Added semantic annotation support to view builder

Author: jtc42

examples/builder.py

@@ -7,6 +7,7 @@
 import logging
 
 from labthings.server.quick import create_app
+from labthings.server import semantics
 
 from components.pdf_component import PdfComponent
 
@@ -33,6 +34,7 @@
     "magic_denoise",  # Objects attribute name
     "/denoise",  # URL to bind the property to
     description="A magic denoise property",
+    semtype=semantics.moz.LevelProperty(100, 500, example=200),
 )
 
 labthing.build_property(

src/labthings/server/semantics/base.py

@@ -0,0 +1,18 @@
+from .. import decorators
+from .. import fields
+
+
+class Semantic:
+    pass
+
+
+# BASIC PROPERTIES
+class Property(Semantic):
+    def __init__(self, schema):
+        self.schema = schema
+
+    def __call__(self, viewcls):
+        # Use the class name as the semantic type
+        viewcls = decorators.Semtype(self.__class__.__name__)(viewcls)
+        viewcls = decorators.PropertySchema(self.schema)(viewcls)
+        return viewcls

src/labthings/server/semantics/moz.py

@@ -1,18 +1,7 @@
-from .. import decorators
 from .. import fields
+from .base import Property
 
 # BASIC PROPERTIES
-class Property:
-    def __init__(self, schema):
-        self.schema = schema
-
-    def __call__(self, viewcls):
-        # Use the class name as the semantic type
-        viewcls = decorators.Semtype(self.__class__.__name__)(viewcls)
-        viewcls = decorators.PropertySchema(self.schema)(viewcls)
-        return viewcls
-
-
 class BooleanProperty(Property):
     """https://iot.mozilla.org/schemas/#BooleanProperty"""
 

src/labthings/server/view/builder.py

@@ -11,6 +11,7 @@
     Idempotent,
     Semtype,
 )
+from labthings.server.semantics.base import Semantic
 from . import View, ActionView, PropertyView
 from ..spec.utilities import compile_view_spec
 
@@ -86,8 +87,16 @@ def _update(self, args):
             generated_class
         )
 
+    # Apply semantic type last, to ensure this is always used
     if semtype:
-        generated_class = Semtype(semtype)(generated_class)
+        if isinstance(semtype, str):
+            generated_class = Semtype(semtype)(generated_class)
+        elif isinstance(semtype, Semantic):
+            generated_class = semtype(generated_class)
+        else:
+            logging.error(
+                "Unsupported type for semtype. Must be a string or Semantic object"
+            )
 
     # Compile the generated views spec
     # Useful if its being attached to something other than a LabThing instance
@@ -128,15 +137,23 @@ def _post(self, args):
             generated_class
         )
 
-    if semtype:
-        generated_class = Semtype(semtype)(generated_class)
-
     if safe:
         generated_class = Safe(generated_class)
 
     if idempotent:
         generated_class = Idempotent(generated_class)
 
+    # Apply semantic type last, to ensure this is always used
+    if semtype:
+        if isinstance(semtype, str):
+            generated_class = Semtype(semtype)(generated_class)
+        elif isinstance(semtype, Semantic):
+            generated_class = semtype(generated_class)
+        else:
+            logging.error(
+                "Unsupported type for semtype. Must be a string or Semantic object"
+            )
+
     # Compile the generated views spec
     # Useful if its being attached to something other than a LabThing instance
     compile_view_spec(generated_class)