feat(#495): add validation against existing device names

bec_widgets/widgets/services/device_browser/device_item/device_config_dialog.py

@@ -5,6 +5,7 @@ from bec_lib.atlas_models import Device as DeviceConfigModel
 from bec_lib.config_helper import CONF as DEVICE_CONF_KEYS
 from bec_lib.config_helper import ConfigHelper
 from bec_lib.logger import bec_logger
+from pydantic import ValidationError, field_validator
 from qtpy.QtCore import QSize, Qt, QThreadPool, Signal
 from qtpy.QtWidgets import (
     QApplication,
@@ -77,6 +78,7 @@ class DeviceConfigDialog(BECWidget, QDialog):
         if self._action == "update":
             self._form._validity.setVisible(False)
         else:
+            self._set_schema_to_check_devices()
             self._form._validity.setVisible(True)
             self._form.validity_proc.connect(self.enable_buttons_for_validity)
         self._add_overlay()
@@ -86,6 +88,17 @@ class DeviceConfigDialog(BECWidget, QDialog):
         self._form.validate_form()
         self._overlay_widget.setVisible(False)
 
+    def _set_schema_to_check_devices(self):
+        class _NameValidatedConfigModel(DeviceConfigModel):
+            @field_validator("name")
+            @staticmethod
+            def _validate_name(value: str, *_):
+                if value in self.dev:
+                    raise ValueError(f"A device with name {value} already exists!")
+                return value
+
+        self._form.set_schema(_NameValidatedConfigModel)
+
     def _add_form(self):
         self._form_widget = QWidget()
         self._form_widget.setLayout(self._layout)

bec_widgets/widgets/services/device_browser/device_item/device_config_form.py

@@ -55,7 +55,9 @@ class DeviceConfigForm(PydanticModelForm):
             qapp.theme_signal.theme_updated.connect(self.set_pretty_display_theme)  # type: ignore
 
     def set_schema(self, schema: type[BaseModel]):
-        raise TypeError("This class doesn't support changing the schema")
+        if not issubclass(schema, DeviceConfigModel):
+            raise TypeError("This class doesn't support changing the schema")
+        super().set_schema(schema)
 
     def set_data(self, data: DeviceConfigModel):  # type: ignore # This class locks the type
         super().set_data(data)