Description: Returns a URL-friendly version of the Subject. This is useful, for instance, when using an attribute value to indicate the URL of a website.

Subject Type: String

Arguments: No arguments

Return Type: String

Examples: We can URL-Encode an attribute named "url" by using the Expression ${url:urlEncode()}. If the value of the "url" attribute is "https://nifi.apache.org/some value with spaces", this Expression will then return "https://nifi.apache.org/some%20value%20with%20spaces".