Make xhr request that will be aborted if you call it again. Using mithril request

uniqueReq.js

const merge = require('ramda/src/merge')
const m = require('mithril')

/*

@param {string} key - The unique key of the request
@param {Object} params - The same params used in m.request of mithril
@returns Promise

@link https://mithril.js.org/request.html

Example of use:

function searchUser(email){
  return uniqueReq('searchUser', {
    method: 'GET',
    url: '/users?email=' + email
  })
}

searchUser('[email protected]').then(user => console.log(user))

Every time that you call the function searchUser, the previous request will be aborted.

*/
function uniqueReq(key, params){
	if( ! uniqueReq.xhrs ){ uniqueReq.xhrs = {} }
	if( uniqueReq.xhrs[key] ){ uniqueReq.xhrs[key].abort() }
	return m.request(
		merge(
			params,
			{ config: xhr => uniqueReq.xhrs[key] = xhr }
		)
	)
}