feat: restructure default client supplier to pass through config to cache rather than accepting a cache

Author: mattsb42-aws

src/aws_encryption_sdk/keyrings/aws_kms/client_cache.py

@@ -16,8 +16,6 @@
 from botocore.exceptions import BotoCoreError
 from botocore.session import Session as BotocoreSession
 
-from aws_encryption_sdk.identifiers import USER_AGENT_SUFFIX
-
 try:  # Python 3.5.0 and 3.5.1 have incompatible typing modules
     from typing import Dict  # noqa pylint: disable=unused-import
 except ImportError:  # pragma: no cover
@@ -36,17 +34,14 @@ class ClientCache(object):
 
     .. versionadded:: 1.5.0
 
-    :param botocore_session: Botocore session to use when creating clients (optional)
+    :param botocore_session: Botocore session to use when creating clients
     :type botocore_session: botocore.session.Session
     :param client_config: Config to use when creating client
     :type client_config: botocore.config.Config
     """
 
-    _botocore_session = attr.ib(default=attr.Factory(BotocoreSession), validator=instance_of(BotocoreSession))
-    _client_config = attr.ib(
-        default=attr.Factory(functools.partial(BotocoreConfig, user_agent_extra=USER_AGENT_SUFFIX)),
-        validator=instance_of(BotocoreConfig),
-    )
+    _botocore_session = attr.ib(validator=instance_of(BotocoreSession))
+    _client_config = attr.ib(validator=instance_of(BotocoreConfig))
 
     def __attrs_post_init__(self):
         """Set up internal cache."""

src/aws_encryption_sdk/keyrings/aws_kms/client_suppliers.py

@@ -5,14 +5,18 @@
 .. versionadded:: 1.5.0
 
 """
+import functools
 import logging
 
 import attr
 import six
 from attr.validators import deep_iterable, instance_of, is_callable, optional
 from botocore.client import BaseClient
+from botocore.config import Config as BotocoreConfig
+from botocore.session import Session as BotocoreSession
 
 from aws_encryption_sdk.exceptions import UnknownRegionError
+from aws_encryption_sdk.identifiers import USER_AGENT_SUFFIX
 from aws_encryption_sdk.internal.validators import value_is_not_a_string
 
 from .client_cache import ClientCache
@@ -58,11 +62,36 @@ class DefaultClientSupplier(ClientSupplier):
 
     .. versionadded:: 1.5.0
 
-    :param botocore_session: botocore session to use when creating clients (optional)
+    If you want clients to have special credentials or other configuration,
+    you can provide those with custom ``botocore`` Session and/or `Config`_ instances.
+
+    .. _Config: https://botocore.amazonaws.com/v1/documentation/api/latest/reference/config.html
+
+    .. code-block:: python
+
+        from aws_encryption_sdk.keyrings.aws_kms.client_supplier import DefaultClientSupplier
+        from botocore.session import Session
+        from botocore.config import Config
+
+        my_client_supplier = DefaultClientSupplier(
+            botocore_session=Session(**_get_custom_credentials()),
+            client_config=Config(connect_timeout=10),
+        )
+
+    :param botocore_session: Botocore session to use when creating clients (optional)
     :type botocore_session: botocore.session.Session
+    :param client_config: Config to use when creating client (optional)
+    :type client_config: botocore.config.Config
     """
 
-    _client_cache = attr.ib(default=attr.Factory(ClientCache), validator=instance_of(ClientCache))
+    _botocore_session = attr.ib(default=attr.Factory(BotocoreSession), validator=instance_of(BotocoreSession))
+    _client_config = attr.ib(
+        default=attr.Factory(functools.partial(BotocoreConfig, user_agent_extra=USER_AGENT_SUFFIX)),
+        validator=instance_of(BotocoreConfig),
+    )
+
+    def __attrs_post_init__(self):
+        self._client_cache = ClientCache(botocore_session=self._botocore_session, client_config=self._client_config)
 
     def __call__(self, region_name):
         # type: (Union[None, str]) -> BaseClient

test/functional/keyrings/aws_kms/test_client_cache.py

@@ -2,14 +2,16 @@
 # SPDX-License-Identifier: Apache-2.0
 """Functional tests for ``aws_encryption_sdk.keyrings.aws_kms.client_cache``."""
 import pytest
+from botocore.config import Config
+from botocore.session import Session
 
 from aws_encryption_sdk.keyrings.aws_kms.client_cache import ClientCache
 
 pytestmark = [pytest.mark.functional, pytest.mark.local]
 
 
 def test_client_cache_caches_clients():
-    cache = ClientCache()
+    cache = ClientCache(botocore_session=Session(), client_config=Config())
 
     initial_client = cache.client("us-west-2", "kms")
 
@@ -20,7 +22,7 @@ def test_client_cache_caches_clients():
 
 
 def test_client_cache_new_client():
-    cache = ClientCache()
+    cache = ClientCache(botocore_session=Session(), client_config=Config())
 
     initial_client = cache.client("us-west-2", "kms")
 

test/functional/keyrings/aws_kms/test_client_suppliers.py

@@ -2,6 +2,8 @@
 # SPDX-License-Identifier: Apache-2.0
 """Functional tests for ``aws_encryption_sdk.keyrings.aws_kms.client_suppliers``."""
 import pytest
+from botocore.config import Config
+from botocore.session import Session
 
 from aws_encryption_sdk.exceptions import UnknownRegionError
 from aws_encryption_sdk.keyrings.aws_kms.client_suppliers import (
@@ -34,6 +36,16 @@ def test_default_supplier_uses_cache():
     assert test is expected
 
 
+def test_default_supplier_passes_through_configs():
+    session = Session()
+    config = Config()
+
+    test = DefaultClientSupplier(botocore_session=session, client_config=config)
+
+    assert test._client_cache._botocore_session is session
+    assert test._client_cache._client_config is config
+
+
 @pytest.mark.parametrize(
     "kwargs",
     (

test/integration/keyrings/aws_kms/test_client_cache.py

@@ -2,6 +2,7 @@
 # SPDX-License-Identifier: Apache-2.0
 """Integration tests for ``aws_encryption_sdk.keyrings.aws_kms.client_cache``."""
 import pytest
+from botocore.config import Config
 from botocore.exceptions import BotoCoreError
 from botocore.session import Session
 
@@ -11,7 +12,7 @@
 
 
 def test_client_cache_removes_bad_client():
-    cache = ClientCache()
+    cache = ClientCache(botocore_session=Session(), client_config=Config())
     fake_region = "us-fake-1"
 
     initial_client = cache.client(fake_region, "kms")
@@ -25,7 +26,7 @@ def test_client_cache_removes_bad_client():
 
 
 def test_regional_client_does_not_modify_botocore_session():
-    cache = ClientCache(botocore_session=Session())
+    cache = ClientCache(botocore_session=Session(), client_config=Config())
     fake_region = "us-fake-1"
 
     assert cache._botocore_session.get_config_variable("region") != fake_region
@@ -34,7 +35,7 @@ def test_regional_client_does_not_modify_botocore_session():
 
 
 def test_client_cache_remove_bad_client_when_already_removed():
-    cache = ClientCache()
+    cache = ClientCache(botocore_session=Session(), client_config=Config())
     fake_region = "us-fake-1"
 
     initial_client = cache.client(fake_region, "kms")