Add include_none_values ClassVar to JSONObject; apply to response-only classes (#466)

* Add include_none_values ClassVar to JSONObject; apply to response-only structures

* Add unit test case

Author: lgarber-akamai

linode_api4/objects/image.py

@@ -24,6 +24,8 @@ class ImageRegion(JSONObject):
     The region and status of an image replica.
     """
 
+    include_none_values = True
+
     region: str = ""
     status: Optional[ReplicationStatus] = None
 

linode_api4/objects/lke.py

@@ -55,6 +55,8 @@ class LKENodePoolTaint(JSONObject):
     applied to a node pool.
     """
 
+    include_none_values = True
+
     key: Optional[str] = None
     value: Optional[str] = None
     effect: Optional[str] = None
@@ -103,6 +105,8 @@ class LKEClusterControlPlaneACLAddresses(JSONObject):
     to access an LKE cluster's control plane.
     """
 
+    include_none_values = True
+
     ipv4: Optional[List[str]] = None
     ipv6: Optional[List[str]] = None
 
@@ -116,6 +120,8 @@ class LKEClusterControlPlaneACL(JSONObject):
     NOTE: Control Plane ACLs may not currently be available to all users.
     """
 
+    include_none_values = True
+
     enabled: bool = False
     addresses: Optional[LKEClusterControlPlaneACLAddresses] = None
 

linode_api4/objects/serializable.py

@@ -58,6 +58,12 @@ class JSONObject(metaclass=JSONFilterableMetaclass):
         )
     """
 
+    include_none_values: ClassVar[bool] = False
+    """
+    If true, all None values for this class will be explicitly included in 
+    the serialized output for instance of this class.
+    """
+
     always_include: ClassVar[Set[str]] = {}
     """
     A set of keys corresponding to fields that should always be
@@ -169,7 +175,7 @@ def should_include(key: str, value: Any) -> bool:
             Returns whether the given key/value pair should be included in the resulting dict.
             """
 
-            if key in cls.always_include:
+            if cls.include_none_values or key in cls.always_include:
                 return True
 
             hint = type_hints.get(key)

test/unit/objects/serializable_test.py

@@ -26,3 +26,24 @@ class Foo(JSONObject):
         assert foo["foo"] == "test"
         assert foo["bar"] == "test2"
         assert foo["baz"] == "test3"
+
+    def test_serialize_optional_include_None(self):
+        @dataclass
+        class Foo(JSONObject):
+            include_none_values = True
+
+            foo: Optional[str] = None
+            bar: Optional[str] = None
+            baz: str = None
+
+        foo = Foo().dict
+
+        assert foo["foo"] is None
+        assert foo["bar"] is None
+        assert foo["baz"] is None
+
+        foo = Foo(foo="test", bar="test2", baz="test3").dict
+
+        assert foo["foo"] == "test"
+        assert foo["bar"] == "test2"
+        assert foo["baz"] == "test3"