Apex Testing and Best practices presented in Boston Salesforce world tour

1. Introduction to Apex Testing
Salesforce World Tour Boston

2. Jitendra Zaa
Force.com MVP
@JitendraZaa
http://JitendraZaa.com

4. • Why do we need unit test
• Getting started with Apex test classes
• Testing Visualforce Controller
• Web services Testing
• Testing Apex Callouts
• Best Practices
• Q&A
Agenda

5. • Development of robust, error-free code
• As Salesforce is multitenant platform, make sure none of governor limits are hitting
• To deploy code on production, unit tests are required
• Minimum 75% of test coverage is required
• Code coverage = number of unique apex lines executed / total number of lines in trigger , classes
• These excludes comments, test methods
• Unit tests are critical part of Salesforce development as it ensures success
• Provides automated regression testing framework to make sure bug free future development
Why unit test

6. • Apex code that tests other Apex code
• Annotate class with @isTest
• Class methods (static)
• Defined with testMethod keyword
• Classes defined with @isTest annotation does not count against organization limit of 2MB of Apex
code.
How to write unit test

7. @isTest
public class myClass {
static testMethod void myTest() {
// Add test method logic using System.assert(), System.assertEquals()
// and System.assertNotEquals() here.
}
}
Sample Code

8. • Used to test governor limits
• To make sure all Asynchronous code executes when stoptest() method is called
• When startTest() method is called, fresh governor limits are applied until stopTest() is
executed
• startTest() and stopTest() can be called only once in testMethod.
Test.startTest() and Test.stopTest()

9. trigger OverwriteTestAccountDescriptions on Account (before insert) {
for(Account a: Trigger.new){
if (a.Name.toLowerCase().contains('test')){
a.Description =
'This Account is probably left over from testing. It should probably
be deleted.';
}
}
}
Trigger to be tested
Sample Code

10. static testMethod void verifyAccountDescriptionsWhereOverwritten(){
// Perform our data preparation.
List<Account> accounts = new List<Account>{};
for(Integer i = 0; i < 200; i++){
Account a = new Account(Name = 'Test Account ' + i);
accounts.add(a);
}
// Start the test, this changes governor limit context to
// that of trigger rather than test.
test.startTest();
Test method to test Trigger
Sample Code

11. // Insert the Account records that cause the trigger to execute.
insert accounts;
// Stop the test, this changes limit context back to test from trigger.
test.stopTest();
// Query the database for the newly inserted records.
List<Account> insertedAccounts = [SELECT Name, Description
FROM Account
WHERE Id IN&nbsp;:accounts];
// Assert that the Description fields contains the proper value now.
for(Account a&nbsp;: insertedAccounts){
System.assertEquals(
'This Account is probably left over from testing. It should probably
be deleted.',
a.Description);
}
}
Sample Code (cont.)

12. • By default Apex code runs in system mode
• Permission and record sharing are not taken into consideration
• System.runAs() method helps to change test context to either existing or new user
• System.runAs() can only be used in testMethods
System.runAs()

13. public class TestRunAs {
public static testMethod void testRunAs() {
// This code runs as the system user
Profile p = [select id from profile where name='Standard User'];
User u = new User(alias = 'standt',
email='standarduser@testorg.com',
emailencodingkey='UTF-8', lastname='Testing',
languagelocalekey='en_US', localesidkey='en_US', profileid = p.Id,
timezonesidkey='America/Los_Angeles',
username='standarduser@testorg.com');
System.runAs(u) {
// The following code runs as user 'u'
System.debug('Current User: ' + UserInfo.getUserName());
System.debug('Current Profile: ' + UserInfo.getProfileId()); }
// Run some code that checks record sharing
}
}
Sample Code

14. • Use TestVisible annotation to allow Test methods to access private or protected members of another
class
• These members can be methods , member variables or inner classes
@TestVisible

15. public class TestVisibleExample {
// Private member variable
@TestVisible private static Integer recordNumber = 1;
// Private method
@TestVisible private static void updateRecord(String name) {
// Do something
}
}
Actual code to Test
Sample Code

16. @isTest
private class TestVisibleExampleTest {
@isTest static void test1() {
// Access private variable annotated with TestVisible
Integer i = TestVisibleExample.recordNumber;
System.assertEquals(1, i);
// Access private method annotated with TestVisible
TestVisibleExample.updateRecord('RecordName');
// Perform some verification
}
}
Test Method
Sample Code

