unable to pass Optional action header field variables in upload action

could you please help.how do pass Optional action header field variables in upload action

Optional action header field variables
Along with the standard action header content, the following optional fields can be included. Each must be appended to the end of the header, prefaced by an ampersand (“&”).

index-zip=2:
md5=[hash]..etc

ns.upload(local_source, netstorage_destination, (error, response, body) => {
if (error) { // errors other than http response codes
console.log(Got error: ${error.message})
}
if (response.statusCode == 200) {
console.log(body)
}
});

Start by tracing the ns.upload entry point and how it assembles the NetStorage action header; the payload does not name implementation files or tests. Clarify the intended API for supplying optional fields such as index-zip and md5, then verify that the resulting header is sent correctly and add or update coverage for the chosen behavior.