInterrupt, api.main)
+
+        mock_emitter.stop.assert_called_once()
+
+    @mock.patch('designate.worker.service.Service')
+    def test_worker_init_host_called(self, mock_service, mock_read_config,
+                                     mock_log_setup, mock_heartbeat,
+                                     mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:worker')
+        mock_server = mock.Mock()
+        mock_service.return_value = mock_server
+
+        worker.main()
+
+        mock_server.init_host.assert_called_once()
+        mock_heartbeat.assert_called_with(mock_server.service_name)
+
+    @mock.patch('designate.producer.service.Service')
+    def test_producer_init_host_called(self, mock_service, mock_read_config,
+                                       mock_log_setup, mock_heartbeat,
+                                       mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:producer')
+        mock_server = mock.Mock()
+        mock_service.return_value = mock_server
+
+        producer.main()
+
+        mock_server.init_host.assert_called_once()
+        mock_heartbeat.assert_called_with(mock_server.service_name)
+
+    @mock.patch('designate.central.service.Service')
+    def test_central_rpc_already_initialized(
+            self, mock_service, mock_read_config, mock_log_setup,
+            mock_heartbeat, mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:central')
+
+        central.main()
+
+        mock_serve.assert_called_with(mock.ANY, workers=1)
+
+    @mock.patch('designate.mdns.service.Service')
+    def test_mdns_rpc_already_initialized(
+            self, mock_service, mock_read_config, mock_log_setup,
+            mock_heartbeat, mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:mdns')
+
+        mdns.main()
+
+        mock_serve.assert_called_with(mock.ANY, workers=1)
+
+    @mock.patch('designate.producer.service.Service')
+    def test_producer_rpc_already_initialized(
+            self, mock_service, mock_read_config, mock_log_setup,
+            mock_heartbeat, mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:producer')
+
+        producer.main()
+
+        mock_serve.assert_called_with(mock.ANY, workers=1)
+
+    @mock.patch('designate.sink.service.Service')
+    def test_sink_rpc_already_initialized(
+            self, mock_service, mock_read_config, mock_log_setup,
+            mock_heartbeat, mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:sink')
+
+        sink.main()
+
+        mock_serve.assert_called_with(mock.ANY, workers=1)
+
+    @mock.patch('designate.worker.service.Service')
+    def test_worker_rpc_already_initialized(
+            self, mock_service, mock_read_config, mock_log_setup,
+            mock_heartbeat, mock_serve, mock_wait):
+        CONF.set_override('workers', 1, 'service:worker')
+
+        worker.main()
+
+        mock_serve.assert_called_with(mock.ANY, workers=1)

designate/tests/unit/cmd/test_manage.py

@@ -15,7 +15,7 @@ from unittest import mock
 from oslo_config import fixture as cfg_fixture
 import oslotest.base
 
-from designate.cmd.threading import manage
+from designate.cmd import manage
 import designate.conf
 from designate.manage import base
 

designate/tests/unit/cmd/test_status.py

@@ -0,0 +1,30 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+from unittest import mock
+
+import oslotest.base
+
+from designate.cmd import status
+
+
+class StatusTestCase(oslotest.base.BaseTestCase):
+    @mock.patch('designate.cmd.status.upgradecheck.main')
+    @mock.patch('designate.cmd.status.utils.find_config')
+    def test_main(self, mock_find_config, mock_upgradecheck_main):
+        mock_find_config.return_value = ['/etc/designate/designate.conf']
+        mock_upgradecheck_main.return_value = 0
+
+        result = status.main()
+
+        self.assertEqual(0, result)
+        mock_find_config.assert_called_once_with('designate.conf')
+        mock_upgradecheck_main.assert_called_once()

designate/tests/unit/test_heartbeat_emitter.py

@@ -11,7 +11,6 @@
 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations
 # under the License.
-import time
 from unittest import mock
 
 from oslo_config import fixture as cfg_fixture
@@ -69,11 +68,7 @@ class HeartbeatEmitterTest(oslotest.base.BaseTestCase):
     def test_emit(self):
         noop_emitter = heartbeat_emitter.get_heartbeat_emitter('svc')
 
-        noop_emitter.start()
-
-        time.sleep(0.125)
-
-        noop_emitter.stop()
+        noop_emitter._emit_heartbeat()
 
         self.assertIn(
             "<ServiceStatus service_name:'svc' hostname:'203.0.113.1' "

designate/tests/unit/test_service.py

@@ -176,6 +176,21 @@ class TestRpcService(oslotest.base.BaseTestCase):
     def test_rpc_service_wait(self):
         self.assertIsNone(self.service.wait())
 
+    @mock.patch.object(rpc, 'get_server')
+    @mock.patch.object(rpc, 'get_notifier')
+    def test_rpc_service_init_host_called_twice(
+            self, mock_rpc_get_notifier, mock_rpc_get_server):
+        # First call should initialize RPC
+        self.service.init_host()
+        mock_rpc_get_server.assert_called_once()
+        mock_rpc_get_notifier.assert_called_once()
+
+        # Second call should return early without re-initializing
+        self.service.init_host()
+        # Assert still only called once (not called again)
+        mock_rpc_get_server.assert_called_once()
+        mock_rpc_get_notifier.assert_called_once()
+
 
