Add Custom Action using JSOM

AddCustomAction.js

var context = SP.ClientContext.get_current()
var web = context.get_web()
var actions = web.get_userCustomActions();
context.load(web)
context.load(actions)
context.executeQueryAsync(
  function () {
	  	var newAction = actions.add();

		newAction.set_description('abc123')  
		newAction.set_location('ScriptLink') 
		var scriptBlock = 'var headID = document.getElementsByTagName("head")[0];var newScript = document.createElement("script");newScript.type = "text/javascript";newScript.src = "' 
		scriptBlock += web.get_url() + '/scripts/scriptfile.js?ver=' + ((new Date()) * 1); 
		scriptBlock += '";headID.appendChild(newScript);'; 
		newAction.set_scriptBlock(scriptBlock)
		newAction.update() 
		context.executeQueryAsync(
			function () {
			  	console.log("Success")
			},
			function () {
				console.log('Error')
		})
 
},
function () {
  console.log('Error')
})