more complexity in the test cases

apps/app1/button.py

@@ -0,0 +1,29 @@
+import json
+
+from appdaemon.adapi import ADAPI
+
+
+class Button(ADAPI):
+    def initialize(self):
+        name = self.args['button']
+        self.handle = self.listen_event(
+            self.handle_button,
+            'MQTT_MESSAGE',
+            topic=f'zigbee2mqtt/{name}',
+            payload=self.payload_filter,
+        )
+        self.log(f"Started MQTT app in namespace '{self._namespace}'")
+        # raise ValueError
+
+    @staticmethod
+    def payload_filter(payload: str):
+        try:
+            return json.loads(payload)['action'] != ''
+        except Exception:
+            return False
+
+    def handle_button(self, event_name, data, **kwargs):
+        data['payload'] = json.loads(data['payload'])
+        # if data['payload']['action'] != '':
+        json_str = json.dumps(data, indent=4)
+        self.logger.info(f'{event_name} callback with\n{json_str}\n{kwargs}')