PYTHON-5100 Convert test.test_server_selection to async (#2120)

test/asynchronous/test_server_selection.py

@@ -0,0 +1,211 @@
+# Copyright 2015-present MongoDB, Inc.
+#
+# 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.
+
+"""Test the topology module's Server Selection Spec implementation."""
+from __future__ import annotations
+
+import os
+import sys
+from pathlib import Path
+
+from pymongo import AsyncMongoClient, ReadPreference
+from pymongo.asynchronous.settings import TopologySettings
+from pymongo.asynchronous.topology import Topology
+from pymongo.errors import ServerSelectionTimeoutError
+from pymongo.hello import HelloCompat
+from pymongo.operations import _Op
+from pymongo.server_selectors import writable_server_selector
+from pymongo.typings import strip_optional
+
+sys.path[0:0] = [""]
+
+from test.asynchronous import AsyncIntegrationTest, async_client_context, unittest
+from test.asynchronous.utils_selection_tests import (
+    create_selection_tests,
+    get_addresses,
+    get_topology_settings_dict,
+    make_server_description,
+)
+from test.utils import (
+    EventListener,
+    FunctionCallRecorder,
+    OvertCommandListener,
+    async_wait_until,
+)
+
+_IS_SYNC = False
+
+# Location of JSON test specifications.
+if _IS_SYNC:
+    TEST_PATH = os.path.join(
+        Path(__file__).resolve().parent, "server_selection", "server_selection"
+    )
+else:
+    TEST_PATH = os.path.join(
+        Path(__file__).resolve().parent.parent, "server_selection", "server_selection"
+    )
+
+
+class SelectionStoreSelector:
+    """No-op selector that keeps track of what was passed to it."""
+
+    def __init__(self):
+        self.selection = None
+
+    def __call__(self, selection):
+        self.selection = selection
+        return selection
+
+
+class TestAllScenarios(create_selection_tests(TEST_PATH)):  # type: ignore
+    pass
+
+
+class TestCustomServerSelectorFunction(AsyncIntegrationTest):
+    @async_client_context.require_replica_set
+    async def test_functional_select_max_port_number_host(self):
+        # Selector that returns server with highest port number.
+        def custom_selector(servers):
+            ports = [s.address[1] for s in servers]
+            idx = ports.index(max(ports))
+            return [servers[idx]]
+
+        # Initialize client with appropriate listeners.
+        listener = OvertCommandListener()
+        client = await self.async_rs_or_single_client(
+            server_selector=custom_selector, event_listeners=[listener]
+        )
+        coll = client.get_database("testdb", read_preference=ReadPreference.NEAREST).coll
+        self.addAsyncCleanup(client.drop_database, "testdb")
+
+        # Wait the node list to be fully populated.
+        async def all_hosts_started():
+            return len((await client.admin.command(HelloCompat.LEGACY_CMD))["hosts"]) == len(
+                client._topology._description.readable_servers
+            )
+
+        await async_wait_until(all_hosts_started, "receive heartbeat from all hosts")
+
+        expected_port = max(
+            [strip_optional(n.address[1]) for n in client._topology._description.readable_servers]
+        )
+
+        # Insert 1 record and access it 10 times.
+        await coll.insert_one({"name": "John Doe"})
+        for _ in range(10):
+            await coll.find_one({"name": "John Doe"})
+
+        # Confirm all find commands are run against appropriate host.
+        for command in listener.started_events:
+            if command.command_name == "find":
+                self.assertEqual(command.connection_id[1], expected_port)
+
+    async def test_invalid_server_selector(self):
+        # Client initialization must fail if server_selector is not callable.
+        for selector_candidate in [[], 10, "string", {}]:
+            with self.assertRaisesRegex(ValueError, "must be a callable"):
+                AsyncMongoClient(connect=False, server_selector=selector_candidate)
+
+        # None value for server_selector is OK.
+        AsyncMongoClient(connect=False, server_selector=None)
+
+    @async_client_context.require_replica_set
+    async def test_selector_called(self):
+        selector = FunctionCallRecorder(lambda x: x)
+
+        # Client setup.
+        mongo_client = await self.async_rs_or_single_client(server_selector=selector)
+        test_collection = mongo_client.testdb.test_collection
+        self.addAsyncCleanup(mongo_client.drop_database, "testdb")
+
+        # Do N operations and test selector is called at least N times.
+        await test_collection.insert_one({"age": 20, "name": "John"})
+        await test_collection.insert_one({"age": 31, "name": "Jane"})
+        await test_collection.update_one({"name": "Jane"}, {"$set": {"age": 21}})
+        await test_collection.find_one({"name": "Roe"})
+        self.assertGreaterEqual(selector.call_count, 4)
+
+    @async_client_context.require_replica_set
+    async def test_latency_threshold_application(self):
+        selector = SelectionStoreSelector()
+
+        scenario_def: dict = {
+            "topology_description": {
+                "type": "ReplicaSetWithPrimary",
+                "servers": [
+                    {"address": "b:27017", "avg_rtt_ms": 10000, "type": "RSSecondary", "tag": {}},
+                    {"address": "c:27017", "avg_rtt_ms": 20000, "type": "RSSecondary", "tag": {}},
+                    {"address": "a:27017", "avg_rtt_ms": 30000, "type": "RSPrimary", "tag": {}},
+                ],
+            }
+        }
+
+        # Create & populate Topology such that all but one server is too slow.
+        rtt_times = [srv["avg_rtt_ms"] for srv in scenario_def["topology_description"]["servers"]]
+        min_rtt_idx = rtt_times.index(min(rtt_times))
+        seeds, hosts = get_addresses(scenario_def["topology_description"]["servers"])
+        settings = get_topology_settings_dict(
+            heartbeat_frequency=1, local_threshold_ms=1, seeds=seeds, server_selector=selector
+        )
+        topology = Topology(TopologySettings(**settings))
+        await topology.open()
+        for server in scenario_def["topology_description"]["servers"]:
+            server_description = make_server_description(server, hosts)
+            await topology.on_change(server_description)
+
+        # Invoke server selection and assert no filtering based on latency
+        # prior to custom server selection logic kicking in.
+        server = await topology.select_server(ReadPreference.NEAREST, _Op.TEST)
+        assert selector.selection is not None
+        self.assertEqual(len(selector.selection), len(topology.description.server_descriptions()))
+
+        # Ensure proper filtering based on latency after custom selection.
+        self.assertEqual(server.description.address, seeds[min_rtt_idx])
+
+    @async_client_context.require_replica_set
+    async def test_server_selector_bypassed(self):
+        selector = FunctionCallRecorder(lambda x: x)
+
+        scenario_def = {
+            "topology_description": {
+                "type": "ReplicaSetNoPrimary",
+                "servers": [
+                    {"address": "b:27017", "avg_rtt_ms": 10000, "type": "RSSecondary", "tag": {}},
+                    {"address": "c:27017", "avg_rtt_ms": 20000, "type": "RSSecondary", "tag": {}},
+                    {"address": "a:27017", "avg_rtt_ms": 30000, "type": "RSSecondary", "tag": {}},
+                ],
+            }
+        }
+
+        # Create & populate Topology such that no server is writeable.
+        seeds, hosts = get_addresses(scenario_def["topology_description"]["servers"])
+        settings = get_topology_settings_dict(
+            heartbeat_frequency=1, local_threshold_ms=1, seeds=seeds, server_selector=selector
+        )
+        topology = Topology(TopologySettings(**settings))
+        await topology.open()
+        for server in scenario_def["topology_description"]["servers"]:
+            server_description = make_server_description(server, hosts)
+            await topology.on_change(server_description)
+
+        # Invoke server selection and assert no calls to our custom selector.
+        with self.assertRaisesRegex(ServerSelectionTimeoutError, "No primary available for writes"):
+            await topology.select_server(
+                writable_server_selector, _Op.TEST, server_selection_timeout=0.1
+            )
+        self.assertEqual(selector.call_count, 0)
+
+
+if __name__ == "__main__":
+    unittest.main()

