[Misc] Manage HTTP connections in one place (#6600)

tests/conftest.py

@@ -16,6 +16,7 @@ from transformers import (AutoModelForCausalLM, AutoModelForVision2Seq,
 from vllm import LLM, SamplingParams
 from vllm.assets.image import ImageAsset
 from vllm.config import TokenizerPoolConfig
+from vllm.connections import global_http_connection
 from vllm.distributed import (destroy_distributed_environment,
                               destroy_model_parallel)
 from vllm.inputs import TextPrompt
@@ -74,6 +75,13 @@ IMAGE_ASSETS = _ImageAssets()
 """Singleton instance of :class:`_ImageAssets`."""
 
 
+@pytest.fixture(autouse=True)
+def init_test_http_connection():
+    # pytest_asyncio may use a different event loop per test
+    # so we need to make sure the async client is created anew
+    global_http_connection.reuse_client = False
+
+
 def cleanup():
     destroy_model_parallel()
     destroy_distributed_environment()