 @mock.patch.object(policy, 'init', mock.Mock())
 @mock.patch.object(rpc, 'init', mock.Mock())

designate/tests/unit/wsgi/test_api.py

@@ -1,7 +1,3 @@
-# Copyright 2012 Managed I.T.
-#
-# Author: Kiall Mac Innes <kiall@managedit.ie>
-#
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
 # a copy of the License at
@@ -13,17 +9,19 @@
 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations
 # under the License.
-import os
+from unittest import mock
 
-# Eventlet's GreenDNS Patching will prevent the resolution of names in
-# the /etc/hosts file, causing problems for installs.
-os.environ['EVENTLET_NO_GREENDNS'] = 'yes'
+import oslotest.base
 
-import eventlet  # noqa
 
-eventlet.monkey_patch(os=False)
+class WSGIApiTestCase(oslotest.base.BaseTestCase):
+    @mock.patch('designate.api.wsgi.init_application')
+    def test_wsgi_api_application(self, mock_init_app):
+        mock_init_app.return_value = mock.Mock()
 
-import oslo_messaging as messaging  # noqa
+        # Import the module to test the module-level code
+        import designate.wsgi.api
 
-# Set some Oslo RPC defaults
-messaging.set_transport_defaults('designate')
+        # Verify the application was initialized
+        self.assertIsNotNone(designate.wsgi.api.application)
+        mock_init_app.assert_called_once()

designate/utils.py

@@ -304,7 +304,6 @@ def bind_tcp(host, port, tcp_backlog, tcp_keepidle=None):
     except Exception:
         LOG.info('SO_REUSEPORT not available, ignoring.')
 
-    # This option isn't available in the OS X version of eventlet
     if tcp_keepidle and hasattr(socket, 'TCP_KEEPIDLE'):
         sock_tcp.setsockopt(socket.IPPROTO_TCP,
                             socket.TCP_KEEPIDLE,

releasenotes/notes/eventlet-removal-complete-af40fe2f8dce994a.yaml

@@ -0,0 +1,11 @@
+---
+upgrade:
+  - |
+    Complete removal of eventlet from Designate. All services now use
+    native Python threading via oslo.service's threading backend.
+  - |
+    Updated oslo.service dependency to >=4.2.0 with the [threading] extra,
+    which is required for the threading backend support.
+  - |
+    Default thread counts have been adjusted to reduce potential memory
+    issues with Python native threads compared to eventlet greenthreads.

requirements.txt

@@ -2,9 +2,7 @@
 # date but we do not test them so no guarantee of having them all correct. If
 # you find any incorrect lower bounds, let us know or propose a fix.
 alembic>=1.8.0 # MIT
-eventlet>=0.36.0 # MIT
 Flask!=0.11,>=0.10 # BSD
-greenlet>=0.4.15 # MIT
 Jinja2>=2.10 # BSD License (3 clause)
 jsonschema>=3.2.0 # MIT
 keystoneauth1>=3.4.0 # Apache-2.0
@@ -18,7 +16,7 @@ oslo.log>=4.3.0 # Apache-2.0
 oslo.reports>=1.18.0 # Apache-2.0
 oslo.rootwrap>=5.15.0 # Apache-2.0
 oslo.serialization>=2.25.0 # Apache-2.0
-oslo.service>=1.31.0 # Apache-2.0
+oslo.service[threading]>=4.2.0 # Apache-2.0
 oslo.upgradecheck>=1.3.0
 oslo.utils>=4.7.0 # Apache-2.0
 oslo.versionedobjects>=1.31.2 # Apache-2.0

setup.cfg

@@ -53,14 +53,14 @@ oslo.policy.enforcer =
 
 console_scripts =
     designate-rootwrap = oslo_rootwrap.cmd:main
-    designate-api = designate.cmd.threading.api:main
-    designate-central = designate.cmd.threading.central:main
-    designate-manage = designate.cmd.threading.manage:main
-    designate-mdns = designate.cmd.threading.mdns:main
-    designate-sink = designate.cmd.threading.sink:main
-    designate-worker = designate.cmd.threading.worker:main
-    designate-producer = designate.cmd.threading.producer:main
-    designate-status = designate.cmd.threading.status:main
+    designate-api = designate.cmd.api:main
+    designate-central = designate.cmd.central:main
+    designate-manage = designate.cmd.manage:main
+    designate-mdns = designate.cmd.mdns:main
+    designate-sink = designate.cmd.sink:main
+    designate-worker = designate.cmd.worker:main
+    designate-producer = designate.cmd.producer:main
+    designate-status = designate.cmd.status:main
 
 designate.api.admin.extensions =
     reports = designate.api.admin.controllers.extensions.reports:ReportsController