feat: convert client suppliers to callables

Author: mattsb42-aws

src/aws_encryption_sdk/keyrings/aws_kms/__init__.py

@@ -300,7 +300,7 @@ def _do_aws_kms_decrypt(client_supplier, key_name, encrypted_data_key, encryptio
 
     """
     region = _region_from_key_id(encrypted_data_key.key_provider.key_info.decode("utf-8"))
-    client = client_supplier.client(region)
+    client = client_supplier(region)
     response = client.decrypt(
         CiphertextBlob=encrypted_data_key.encrypted_data_key,
         EncryptionContext=encryption_context,
@@ -324,7 +324,7 @@ def _do_aws_kms_encrypt(client_supplier, key_name, plaintext_data_key, encryptio
     Any errors encountered are passed up the chain without comment.
     """
     region = _region_from_key_id(key_name)
-    client = client_supplier.client(region)
+    client = client_supplier(region)
     response = client.encrypt(
         KeyId=key_name,
         Plaintext=plaintext_data_key.data_key,
@@ -347,7 +347,7 @@ def _do_aws_kms_generate_data_key(client_supplier, key_name, encryption_context,
 
     """
     region = _region_from_key_id(key_name)
-    client = client_supplier.client(region)
+    client = client_supplier(region)
     response = client.generate_data_key(
         KeyId=key_name,
         NumberOfBytes=algorithm.kdf_input_len,

src/aws_encryption_sdk/keyrings/aws_kms/client_suppliers.py

@@ -35,13 +35,13 @@ class ClientSupplier(object):
 
     """
 
-    def client(self, region_name):
+    def __call__(self, region_name):
         # type: (Union[None, str]) -> BaseClient
         """Return a client for the requested region.
 
         :rtype: BaseClient
         """
-        raise NotImplementedError("'ClientSupplier' does not implement 'client'")
+        raise NotImplementedError("'ClientSupplier' is not callable")
 
 
 @attr.s
@@ -61,7 +61,7 @@ def __attrs_post_init__(self):
         """Set up internal client cache."""
         self._cache = ClientCache(botocore_session=self._botocore_session)
 
-    def client(self, region_name):
+    def __call__(self, region_name):
         # type: (Union[None, str]) -> BaseClient
         """Return a client for the requested region.
 
@@ -100,7 +100,7 @@ def client(self, region_name):
         if region_name not in self.allowed_regions:
             raise UnknownRegionError("Unable to provide client for region '{}'".format(region_name))
 
-        return self._supplier.client(region_name)
+        return self._supplier(region_name)
 
 
 @attr.s
@@ -123,7 +123,7 @@ def __attrs_post_init__(self):
         """Set up internal client supplier."""
         self._supplier = DefaultClientSupplier(botocore_session=self._botocore_session)
 
-    def client(self, region_name):
+    def __call__(self, region_name):
         # type: (Union[None, str]) -> BaseClient
         """Return a client for the requested region.
 
@@ -133,4 +133,4 @@ def client(self, region_name):
         if region_name in self.denied_regions:
             raise UnknownRegionError("Unable to provide client for region '{}'".format(region_name))
 
-        return self._supplier.client(region_name)
+        return self._supplier(region_name)

test/functional/keyrings/aws_kms/test_client_suppliers.py

@@ -19,7 +19,7 @@ def test_default_supplier_not_implemented():
     test = ClientSupplier()
 
     with pytest.raises(NotImplementedError) as excinfo:
-        test.client("region")
+        test("region")
 
     excinfo.match("'ClientSupplier' does not implement 'client'")
 
@@ -30,7 +30,7 @@ def test_default_supplier_uses_cache():
     region = "us-west-2"
     expected = supplier._cache.client(region_name=region, service="kms")
 
-    test = supplier.client(region)
+    test = supplier(region)
 
     assert test is expected
 
@@ -66,14 +66,14 @@ def test_allow_regions_supplier_invalid_parameters(kwargs):
 def test_allow_regions_supplier_allows_allowed_region():
     test = AllowRegionsClientSupplier(allowed_regions=["us-west-2", "us-east-2"])
 
-    assert test.client("us-west-2")
+    assert test("us-west-2")
 
 
 def test_allow_regions_supplier_denied_not_allowed_region():
     test = AllowRegionsClientSupplier(allowed_regions=["us-west-2", "us-east-2"])
 
     with pytest.raises(UnknownRegionError) as excinfo:
-        test.client("ap-northeast-2")
+        test("ap-northeast-2")
 
     excinfo.match("Unable to provide client for region 'ap-northeast-2'")
 
@@ -102,12 +102,12 @@ def test_deny_regions_supplier_denies_denied_region():
     test = DenyRegionsClientSupplier(denied_regions=["us-west-2", "us-east-2"])
 
     with pytest.raises(UnknownRegionError) as excinfo:
-        test.client("us-west-2")
+        test("us-west-2")
 
     excinfo.match("Unable to provide client for region 'us-west-2'")
 
 
 def test_deny_regions_supplier_allows_not_denied_region():
     test = DenyRegionsClientSupplier(denied_regions=["us-west-2", "us-east-2"])
 
-    assert test.client("ap-northeast-2")
+    assert test("ap-northeast-2")