Add schema2 list support

image/docker/schema2/test/test_list.py

@@ -0,0 +1,70 @@
+import json
+import pytest
+
+from image.docker.schema1 import DockerSchema1Manifest
+from image.docker.schema2.manifest import DockerSchema2Manifest
+from image.docker.schema2.list import MalformedSchema2ManifestList, DockerSchema2ManifestList
+from image.docker.schema2.test.test_manifest import MANIFEST_BYTES as v22_bytes
+from image.docker.test.test_schema1 import MANIFEST_BYTES as v21_bytes
+
+@pytest.mark.parametrize('json_data', [
+  '',
+  '{}',
+  """
+  {
+    "unknown": "key"
+  }
+  """,
+])
+def test_malformed_manifest_lists(json_data):
+  with pytest.raises(MalformedSchema2ManifestList):
+    DockerSchema2ManifestList(json_data)
+
+
+MANIFESTLIST_BYTES = json.dumps({
+  "schemaVersion": 2,
+  "mediaType": "application/vnd.docker.distribution.manifest.list.v2+json",
+  "manifests": [
+    {
+      "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+      "size": 983,
+      "digest": "sha256:e6",
+      "platform": {
+        "architecture": "ppc64le",
+        "os": "linux",
+      }
+    },
+    {
+      "mediaType": "application/vnd.docker.distribution.manifest.v1+json",
+      "size": 878,
+      "digest": "sha256:5b",
+      "platform": {
+        "architecture": "amd64",
+        "os": "linux",
+        "features": [
+          "sse4"
+        ]
+      }
+    }
+  ]
+})
+
+def test_valid_manifestlist():
+  def _get_manifest(digest):
+    if digest == 'sha256:e6':
+      return v22_bytes
+    else:
+      return v21_bytes
+
+  manifestlist = DockerSchema2ManifestList(MANIFESTLIST_BYTES)
+  assert len(manifestlist.manifests(_get_manifest)) == 2
+
+  for index, manifest in enumerate(manifestlist.manifests(_get_manifest)):
+    if index == 0:
+      assert isinstance(manifest.manifest_obj, DockerSchema2Manifest)
+      assert manifest.manifest_obj.schema_version == 2
+    else:
+      assert isinstance(manifest.manifest_obj, DockerSchema1Manifest)
+      assert manifest.manifest_obj.schema_version == 1
+
+  assert manifestlist.get_v1_compatible_manifest(_get_manifest).manifest_obj.schema_version == 1