add %fieldname

contrib/etc/ebusd/mqtt-hassio.cfg

@@ -48,8 +48,10 @@
 #     Available as "%type_map".
 
 # 6. other field specific variables for each field (only once for each message if the topic is field specific):
-#   %index the field index (excluding ignored fields).
-#   %field the field name (or the field index if no name is defined or the names are not unique in the message).
+#   %index the numeric field index (excluding ignored fields).
+#   %field the field name and key for JSON objects (equals the field index if no name is defined or the names are not
+#     unique in the message).
+#   %fieldname the field name (and nothing else like in %field, might be empty though!)
 #   %type the field type (one of "number", "list", "string", "date", "time", or "datetime").
 #   %basetype the base data type ID (e.g. "UCH").
 #   %comment the field comment (if any).

contrib/etc/ebusd/mqtt-integration.cfg

@@ -42,8 +42,10 @@
 #     Available as "%type_map".
 
 # 6. other field specific variables for each field (only once for each message if the topic is field specific):
-#   %index the field index (excluding ignored fields).
-#   %field the field name (or the field index if no name is defined or the names are not unique in the message).
+#   %index the numeric field index (excluding ignored fields).
+#   %field the field name and key for JSON objects (equals the field index if no name is defined or the names are not
+#     unique in the message).
+#   %fieldname the field name (and nothing else like in %field, might be empty though!)
 #   %type the field type (one of "number", "list", "string", "date", "time", or "datetime").
 #   %basetype the base data type ID (e.g. "UCH").
 #   %comment the field comment (if any).

src/ebusd/mqtthandler.cpp

@@ -1439,6 +1439,7 @@ void MqttHandler::run() {
             MqttReplacers values = msgValues;  // need a copy here as the contents are manipulated
             values.set("index", static_cast<signed>(index));
             values.set("field", fieldName);
+            values.set("fieldname", field->getName(-1));
             values.set("type", typeStr);
             values.set("type_map", str);
             values.set("basetype", dataType->getId());