Read file with JSON content and use them in requests?

I figured out the following to read file using JsonSlurper. I'm able to print each JSON document with the help of 'each' as seen in the code below. I can't figure out how I would pass each of the documents into the request of a test case. I'd really appreciate if anyone could tell me how this can be done!

import groovy.json.*
File f = new File('C:\\contacts.txt')
def slurper = new JsonSlurper()
def jsonText = f.getText()
json = slurper.parseText( jsonText )
json.each{
	log.info it
}