test/test_server_selection.py

@@ -17,6 +17,7 @@
 
 import os
 import sys
+from pathlib import Path
 
 from pymongo import MongoClient, ReadPreference
 from pymongo.errors import ServerSelectionTimeoutError
@@ -43,11 +44,17 @@
     make_server_description,
 )
 
+_IS_SYNC = True
+
 # Location of JSON test specifications.
-_TEST_PATH = os.path.join(
-    os.path.dirname(os.path.realpath(__file__)),
-    os.path.join("server_selection", "server_selection"),
-)
+if _IS_SYNC:
+    TEST_PATH = os.path.join(
+        Path(__file__).resolve().parent, "server_selection", "server_selection"
+    )
+else:
+    TEST_PATH = os.path.join(
+        Path(__file__).resolve().parent.parent, "server_selection", "server_selection"
+    )
 
 
 class SelectionStoreSelector:
@@ -61,7 +68,7 @@ def __call__(self, selection):
         return selection
 
 
-class TestAllScenarios(create_selection_tests(_TEST_PATH)):  # type: ignore
+class TestAllScenarios(create_selection_tests(TEST_PATH)):  # type: ignore
     pass
 
 
@@ -79,13 +86,12 @@ def custom_selector(servers):
         client = self.rs_or_single_client(
             server_selector=custom_selector, event_listeners=[listener]
         )
-        self.addCleanup(client.close)
         coll = client.get_database("testdb", read_preference=ReadPreference.NEAREST).coll
         self.addCleanup(client.drop_database, "testdb")
 
         # Wait the node list to be fully populated.
         def all_hosts_started():
-            return len(client.admin.command(HelloCompat.LEGACY_CMD)["hosts"]) == len(
+            return len((client.admin.command(HelloCompat.LEGACY_CMD))["hosts"]) == len(
                 client._topology._description.readable_servers
             )
 
@@ -121,7 +127,6 @@ def test_selector_called(self):
         # Client setup.
         mongo_client = self.rs_or_single_client(server_selector=selector)
         test_collection = mongo_client.testdb.test_collection
-        self.addCleanup(mongo_client.close)
         self.addCleanup(mongo_client.drop_database, "testdb")
 
         # Do N operations and test selector is called at least N times.

tools/synchro.py

@@ -236,10 +236,11 @@ def async_only_test(f: str) -> bool:
     "test_retryable_writes_unified.py",
     "test_run_command.py",
     "test_sdam_monitoring_spec.py",
+    "test_server_selection.py",
     "test_server_selection_in_window.py",
     "test_server_selection_logging.py",
-    "test_session.py",
     "test_server_selection_rtt.py",
+    "test_session.py",
     "test_sessions_unified.py",
     "test_srv_polling.py",
     "test_ssl.py",