Merge pull request #3172 from DataDog/haissam/fix-image_tag_extractor

[docker] fix image tag extraction

Author: hkaj

tests/checks/integration/test_docker_daemon.py

@@ -614,10 +614,16 @@ def test_image_tags_extraction(self):
             ({'RepoTags': ['localhost/redis:latest']}, [['localhost/redis'], ['latest']]),
             ({'RepoTags': ['localhost:5000/redis:latest']}, [['localhost:5000/redis'], ['latest']]),
             ({'RepoTags': ['localhost:5000/redis:latest', 'localhost:5000/redis:v1.1']}, [['localhost:5000/redis'], ['latest', 'v1.1']]),
+            ({'RepoTags': [], 'RepoDigests': [u'datadog/docker-dd-agent@sha256:47a59c2ea4f6d9555884aacc608b303f18bde113b1a3a6743844bfc364d73b44']},
+                [['datadog/docker-dd-agent'], None]),
         ]
         for entity in entities:
             self.assertEqual(sorted(DockerUtil.image_tag_extractor(entity[0], 0)), sorted(entity[1][0]))
-            self.assertEqual(sorted(DockerUtil.image_tag_extractor(entity[0], 1)), sorted(entity[1][1]))
+            tags = DockerUtil.image_tag_extractor(entity[0], 1)
+            if isinstance(entity[1][1], list):
+                self.assertEqual(sorted(tags), sorted(entity[1][1]))
+            else:
+                self.assertEqual(tags, entity[1][1])
 
     def test_container_name_extraction(self):
         containers = [

utils/dockerutil.py

@@ -382,7 +382,7 @@ def image_tag_extractor(cls, entity, key):
                 # the split will be like [repo_url, repo_port/image_name, image_tag]. Let's avoid that
                 split = [':'.join(split[:-1]), split[-1]]
             return [split[key]]
-        if "RepoTags" in entity:
+        if entity.get('RepoTags'):
             splits = [el.split(":") for el in entity["RepoTags"]]
             tags = set()
             for split in splits:
@@ -392,6 +392,14 @@ def image_tag_extractor(cls, entity, key):
                     tags.add(split[key])
             if len(tags) > 0:
                 return list(tags)
+        elif entity.get('RepoDigests'):
+            # the human-readable tag is not mentioned in RepoDigests, only the image name
+            if key != 0:
+                return None
+            split = entity['RepoDigests'][0].split('@')
+            if len(split) > 1:
+                return [split[key]]
+
         return None
 
     @classmethod