Merge pull request #2483 from thincal/fix/list-objects-with-truncation

s3 list_object: return the NextMarker info if it's truncated

moto/s3/responses.py

@@ -413,7 +413,7 @@ class ResponseObject(_TemplateEnvironmentMixin, ActionAuthenticatorMixin):
         if marker:
             result_keys = self._get_results_from_token(result_keys, marker)
 
-        result_keys, is_truncated, _ = self._truncate_result(result_keys, max_keys)
+        result_keys, is_truncated, next_marker = self._truncate_result(result_keys, max_keys)
 
         template = self.response_template(S3_BUCKET_GET_RESPONSE)
         return 200, {}, template.render(
@@ -423,6 +423,7 @@ class ResponseObject(_TemplateEnvironmentMixin, ActionAuthenticatorMixin):
             result_keys=result_keys,
             result_folders=result_folders,
             is_truncated=is_truncated,
+            next_marker=next_marker,
             max_keys=max_keys
         )
 
@@ -1327,6 +1328,9 @@ S3_BUCKET_GET_RESPONSE = """<?xml version="1.0" encoding="UTF-8"?>
   <MaxKeys>{{ max_keys }}</MaxKeys>
   <Delimiter>{{ delimiter }}</Delimiter>
   <IsTruncated>{{ is_truncated }}</IsTruncated>
+  {% if next_marker %}
+    <NextMarker>{{ next_marker }}</NextMarker>
+  {% endif %}
   {% for key in result_keys %}
     <Contents>
       <Key>{{ key.name }}</Key>

tests/test_s3/test_s3.py

@@ -1247,6 +1247,54 @@ def test_website_redirect_location():
     resp['WebsiteRedirectLocation'].should.equal(url)
 
 
+@mock_s3
+def test_boto3_list_objects_truncated_response():
+    s3 = boto3.client('s3', region_name='us-east-1')
+    s3.create_bucket(Bucket='mybucket')
+    s3.put_object(Bucket='mybucket', Key='one', Body=b'1')
+    s3.put_object(Bucket='mybucket', Key='two', Body=b'22')
+    s3.put_object(Bucket='mybucket', Key='three', Body=b'333')
+
+    # First list
+    resp = s3.list_objects(Bucket='mybucket', MaxKeys=1)
+    listed_object = resp['Contents'][0]
+
+    assert listed_object['Key'] == 'one'
+    assert resp['MaxKeys'] == 1
+    assert resp['IsTruncated'] == True
+    assert resp['Prefix'] == 'None'
+    assert resp['Delimiter'] == 'None'
+    assert 'NextMarker' in resp
+
+    next_marker = resp["NextMarker"]
+
+    # Second list
+    resp = s3.list_objects(
+        Bucket='mybucket', MaxKeys=1, Marker=next_marker)
+    listed_object = resp['Contents'][0]
+
+    assert listed_object['Key'] == 'three'
+    assert resp['MaxKeys'] == 1
+    assert resp['IsTruncated'] == True
+    assert resp['Prefix'] == 'None'
+    assert resp['Delimiter'] == 'None'
+    assert 'NextMarker' in resp
+
+    next_marker = resp["NextMarker"]
+
+    # Third list
+    resp = s3.list_objects(
+        Bucket='mybucket', MaxKeys=1, Marker=next_marker)
+    listed_object = resp['Contents'][0]
+
+    assert listed_object['Key'] == 'two'
+    assert resp['MaxKeys'] == 1
+    assert resp['IsTruncated'] == False
+    assert resp['Prefix'] == 'None'
+    assert resp['Delimiter'] == 'None'
+    assert 'NextMarker' not in resp
+
+
 @mock_s3
 def test_boto3_list_keys_xml_escaped():
     s3 = boto3.client('s3', region_name='us-east-1')