Use the string builder processor to add a new attribute (without spaces or special characters) to an event with the result of the provided template. This enables aggregation of different attributes or raw strings into a single attribute.

The template is defined by both raw text and blocks with the syntax %{attribute_path}.


  • This processor only accepts attributes with values or an array of values in the block (see examples in the UI section below.
  • If an attribute cannot be used (object or array of object), it is replaced by an empty string or the entire operation is skipped depending on your selection.
  • If a target attribute already exists, it is overwritten by the result of the template.
  • Results of a template cannot exceed 256 characters.

Example String Builder

String builder processor