Using key query rather than try catch

Added a unit test for empty content

app/aws/s3.py

@@ -119,12 +119,8 @@ def get_list_of_files_by_suffix(bucket_name, subfolder='', suffix='', last_modif
     )
 
     for page in page_iterator:
-        try:
-            for obj in page['Contents']:
+        for obj in page.get('Contents', []):
             key = obj['Key'].lower()
             if key.endswith(suffix.lower()):
                 if not last_modified or obj['LastModified'] >= last_modified:
                     yield key
-        except KeyError:
-            # Not content for today
-            pass

tests/app/aws/test_s3.py

@@ -208,3 +208,18 @@ def test_get_list_of_files_by_suffix(notify_api, mocker, suffix_str, days_before
     assert sum(1 for x in key) == returned_no
     for k in key:
         assert k == 'bar/foo.ACK.txt'
+
+
+def test_get_list_of_files_by_suffix_empty_contents_return_with_no_error(notify_api, mocker):
+    paginator_mock = mocker.patch('app.aws.s3.client')
+    multiple_pages_s3_object = [
+        {
+            "other_content": [
+                'some_values',
+            ]
+        }
+    ]
+    paginator_mock.return_value.get_paginator.return_value.paginate.return_value = multiple_pages_s3_object
+    key = get_list_of_files_by_suffix('foo-bucket', subfolder='bar', suffix='.pdf')
+
+    assert sum(1 for x in key) == 0

tests/app/celery/test_scheduled_tasks.py

@@ -1058,8 +1058,9 @@ def test_letter_not_raise_alert_if_ack_files_match_zip_list(mocker, notify_db):
     subfoldername = datetime.utcnow().strftime('%Y-%m-%d')
     assert mock_file_list.call_count == 2
     assert mock_file_list.call_args_list == [
-        call(bucket_name='test-letters-pdf', subfolder=subfoldername, suffix='.zip'),
-        call(bucket_name='test.notify.com-ftp', subfolder='root/dispatch', suffix='.ACK.txt', last_modified=yesterday),
+        call(bucket_name=current_app.config['LETTERS_PDF_BUCKET_NAME'], subfolder=subfoldername, suffix='.zip'),
+        call(bucket_name=current_app.config['DVLA_RESPONSE_BUCKET_NAME'], subfolder='root/dispatch',
+             suffix='.ACK.txt', last_modified=yesterday),
     ]
     assert mock_get_file.call_count == 1