Add AIOHttpConnection and [async] extra

dev-requirements.txt

@@ -14,3 +14,8 @@ pandas
 pyyaml<5.3
 
 black; python_version>="3.6"
+
+# Requirements for testing [async] extra
+aiohttp; python_version>="3.6"
+pytest-asyncio; python_version>="3.6"
+unasync; python_version>="3.6"

elasticsearch/__init__.py

@@ -9,6 +9,7 @@
 __version__ = VERSION
 __versionstr__ = ".".join(map(str, VERSION))
 
+import sys
 import logging
 import warnings
 
@@ -64,3 +65,16 @@
     "AuthorizationException",
     "ElasticsearchDeprecationWarning",
 ]
+
+try:
+    # Asyncio only supported on Python 3.6+
+    if sys.version_info < (3, 6):
+        raise ImportError
+
+    from ._async.http_aiohttp import AIOHttpConnection
+    from ._async.transport import AsyncTransport
+    from ._async.client import AsyncElasticsearch
+
+    __all__ += ["AIOHttpConnection", "AsyncTransport", "AsyncElasticsearch"]
+except (ImportError, SyntaxError):
+    pass

elasticsearch/_async/__init__.py

@@ -0,0 +1,3 @@
+# Licensed to Elasticsearch B.V under one or more agreements.
+# Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+# See the LICENSE file in the project root for more information