From f98efabf896298f8c7bd056112a7e16576442a43 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Mon, 7 Apr 2025 15:23:59 -0700
Subject: [PATCH 1/9] chore: add check for closed connector

---
 google/cloud/sql/connector/connector.py |  7 ++++
 tests/unit/test_connector.py            | 55 ++++++++++++++++++-------
 2 files changed, 46 insertions(+), 16 deletions(-)

diff --git a/google/cloud/sql/connector/connector.py b/google/cloud/sql/connector/connector.py
index 05eaa51df..2a81baff8 100755
--- a/google/cloud/sql/connector/connector.py
+++ b/google/cloud/sql/connector/connector.py
@@ -153,6 +153,7 @@ def __init__(
         # connection name string and enable_iam_auth boolean flag
         self._cache: dict[tuple[str, bool], MonitoredCache] = {}
         self._client: Optional[CloudSQLClient] = None
+        self._closed: bool = False
 
         # initialize credentials
         scopes = ["https://www.googleapis.com/auth/sqlservice.admin"]
@@ -279,7 +280,11 @@ async def connect_async(
                 and then subsequent attempt with IAM database authentication.
             KeyError: Unsupported database driver Must be one of pymysql, asyncpg,
                 pg8000, and pytds.
+            RuntimeError: Connector has been closed. Cannot connect using a closed
+                Connector.
         """
+        if self._closed:
+            raise RuntimeError("Cannot connect using a closed Connector.")
         if self._keys is None:
             self._keys = asyncio.create_task(generate_keys())
         if self._client is None:
@@ -462,6 +467,7 @@ def close(self) -> None:
                 self._loop.call_soon_threadsafe(self._loop.stop)
             # wait for thread to finish closing (i.e. loop to stop)
             self._thread.join()
+        self._closed = True
 
     async def close_async(self) -> None:
         """Helper function to cancel the cache's tasks
@@ -469,6 +475,7 @@ async def close_async(self) -> None:
         await asyncio.gather(*[cache.close() for cache in self._cache.values()])
         if self._client:
             await self._client.close()
+        self._closed = True
 
 
 async def create_async_connector(
diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index 157697723..e76c92281 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -1,19 +1,3 @@
-"""
-Copyright 2021 Google LLC
-
-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
-
-  https://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.
-"""
-
 import asyncio
 import os
 from typing import Union
@@ -468,3 +452,42 @@ def test_configured_quota_project_env_var(
         assert connector._quota_project == quota_project
     # unset env var
     del os.environ["GOOGLE_CLOUD_QUOTA_PROJECT"]
+
+
+@pytest.mark.asyncio
+async def test_connect_async_closed_connector(
+    fake_credentials: Credentials, fake_client: CloudSQLClient
+) -> None:
+    """Test that calling connect_async() on a closed connector raises an error."""
+    async with Connector(
+        credentials=fake_credentials, loop=asyncio.get_running_loop()
+    ) as connector:
+        connector._client = fake_client
+        await connector.close_async()
+        with pytest.raises(RuntimeError) as exc_info:
+            await connector.connect_async(
+                "test-project:test-region:test-instance",
+                "asyncpg",
+                user="my-user",
+                password="my-pass",
+                db="my-db",
+            )
+        assert exc_info.value.args[0] == "Cannot connect using a closed Connector."
+
+
+def test_connect_closed_connector(
+    fake_credentials: Credentials, fake_client: CloudSQLClient
+) -> None:
+    """Test that calling connect() on a closed connector raises an error."""
+    with Connector(credentials=fake_credentials) as connector:
+        connector._client = fake_client
+        connector.close()
+        with pytest.raises(RuntimeError) as exc_info:
+            connector.connect(
+                "test-project:test-region:test-instance",
+                "pg8000",
+                user="my-user",
+                password="my-pass",
+                db="my-db",
+            )
+        assert exc_info.value.args[0] == "Cannot connect using a closed Connector."

