Fix wrongly mandatory fields for modulemd_defaults

CHANGELOG.md

@@ -12,6 +12,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - client.search_content method
 - Introduced 'population_sources' and 'ubi_population' attributes for yum repository
 
+### Fixed
+- 'stream' and 'profiles' are now optional on modulemd_defaults units, rather
+  than incorrectly mandatory (leading to schema validation errors)
+
 ## [2.5.0] - 2020-02-25
 
 ### Added

pubtools/pulplib/_impl/model/unit/modulemd_defaults.py

@@ -16,17 +16,14 @@ class ModulemdDefaultsUnit(Unit):
     name = pulp_attrib(type=str, pulp_field="name")
     """The name of this modulemd defaults unit"""
 
-    stream = pulp_attrib(type=str, pulp_field="stream")
-    """The stream of this modulemd defaults unit"""
-
     repo_id = pulp_attrib(type=str, pulp_field="repo_id")
     """The repository ID bound to this modulemd defaults unit"""
 
-    profiles = pulp_attrib(pulp_field="profiles")
-    """The profiles of this modulemd defaults unit.
+    stream = pulp_attrib(type=str, pulp_field="stream", default=None)
+    """The stream of this modulemd defaults unit"""
 
-    The type for this attribute is omitted to allow for either dict or None.
-    """
+    profiles = pulp_attrib(type=dict, pulp_field="profiles", default=None)
+    """The profiles of this modulemd defaults unit."""
 
     repository_memberships = pulp_attrib(
         default=None,

pubtools/pulplib/_impl/schema/unit.yaml

@@ -165,7 +165,6 @@ definitions:
     required:
     - _content_type_id
     - name
-    - stream
     - repo_id
 
   # Schema for any unknown type of unit

tests/repository/test_search_content.py

@@ -198,7 +198,6 @@ def test_modulemd_defaults_content(client, requests_mocker):
                 "metadata": {
                     "_content_type_id": "modulemd_defaults",
                     "name": "mdd",
-                    "stream": "1.0",
                     "repo_id": "some-repo",
                     "profiles": {"p1": ["something"]},
                 }