This promise type assures that an attribute, with the given name and value, will be present in the specified node within the XML file. If the attribute is not found, the default promise is to insert the attribute, into the specified node. If the attribute is already present, the default promise is to insure that the attribute value is set to the given value. The specified node and attribute value are each determined by body-attributes. The promise object referred to is a literal string representation of the name of the attribute to be set.
bundle edit_xml example
attribute_value => "cfe_host",
select_xpath => "/Server/Service/Engine/Host";
Note that typically only a single attribute, within a single selected
node, is set in each
set_attribute promise. You may of course have
multiple promises that each set an attribute.
Description: Value of the attribute to be inserted into the XPath node of the XML file
Allowed input range: (arbitrary string)