Validate fields used in custom form config

src/servala/core/forms.py

@@ -178,8 +178,80 @@ class ServiceDefinitionAdminForm(forms.ModelForm):
                     {"form_config": _("Schema error: {}").format(e.message)}
                 )
 
+            self._validate_field_mappings(form_config, cleaned_data)
+
         return cleaned_data
 
+    def _validate_field_mappings(self, form_config, cleaned_data):
+        if not self.instance.pk:
+            return
+        crd = self.instance.offering_control_planes.all().first()
+        if not crd:
+            return
+
+        schema = None
+        try:
+            schema = crd.resource_schema
+        except Exception as e:
+            pass
+
+        if not schema or not (spec_schema := schema.get("properties", {}).get("spec")):
+            return
+
+        valid_paths = self._extract_field_paths(spec_schema, "spec") | {"name"}
+        included_mappings = set()
+        errors = []
+        for fieldset in form_config.get("fieldsets", []):
+            for field in fieldset.get("fields", []):
+                mapping = field.get("controlplane_field_mapping")
+                included_mappings.add(mapping)
+                if mapping and mapping not in valid_paths:
+                    field_name = field.get("name", mapping)
+                    errors.append(
+                        _(
+                            "Field '{}' has invalid mapping '{}'. Valid paths are: {}"
+                        ).format(
+                            field_name,
+                            mapping,
+                            ", ".join(sorted(valid_paths)[:10])
+                            + ("..." if len(valid_paths) > 10 else ""),
+                        )
+                    )
+
+        if "name" not in included_mappings:
+            raise forms.ValidationError(
+                {
+                    "form_config": _(
+                        "You must include a `name` field in the custom form config."
+                    )
+                }
+            )
+
+        if errors:
+            raise forms.ValidationError({"form_config": errors})
+
+    def _extract_field_paths(self, schema, prefix=""):
+        paths = set()
+
+        if not isinstance(schema, dict):
+            return paths
+
+        if "type" in schema and schema["type"] != "object":
+            if prefix:
+                paths.add(prefix)
+
+        if schema.get("properties"):
+            for prop_name, prop_schema in schema["properties"].items():
+                new_prefix = f"{prefix}.{prop_name}" if prefix else prop_name
+                paths.add(new_prefix)
+                paths.update(self._extract_field_paths(prop_schema, new_prefix))
+
+        if schema.get("type") == "array" and "items" in schema:
+            if prefix:
+                paths.add(prefix)
+
+        return paths
+
     def save(self, *args, **kwargs):
         self.instance.api_definition = self.cleaned_data["api_definition"]
         return super().save(*args, **kwargs)