Eliminate built action schemas

build_action_schema was returning empty schemas.  I'm now just
directly composing input, output, and Action schemas
with allOf which works nicely.

This may need to be fixed for the thing description, though.

src/labthings/apispec/plugins.py

@@ -158,16 +158,16 @@ def spec_for_action(self, action):
             # I think the code below does it - but I'm not yet convinced it is working
             #TODO: add tests to validate this
             plugin = get_marshamallow_plugin(self.spec)
-            action_io_schema = build_action_schema(
-                action_output, 
-                action_input, 
-                base_class=Schema, 
-                name=f"{action.__name__}InputOutputSchema"
-            )
             action_schema = {
                 "allOf": [
                     plugin.resolver.resolve_schema_dict(ActionSchema),
-                    plugin.resolver.resolve_schema_dict(action_io_schema),
+                    {
+                        "type": "object",
+                        "parameters": {
+                            "input": plugin.resolver.resolve_schema_dict(action_input),
+                            "output": plugin.resolver.resolve_schema_dict(action_output),
+                        }
+                    }
                 ]
             }
             # The line below builds an ActionSchema subclass.  This works and

src/labthings/schema.py

@@ -161,6 +161,7 @@ def build_action_schema(
     :param name: str:  (Default value = None)
 
     """
+    #FIXME: this seems to lose the schemas.  I suspect this is down to `nest_if_needed`.
     # Create a name for the generated schema
     if not name:
         name = str(id(output_schema))

tests/test_schema.py

@@ -64,3 +64,11 @@ def test_build_action_schema_typeerror():
     output_schema = object()
     with pytest.raises(TypeError):
         action_schema = schema.build_action_schema(input_schema, output_schema)
+
+def test_nest_if_needed():
+    nested_schema = schema.nest_if_needed(schema.ActionSchema())
+    assert isinstance(nested_schema, fields.Field)
+    nested_dict = schema.nest_if_needed({"name": fields.Integer()})
+    assert isinstance(nested_schema, fields.Field)
+    nested_field = schema.nest_if_needed(fields.Boolean())
+    assert isinstance(nested_schema, fields.Field)