From ad46fd7f011937d46ca5d479ab8ec0216bd5e490 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Mon, 7 Apr 2025 15:30:28 -0700
Subject: [PATCH 2/9] chore: add header back to the test_connector.py

---
 tests/unit/test_connector.py | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index e76c92281..544940662 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -1,3 +1,19 @@
+"""
+Copyright 2021 Google LLC
+
+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
+
+  https://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.
+"""
+
 import asyncio
 import os
 from typing import Union

From 7799b12fe60f68cbc0ab32b0a65cd8dd38f3e2c3 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Mon, 7 Apr 2025 15:44:44 -0700
Subject: [PATCH 3/9] chore: add await in aync connector test

---
 tests/unit/test_connector.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index 544940662..1bbe62013 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -480,6 +480,8 @@ async def test_connect_async_closed_connector(
     ) as connector:
         connector._client = fake_client
         await connector.close_async()
+        # wait for close to complete
+        await asyncio.sleep(0.1)
         with pytest.raises(RuntimeError) as exc_info:
             await connector.connect_async(
                 "test-project:test-region:test-instance",

From b1e046b981bcbb63fac5c9ec2bc15681438592dc Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Mon, 7 Apr 2025 15:56:48 -0700
Subject: [PATCH 4/9] chore: try adding time.sleep for sync closed connector

---
 tests/unit/test_connector.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index 1bbe62013..ed8683dd6 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -16,6 +16,7 @@
 
 import asyncio
 import os
+import time
 from typing import Union
 
 from aiohttp import ClientResponseError
@@ -500,6 +501,7 @@ def test_connect_closed_connector(
     with Connector(credentials=fake_credentials) as connector:
         connector._client = fake_client
         connector.close()
+        time.sleep(0.1)
         with pytest.raises(RuntimeError) as exc_info:
             connector.connect(
                 "test-project:test-region:test-instance",

From 9a192a4804e6cd415c454195caab808a1e4254c7 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Tue, 15 Apr 2025 12:31:00 -0700
Subject: [PATCH 5/9] chore: update closed conn tests

---
 google/cloud/sql/connector/connector.py | 1 -
 tests/unit/test_connector.py            | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/google/cloud/sql/connector/connector.py b/google/cloud/sql/connector/connector.py
index 2a81baff8..636a87a90 100755
--- a/google/cloud/sql/connector/connector.py
+++ b/google/cloud/sql/connector/connector.py
@@ -467,7 +467,6 @@ def close(self) -> None:
                 self._loop.call_soon_threadsafe(self._loop.stop)
             # wait for thread to finish closing (i.e. loop to stop)
             self._thread.join()
-        self._closed = True
 
     async def close_async(self) -> None:
         """Helper function to cancel the cache's tasks
diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index ed8683dd6..89b9e909f 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -501,7 +501,7 @@ def test_connect_closed_connector(
     with Connector(credentials=fake_credentials) as connector:
         connector._client = fake_client
         connector.close()
-        time.sleep(0.1)
+        time.sleep(3.1)
         with pytest.raises(RuntimeError) as exc_info:
             connector.connect(
                 "test-project:test-region:test-instance",

From 27c2da800d31fb534653f03e53b8721761d4899e Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Fri, 16 May 2025 14:59:51 -0700
Subject: [PATCH 6/9] chore: update _closed internal variable in connect
 function

---
 google/cloud/sql/connector/connector.py | 3 +++
 tests/unit/test_connector.py            | 4 ++--
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/google/cloud/sql/connector/connector.py b/google/cloud/sql/connector/connector.py
index 636a87a90..adb8d4474 100755
--- a/google/cloud/sql/connector/connector.py
+++ b/google/cloud/sql/connector/connector.py
@@ -243,6 +243,8 @@ def connect(
         # connect runs sync database connections on background thread.
         # Async database connections should call 'connect_async' directly to
         # avoid hanging indefinitely.
+        if self._closed:
+            raise RuntimeError("Cannot connect using a closed Connector.")
         connect_future = asyncio.run_coroutine_threadsafe(
             self.connect_async(instance_connection_string, driver, **kwargs),
             self._loop,
@@ -467,6 +469,7 @@ def close(self) -> None:
                 self._loop.call_soon_threadsafe(self._loop.stop)
             # wait for thread to finish closing (i.e. loop to stop)
             self._thread.join()
+        self._closed = True
 
     async def close_async(self) -> None:
         """Helper function to cancel the cache's tasks
diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index 89b9e909f..cd4746d3e 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -482,7 +482,7 @@ async def test_connect_async_closed_connector(
         connector._client = fake_client
         await connector.close_async()
         # wait for close to complete
-        await asyncio.sleep(0.1)
+        # await asyncio.sleep(0.1)
         with pytest.raises(RuntimeError) as exc_info:
             await connector.connect_async(
                 "test-project:test-region:test-instance",
@@ -501,7 +501,7 @@ def test_connect_closed_connector(
     with Connector(credentials=fake_credentials) as connector:
         connector._client = fake_client
         connector.close()
-        time.sleep(3.1)
+        # time.sleep(3.1)
         with pytest.raises(RuntimeError) as exc_info:
             connector.connect(
                 "test-project:test-region:test-instance",

