fix: verify dedicated endpoint predict_async TLS against the certifi CA bundle

Endpoint.predict_async on dedicated endpoints used a bare aiohttp.ClientSession,
which verifies TLS against the system CA store and fails with
CERTIFICATE_VERIFY_FAILED in environments where that store is missing or
incomplete (e.g. containers). This builds an SSLContext from certifi (matching
the synchronous predict() path, which uses requests/certifi) so the async path
trusts the same CAs.

PiperOrigin-RevId: 927649578

Author: IronPan

google/cloud/aiplatform/models.py

@@ -2811,10 +2811,20 @@ async def predict_async(
             aiohttp.ClientTimeout(total=timeout) if timeout is not None else None
         )
 
+        # Verify TLS against certifi, like the sync path (requests). aiohttp
+        # otherwise uses the system CA store, which is often missing in
+        # containers and fails with CERTIFICATE_VERIFY_FAILED.
+        import ssl
+
+        import certifi
+
+        ssl_context = ssl.create_default_context(cafile=certifi.where())
+        connector = aiohttp.TCPConnector(ssl=ssl_context)
+
         # Use a per-call session so the underlying connector is always closed,
         # avoiding leaked ClientSessions (Python has no async destructor to do
         # this for a cached session).
-        async with aiohttp.ClientSession() as session:
+        async with aiohttp.ClientSession(connector=connector) as session:
             async with session.post(
                 url=url,
                 data=data,

setup.py

@@ -324,6 +324,7 @@
             " <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*"
         ),
         "google-auth >= 2.47.0, <3.0.0",
+        "certifi >= 2023.7.22",
         "proto-plus >= 1.22.3, <2.0.0",
         "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
         "packaging >= 14.3",

tests/unit/aiplatform/test_endpoints.py

@@ -19,6 +19,7 @@
 from datetime import datetime, timedelta
 from importlib import reload
 import json
+import ssl
 import aiohttp
 from aiohttp import web as aiohttp_web
 import requests
@@ -3809,6 +3810,34 @@ async def test_predict_async_dedicated_endpoint_closes_session(self):
 
         close_mock.assert_awaited_once()
 
+    @pytest.mark.asyncio
+    @pytest.mark.usefixtures(
+        "get_dedicated_endpoint_mock", "predict_endpoint_aiohttp_mock"
+    )
+    async def test_predict_async_dedicated_endpoint_verifies_certifi(self):
+        """The aiohttp session pins TLS verification to the certifi CA bundle.
+
+        Mirrors the synchronous predict() path (requests -> certifi), so the
+        async path does not fall back to the system CA store, which is commonly
+        missing in containers and raises CERTIFICATE_VERIFY_FAILED.
+        """
+        import certifi
+
+        test_endpoint = models.Endpoint(_TEST_ENDPOINT_NAME)
+
+        sentinel_context = ssl.create_default_context(cafile=certifi.where())
+        with mock.patch.object(
+            ssl, "create_default_context", return_value=sentinel_context
+        ) as create_context_mock, mock.patch.object(
+            aiohttp, "TCPConnector", wraps=aiohttp.TCPConnector
+        ) as connector_mock:
+            await test_endpoint.predict_async(
+                instances=_TEST_INSTANCES, parameters={"param": 3.0}
+            )
+
+        create_context_mock.assert_called_once_with(cafile=certifi.where())
+        connector_mock.assert_called_once_with(ssl=sentinel_context)
+
     @pytest.mark.asyncio
     @pytest.mark.usefixtures("get_dedicated_endpoint_mock")
     async def test_predict_async_dedicated_endpoint_integration(self):