fix: guard against missing _async_httpx_client in aclose()

[jrcks67]

Problem

When BaseApiClient.__init__ raises before _async_httpx_client is assigned (e.g. an auth error thrown before any HTTP call is made), __del__ still schedules aclose() as an asyncio task. That task then crashes with:

AttributeError: 'BaseApiClient' object has no attribute '_async_httpx_client'
Task exception was never retrieved
future: <Task finished name='Task-...' coro=<BaseApiClient.aclose()> exception=AttributeError(...)>

The exception surfaces as an unhandled asyncio task exception — swallowed silently in production unless PYTHONASYNCIODEBUG=1 is set, making it hard to spot.

Minimal repro (v1.66.0)

import asyncio, os
os.environ.pop("GOOGLE_API_KEY", None)
from google import genai
client = genai.Client(api_key="")
# trigger any async call — the __del__ task fires after GC and crashes
asyncio.run(client.aio.models.generate_content("gemini-2.0-flash", contents="hi"))

Traceback:

Task exception was never retrieved
future: <Task finished name='Task-18' coro=<BaseApiClient.aclose() done, defined at .../google/genai/_api_client.py:2100> exception=AttributeError("'BaseApiClient' object has no attribute '_async_httpx_client'")>
  File ".../google/genai/_api_client.py", line 2105, in aclose
    await self._async_httpx_client.aclose()
AttributeError: 'BaseApiClient' object has no attribute '_async_httpx_client'

Fix

close() already guards the equivalent sync path with and self._httpx_client. Apply the same pattern to aclose() using getattr(..., None) to safely handle the case where _async_httpx_client was never set:

# before
if not self._http_options.httpx_async_client:
    await self._async_httpx_client.aclose()

# after
if not self._http_options.httpx_async_client and getattr(self, '_async_httpx_client', None):
    await self._async_httpx_client.aclose()

One-line change, no behaviour difference in the normal path.

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[Venkaiahbabuneelam]

Hi @jrcks67, Thanks for reaching out us!

It looks like some checks failed. Kindly resolve the conflicts.

Thanks