From e76133f0f7b84dccbf947bfbf250f7324201dfc2 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Fri, 16 May 2025 15:25:03 -0700
Subject: [PATCH 7/9] chore: update exception type and exception message

---
 google/cloud/sql/connector/connector.py  | 11 +++++++++--
 google/cloud/sql/connector/exceptions.py |  7 +++++++
 tests/unit/test_connector.py             | 19 +++++++++++--------
 3 files changed, 27 insertions(+), 10 deletions(-)

diff --git a/google/cloud/sql/connector/connector.py b/google/cloud/sql/connector/connector.py
index adb8d4474..a674f25b6 100755
--- a/google/cloud/sql/connector/connector.py
+++ b/google/cloud/sql/connector/connector.py
@@ -43,6 +43,7 @@
 from google.cloud.sql.connector.resolver import DnsResolver
 from google.cloud.sql.connector.utils import format_database_user
 from google.cloud.sql.connector.utils import generate_keys
+from google.cloud.sql.connector.exceptions import ClosedConnectorError
 
 logger = logging.getLogger(name=__name__)
 
@@ -243,8 +244,12 @@ def connect(
         # connect runs sync database connections on background thread.
         # Async database connections should call 'connect_async' directly to
         # avoid hanging indefinitely.
+
+        # Check if the connector is closed before attempting to connect.
         if self._closed:
-            raise RuntimeError("Cannot connect using a closed Connector.")
+            raise ClosedConnectorError(
+                "Connection attempt failed because the connector has already been closed."
+            )
         connect_future = asyncio.run_coroutine_threadsafe(
             self.connect_async(instance_connection_string, driver, **kwargs),
             self._loop,
@@ -286,7 +291,9 @@ async def connect_async(
                 Connector.
         """
         if self._closed:
-            raise RuntimeError("Cannot connect using a closed Connector.")
+            raise ClosedConnectorError(
+                "Connection attempt failed because the connector has already been closed."
+            )
         if self._keys is None:
             self._keys = asyncio.create_task(generate_keys())
         if self._client is None:
diff --git a/google/cloud/sql/connector/exceptions.py b/google/cloud/sql/connector/exceptions.py
index da39ea25d..1f15ced47 100644
--- a/google/cloud/sql/connector/exceptions.py
+++ b/google/cloud/sql/connector/exceptions.py
@@ -84,3 +84,10 @@ class CacheClosedError(Exception):
     Exception to be raised when a ConnectionInfoCache can not be accessed after
     it is closed.
     """
+
+
+class ClosedConnectorError(Exception):
+    """
+    Exception to be raised when a Connector is closed and connect method is
+    called on it.
+    """
diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index cd4746d3e..8889bafa2 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -16,7 +16,6 @@
 
 import asyncio
 import os
-import time
 from typing import Union
 
 from aiohttp import ClientResponseError
@@ -31,6 +30,7 @@
 from google.cloud.sql.connector.connection_name import ConnectionName
 from google.cloud.sql.connector.exceptions import CloudSQLIPTypeError
 from google.cloud.sql.connector.exceptions import IncompatibleDriverError
+from google.cloud.sql.connector.exceptions import ClosedConnectionError
 from google.cloud.sql.connector.instance import RefreshAheadCache
 
 
@@ -481,9 +481,7 @@ async def test_connect_async_closed_connector(
     ) as connector:
         connector._client = fake_client
         await connector.close_async()
-        # wait for close to complete
-        # await asyncio.sleep(0.1)
-        with pytest.raises(RuntimeError) as exc_info:
+        with pytest.raises(ClosedConnectionError) as exc_info:
             await connector.connect_async(
                 "test-project:test-region:test-instance",
                 "asyncpg",
@@ -491,7 +489,10 @@ async def test_connect_async_closed_connector(
                 password="my-pass",
                 db="my-db",
             )
-        assert exc_info.value.args[0] == "Cannot connect using a closed Connector."
+        assert (
+            exc_info.value.args[0]
+            == "Connection attempt failed because the connector has already been closed."
+        )
 
 
 def test_connect_closed_connector(
@@ -501,8 +502,7 @@ def test_connect_closed_connector(
     with Connector(credentials=fake_credentials) as connector:
         connector._client = fake_client
         connector.close()
-        # time.sleep(3.1)
-        with pytest.raises(RuntimeError) as exc_info:
+        with pytest.raises(ClosedConnectionError) as exc_info:
             connector.connect(
                 "test-project:test-region:test-instance",
                 "pg8000",
@@ -510,4 +510,7 @@ def test_connect_closed_connector(
                 password="my-pass",
                 db="my-db",
             )
-        assert exc_info.value.args[0] == "Cannot connect using a closed Connector."
+        assert (
+            exc_info.value.args[0]
+            == "Connection attempt failed because the connector has already been closed."
+        )

