ServiceNow Web Service : REST API and Javascript

Creating a RESTful web service in ServiceNow platform by using Javascript

Tools Used in this Tutorial

1. ServiceNow Instance
2. Javascript

Step 1: Creating a Business Rule

This tutorial assumes that you already have an accessible instance of ServiceNow that you can connect to. For more information on getting started with ServiceNow, visit their online tutorial.

Business Rule : MediumRESTAPI

Table      :Incident
When to run: Short Description contains Medium.com
Script
------
var generateOutbound = new MediumRestAPIInterface(); generateOutbound.addRestInfo('post', current.sys_id);

Step 2: Creating a Script Include

In Script Include, we create to separate script include. The first one to communicate with the business rule and the second one to generate JSON.

Script Include : MediumRestAPIInterface

initialize: function() {
  this.baseurl = "Http://medium.com";
  this.jsonConverter = new MediumJSONConverter();
},
addRestInfo: function(method, incidentNumber){
   info = this.jsonConverter.incidentToJSON(incidentNumber);  
   this.endPointREST('MediumREST', info, incidentNumber, method);
 },
endPointREST: function(RESTEndpoint, info, sysId, methodRest){
  var r = new RESTMessage(RESTEndpoint, methodRest);
  r.setStringParameter('baseurl', this.baseurl); 
  r.setStringParameter('incident', sysId);
  r.setXMLParameter('events', info);
  var response = r.execute();
},

Script Include : MediumJSONConverter

incidentToJSON: function(incidentNumber) {
  if (JSUtil.nil(incidentNumber)) return;
  var gr = new GlideRecord("incident");   
  gr.addQuery('number', incidentNumber);
  gr.query();
  if (gr.next()) {    
   return this.incidentGRToJSON(gr);
  }
  return null;
 },
 
   
 incidentGRToJSON: function(pGR) {
  var gr = pGR;  
  var lObj  = new Object(); 
  
  lObj.title = gr.short_description.getDisplayValue();
  lObj.number = gr.number.getDisplayValue();
  lObj.shortDescription = gr.short_description.getDisplayValue();
  return new JSON().encode(lObj);   
 },

Step 3: Creating a REST Message

Navigate to System Web Services>Rest Message