Add user provided SSE-C arguments to CompleteMultipartUpload call

.changes/next-release/bugfix-SSEC-19962.json

@@ -0,0 +1,5 @@
+{
+  "type": "bugfix",
+  "category": "``SSE-C``",
+  "description": "Pass SSECustomer* arguements to CompleteMultipartUpload for upload operations\""
+}

s3transfer/__init__.py

@@ -380,6 +380,12 @@ class MultipartUploader:
         'RequestPayer',
     ]
 
+    COMPLETE_MULTIPART_ARGS = [
+        'SSECustomerKey',
+        'SSECustomerAlgorithm',
+        'RequestPayer',
+    ]
+
     def __init__(
         self,
         client,
@@ -395,11 +401,25 @@ def __init__(
     def _extra_upload_part_args(self, extra_args):
         # Only the args in UPLOAD_PART_ARGS actually need to be passed
         # onto the upload_part calls.
-        upload_parts_args = {}
+        return self._filter_extra_args(
+            extra_args,
+            self.UPLOAD_PART_ARGS,
+        )
+
+    def _extra_complete_multipart_upload_args(self, extra_args):
+        # Only the args in COMPLETE_MULTIPART_ARGS need to be passed
+        # onto the complete_multipart_upload call.
+        return self._filter_extra_args(
+            extra_args,
+            self.COMPLETE_MULTIPART_ARGS,
+        )
+
+    def _filter_extra_args(self, extra_args, allowed_list):
+        filtered_args = {}
         for key, value in extra_args.items():
-            if key in self.UPLOAD_PART_ARGS:
-                upload_parts_args[key] = value
-        return upload_parts_args
+            if key in allowed_list:
+                filtered_args[key] = value
+        return filtered_args
 
     def upload_file(self, filename, bucket, key, callback, extra_args):
         response = self._client.create_multipart_upload(
@@ -424,11 +444,13 @@ def upload_file(self, filename, bucket, key, callback, extra_args):
                     filename, '/'.join([bucket, key]), e
                 )
             )
+        extra_cmu_args = self._extra_complete_multipart_upload_args(extra_args)
         self._client.complete_multipart_upload(
             Bucket=bucket,
             Key=key,
             UploadId=upload_id,
             MultipartUpload={'Parts': parts},
+            **extra_cmu_args,
         )
 
     def _upload_parts(

s3transfer/copies.py

@@ -69,7 +69,12 @@ class CopySubmissionTask(SubmissionTask):
         'TaggingDirective',
     ]
 
-    COMPLETE_MULTIPART_ARGS = ['RequestPayer', 'ExpectedBucketOwner']
+    COMPLETE_MULTIPART_ARGS = [
+        'RequestPayer',
+        'ExpectedBucketOwner',
+        'SSECustomerKey',
+        'SSECustomerAlgorithm',
+    ]
 
     def _submit(
         self, client, config, osutil, request_executor, transfer_future

s3transfer/upload.py

@@ -521,7 +521,12 @@ class UploadSubmissionTask(SubmissionTask):
         'ExpectedBucketOwner',
     ]
 
-    COMPLETE_MULTIPART_ARGS = ['RequestPayer', 'ExpectedBucketOwner']
+    COMPLETE_MULTIPART_ARGS = [
+        'RequestPayer',
+        'ExpectedBucketOwner',
+        'SSECustomerKey',
+        'SSECustomerAlgorithm',
+    ]
 
     def _get_upload_input_manager_cls(self, transfer_future):
         """Retrieves a class for managing input for an upload based on file type

tests/functional/test_copy.py

@@ -629,7 +629,9 @@ def test_copy_passes_args_to_create_multipart_and_upload_part(self):
         self.add_head_object_response(expected_params=head_params)
 
         self._add_params_to_expected_params(
-            add_copy_kwargs, ['create_mpu', 'copy'], self.extra_args
+            add_copy_kwargs,
+            ['create_mpu', 'copy', 'complete_mpu'],
+            self.extra_args,
         )
         self.add_successful_copy_responses(**add_copy_kwargs)
 

tests/unit/test_s3transfer.py

@@ -351,6 +351,8 @@ def test_multipart_upload_injects_proper_kwargs(self):
             Bucket='bucket',
             UploadId='upload_id',
             Key='key',
+            SSECustomerKey='fakekey',
+            SSECustomerAlgorithm='AES256',
         )
 
     def test_multipart_upload_is_aborted_on_error(self):