From b8bc9120bbc6005c55decbadffd3c8d0a0beb100 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Fri, 16 May 2025 15:31:02 -0700
Subject: [PATCH 8/9] chore: update import statements

---
 google/cloud/sql/connector/connector.py | 2 +-
 tests/unit/test_connector.py            | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/google/cloud/sql/connector/connector.py b/google/cloud/sql/connector/connector.py
index a674f25b6..df519cd41 100755
--- a/google/cloud/sql/connector/connector.py
+++ b/google/cloud/sql/connector/connector.py
@@ -33,6 +33,7 @@
 from google.cloud.sql.connector.enums import DriverMapping
 from google.cloud.sql.connector.enums import IPTypes
 from google.cloud.sql.connector.enums import RefreshStrategy
+from google.cloud.sql.connector.exceptions import ClosedConnectorError
 from google.cloud.sql.connector.instance import RefreshAheadCache
 from google.cloud.sql.connector.lazy import LazyRefreshCache
 from google.cloud.sql.connector.monitored_cache import MonitoredCache
@@ -43,7 +44,6 @@
 from google.cloud.sql.connector.resolver import DnsResolver
 from google.cloud.sql.connector.utils import format_database_user
 from google.cloud.sql.connector.utils import generate_keys
-from google.cloud.sql.connector.exceptions import ClosedConnectorError
 
 logger = logging.getLogger(name=__name__)
 
diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index 8889bafa2..e943eae0d 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -29,8 +29,8 @@
 from google.cloud.sql.connector.client import CloudSQLClient
 from google.cloud.sql.connector.connection_name import ConnectionName
 from google.cloud.sql.connector.exceptions import CloudSQLIPTypeError
+from google.cloud.sql.connector.exceptions import ClosedConnectorError
 from google.cloud.sql.connector.exceptions import IncompatibleDriverError
-from google.cloud.sql.connector.exceptions import ClosedConnectionError
 from google.cloud.sql.connector.instance import RefreshAheadCache
 
 
@@ -481,7 +481,7 @@ async def test_connect_async_closed_connector(
     ) as connector:
         connector._client = fake_client
         await connector.close_async()
-        with pytest.raises(ClosedConnectionError) as exc_info:
+        with pytest.raises(ClosedConnectorError) as exc_info:
             await connector.connect_async(
                 "test-project:test-region:test-instance",
                 "asyncpg",
@@ -502,7 +502,7 @@ def test_connect_closed_connector(
     with Connector(credentials=fake_credentials) as connector:
         connector._client = fake_client
         connector.close()
-        with pytest.raises(ClosedConnectionError) as exc_info:
+        with pytest.raises(ClosedConnectorError) as exc_info:
             connector.connect(
                 "test-project:test-region:test-instance",
                 "pg8000",

From e1f3d4ff076c90eef89ba5c9aadc4cd8f8b15288 Mon Sep 17 00:00:00 2001
From: kgala2 <galakp@google.com>
Date: Fri, 16 May 2025 16:15:13 -0700
Subject: [PATCH 9/9] chore: reorder imports in test file

---
 tests/unit/test_connector.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/unit/test_connector.py b/tests/unit/test_connector.py
index e943eae0d..bde7f65a9 100644
--- a/tests/unit/test_connector.py
+++ b/tests/unit/test_connector.py
@@ -28,8 +28,8 @@
 from google.cloud.sql.connector import IPTypes
 from google.cloud.sql.connector.client import CloudSQLClient
 from google.cloud.sql.connector.connection_name import ConnectionName
-from google.cloud.sql.connector.exceptions import CloudSQLIPTypeError
 from google.cloud.sql.connector.exceptions import ClosedConnectorError
+from google.cloud.sql.connector.exceptions import CloudSQLIPTypeError
 from google.cloud.sql.connector.exceptions import IncompatibleDriverError
 from google.cloud.sql.connector.instance import RefreshAheadCache