Test Class for Xml Dom Document & WebServices

Question

My Apex class

public with sharing class helpTextClass {
  public string main(string url)
    {

            Http h = new Http();    
            HttpRequest req = new HttpRequest();
            req.setEndpoint(url);
            req.setMethod('GET');
            req.setTimeout(60000);
            string hresult='';
             if(isValid==true)
            {
                HttpResponse hres = h.send(req);
                hresult = hres.getBody();
                //system.debug('------'+hresult);
            }else{
                hresult = '<?xml version="1.0" encoding="ISO-8859-1"?><HelpTextDetails><BaseURL>http://click-pledge.v-empower.com/web/HelpText/HelpTextXml</BaseURL><HelpTab TabName="C&P InvoicePayment" label="C&P InvoicePayment"><TabSection Name="C&P InvoicePayment"></TabSection></HelpTab></HelpTextDetails>';

            }           
            return hresult;
         }
       public class subTabnames{
        public string description{get;set;}
        public string link{get;set;}
        public string video{get;set;}
    }   
public  map<string,map<string,subTabnames>> helpText(){
     finalMap = new map<string,map<string,subTabnames>>();
      url = 'http://click-pledge.v-empower.com/web/HelpText/HelpTextXml/HelpTextXml.xml';
        isValid=true;           
        try{    
            helpXml = main(url);
        }catch(System.CalloutException e){
            system.debug('Error: '+e);
        }


     Dom.document doc = new Dom.document();
       doc.load(helpxml);
       Dom.XMLNode elementsList = doc.getRootElement();
        if(elementsList !=NULL){
             for(Dom.XMLNode child : elementsList.getChildElements()) { 
                 boolean checkcategory = false;
                 // Some code here
              }
       }       
      return finalmap;

}   

My Test Class for this is

@istest
public class test_helpTextPage{
    public static testmethod void helptest(){
        helptextclass hc = new helpTextClass();      
         helpTextclass.subTabNames tabNames = new helpTextclass.subTabnames();        
        hc.main('http://click-pledge.v-empower.com/web/HelpText/HelpTextXml/HelpTextXml.xml');
        hc.isValid = true;      
         hc.helpText();  
    }
}

the code coverage for this is 53% and it is not covering this Part

 Dom.document doc = new Dom.document();
       doc.load(helpxml);
       Dom.XMLNode elementsList = doc.getRootElement();
        if(elementsList !=NULL){
             for(Dom.XMLNode child : elementsList.getChildElements()) { 
                 boolean checkcategory = false;
                 // Some code here
              }
       }       
      return finalmap;

What should I do to cover this also.Help Pls!!!!!!

Answer 1

http://www.salesforce.com/us/developer/docs/apexcode/Content/apex_classes_restful_http_testing_httpcalloutmock.htm

You have to implement mock callouts for this .In test class the actual call wont be made and hence mock interface you can use to achieve code coverage.

refer this thread :Testing WebServiceCallout with HttpCalloutMock

caution:Testing HttpCallout with HttpCalloutMock and UnitTest Created Data

There is known issue of Pending DML statements

Refer the blog:

http://blogs.developerforce.com/developer-relations/2012/10/testing-http-callouts-with-static-data-in-winter-13.html#comment-688228232