add test for repr and change changelog

Author: sleepyStick

doc/changelog.rst

@@ -9,6 +9,8 @@ PyMongo 4.12 brings a number of changes including:
 - Support for configuring DEK cache lifetime via the ``key_expiration_ms`` argument to
   :class:`~pymongo.encryption_options.AutoEncryptionOpts`.
 - Support for $lookup in CSFLE and QE supported on MongoDB 8.1+.
+- AsyncMongoClient no longer performs dns resolution for "mongodb+srv://" connection string in the constructor.
+  To avoid blocking the asyncio loop, the resolution is now deferred until the client is first connected.
 
 Issues Resolved
 ...............

pymongo/asynchronous/mongo_client.py

@@ -1255,7 +1255,7 @@ def option_repr(option: str, value: Any) -> str:
 
         # Host first...
         if self._topology is None:
-            options = self._resolve_srv_info["seeds"]
+            options = [f"host='mongodb+srv://{self._resolve_srv_info['fqdn']}'"]
         else:
             options = [
                 "host=%r"

pymongo/synchronous/mongo_client.py

@@ -1253,7 +1253,7 @@ def option_repr(option: str, value: Any) -> str:
 
         # Host first...
         if self._topology is None:
-            options = self._resolve_srv_info["seeds"]
+            options = [f"host='mongodb+srv://{self._resolve_srv_info['fqdn']}'"]
         else:
             options = [
                 "host=%r"

test/asynchronous/test_client.py

@@ -933,6 +933,15 @@ async def test_repr(self):
         async with eval(the_repr) as client_two:
             self.assertEqual(client_two, client)
 
+    async def test_repr_srv_host(self):
+        client = AsyncMongoClient("mongodb+srv://test1.test.build.10gen.cc/")
+        # before srv resolution
+        self.assertIn("host='mongodb+srv://test1.test.build.10gen.cc'", repr(client))
+        await client.aconnect()
+        # after srv resolution
+        self.assertIn("host=['localhost.test.build.10gen.cc:", repr(client))
+        await client.close()
+
     async def test_getters(self):
         await async_wait_until(
             lambda: async_client_context.nodes == self.client.nodes, "find all nodes"

test/test_client.py

@@ -908,6 +908,15 @@ def test_repr(self):
         with eval(the_repr) as client_two:
             self.assertEqual(client_two, client)
 
+    def test_repr_srv_host(self):
+        client = MongoClient("mongodb+srv://test1.test.build.10gen.cc/")
+        # before srv resolution
+        self.assertIn("host='mongodb+srv://test1.test.build.10gen.cc'", repr(client))
+        client._connect()
+        # after srv resolution
+        self.assertIn("host=['localhost.test.build.10gen.cc:", repr(client))
+        client.close()
+
     def test_getters(self):
         wait_until(lambda: client_context.nodes == self.client.nodes, "find all nodes")