Merge branch 'release-0.8.2'

* release-0.8.2:
  Bumping version to 0.8.2
  Scope awscrt.s3 imports to functions (#293)
  Add changelog for subscribers cache (#292)
  Use lru_cache on costly validation function. (#291)

.changes/0.8.2.json

@@ -0,0 +1,7 @@
+[
+  {
+    "category": "Subscribers",
+    "description": "Added caching for Subscribers to improve throughput by up to 24% in high volume transfer",
+    "type": "bugfix"
+  }
+]

CHANGELOG.rst

@@ -2,6 +2,12 @@
 CHANGELOG
 =========
 
+0.8.2
+=====
+
+* bugfix:Subscribers: Added caching for Subscribers to improve throughput by up to 24% in high volume transfer
+
+
 0.8.1
 =====
 

s3transfer/__init__.py

@@ -144,7 +144,7 @@ def __call__(self, bytes_amount):
 from s3transfer.exceptions import RetriesExceededError, S3UploadFailedError
 
 __author__ = 'Amazon Web Services'
-__version__ = '0.8.1'
+__version__ = '0.8.2'
 
 
 class NullHandler(logging.Handler):

s3transfer/crt.py

@@ -15,6 +15,7 @@
 from io import BytesIO
 
 import awscrt.http
+import awscrt.s3
 import botocore.awsrequest
 import botocore.session
 from awscrt.auth import AwsCredentials, AwsCredentialsProvider
@@ -25,13 +26,7 @@
     EventLoopGroup,
     TlsContextOptions,
 )
-from awscrt.s3 import (
-    S3Client,
-    S3RequestTlsMode,
-    S3RequestType,
-    S3ResponseError,
-    get_recommended_throughput_target_gbps,
-)
+from awscrt.s3 import S3Client, S3RequestTlsMode, S3RequestType
 from botocore import UNSIGNED
 from botocore.compat import urlsplit
 from botocore.config import Config
@@ -124,7 +119,6 @@ def create_s3_crt_client(
             use. Specify this argument if you want to use a custom CA cert
             bundle instead of the default one on your system.
     """
-
     event_loop_group = EventLoopGroup(num_threads)
     host_resolver = DefaultHostResolver(event_loop_group)
     bootstrap = ClientBootstrap(event_loop_group, host_resolver)
@@ -159,7 +153,7 @@ def create_s3_crt_client(
 
 def _get_crt_throughput_target_gbps(provided_throughput_target_bytes=None):
     if provided_throughput_target_bytes is None:
-        target_gbps = get_recommended_throughput_target_gbps()
+        target_gbps = awscrt.s3.get_recommended_throughput_target_gbps()
         logger.debug(
             'Recommended CRT throughput target in gbps: %s', target_gbps
         )
@@ -544,7 +538,7 @@ def serialize_http_request(self, transfer_type, future):
         return crt_request
 
     def translate_crt_exception(self, exception):
-        if isinstance(exception, S3ResponseError):
+        if isinstance(exception, awscrt.s3.S3ResponseError):
             return self._translate_crt_s3_response_error(exception)
         else:
             return None

s3transfer/subscribers.py

@@ -10,6 +10,8 @@
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
 # ANY KIND, either express or implied. See the License for the specific
 # language governing permissions and limitations under the License.
+from functools import lru_cache
+
 from s3transfer.compat import accepts_kwargs
 from s3transfer.exceptions import InvalidSubscriberMethodError
 
@@ -28,6 +30,7 @@ def __new__(cls, *args, **kwargs):
         return super().__new__(cls)
 
     @classmethod
+    @lru_cache()
     def _validate_subscriber_methods(cls):
         for subscriber_type in cls.VALID_SUBSCRIBER_TYPES:
             subscriber_method = getattr(cls, 'on_' + subscriber_type)

tests/unit/test_crt.py

@@ -54,7 +54,7 @@ def mock_s3_crt_client():
 @pytest.fixture
 def mock_get_recommended_throughput_target_gbps():
     with mock.patch(
-        's3transfer.crt.get_recommended_throughput_target_gbps'
+        'awscrt.s3.get_recommended_throughput_target_gbps'
     ) as mock_get_target_gbps:
         yield mock_get_target_gbps