17. • Like all Apex classes and Triggers, Visualforce controllers also requires Test methods
• Test methods can automate user interaction by setting query parameter or navigating to different pages
Test Visualforce Controller

18. public static testMethod void testMyController() {
//Use the PageReference Apex class to instantiate a page
PageReference pageRef = Page.success;
//In this case, the Visualforce page named 'success' is the starting
point of this test method.
Test.setCurrentPage(pageRef);
//Instantiate and construct the controller class.
Thecontroller controller = new Thecontroller();
//Example of calling an Action method. Same as calling any other Apex
method.
String nextPage = controller.save().getUrl();
//Check that the save() method returns the proper URL.
System.assertEquals('/apex/failure?error=noParam', nextPage);
}
Sample Code

19. • Generated code from WSDL is saved as Apex class and therefore needs to be tested
• By default test methods does not support Web service call outs
• Apex provides the built-in WebServiceMock interface and the Test.setMock method that you can
use to receive fake responses in a test method.
• Instruct the Apex runtime to generate a fake response whenever WebServiceCallout.invoke is
called.
Testing Web Services

20. @isTest
global class WebServiceMockImpl implements WebServiceMock {
global void doInvoke(
Object stub,
Object request,
Map<String, Object> response,
String endpoint,
String soapAction,
String requestName,
String responseNS,
String responseName,
String responseType) {
docSample.EchoStringResponse_element respElement =
new docSample.EchoStringResponse_element();
respElement.EchoStringResult = 'Mock response';
response.put('response_x', respElement);
}
}
Sample Code

21. public class WebSvcCallout {
public static String callEchoString(String input) {
docSample.DocSamplePort sample = new docSample.DocSamplePort();
sample.endpoint_x = 'http://api.salesforce.com/foo/bar';
// This invokes the EchoString method in the generated class
String echo = sample.EchoString(input);
return echo;
}
}
Actual code that calls Web service
Sample Code

22. @isTest
private class WebSvcCalloutTest {
@isTest static void testEchoString() {
// This causes a fake response to be generated
Test.setMock(WebServiceMock.class, new WebServiceMockImpl());
// Call the method that invokes a callout
String output = WebSvcCallout.callEchoString('Hello World!');
// Verify that a fake result is returned
System.assertEquals('Mock response', output);
}
}
Test class to test Web service response
Sample Code

23. • Apex has ability to call external Web services like Amazon, Facebook or any other Web service.
• Salesforce does not has any control over response of external Web services.
• Apex callouts can be tested either using HttpCalloutMock interface or using Static Resources.
• HttpCalloutMock Is used to generate fake HttpResponse for testing purpose.
Testing Apex Callouts

24. @isTest
global class MockHttpResponseGenerator implements HttpCalloutMock {
// Implement this interface method
global HTTPResponse respond(HTTPRequest req) {
// Create a fake response
HttpResponse res = new HttpResponse();
res.setHeader('Content-Type', 'application/json');
res.setBody('{"foo":"bar"}');
res.setStatusCode(200);
return res;
}
}
Implementing HttpCalloutMock interface
Sample Code

25. public class CalloutClass {
public static HttpResponse getInfoFromExternalService() {
HttpRequest req = new HttpRequest();
req.setEndpoint('http://api.salesforce.com/foo/bar');
req.setMethod('GET');
Http h = new Http();
HttpResponse res = h.send(req);
return res;
}
}
Actual code to be tested
Sample Code

26. @isTest
private class CalloutClassTest {
@isTest static void testCallout() {
// Set mock callout class
Test.setMock(HttpCalloutMock.class, new MockHttpResponseGenerator());
// This causes a fake response to be sent
// from the class that implements HttpCalloutMock.
HttpResponse res = CalloutClass.getInfoFromExternalService();
// Verify response received contains fake values
String contentType = res.getHeader('Content-Type');
System.assert(contentType == 'application/json');
String actualValue = res.getBody();
String expectedValue = '{"foo":"bar"}';
System.assertEquals(actualValue, expectedValue);
System.assertEquals(200, res.getStatusCode());
}
}
Complete Test methods
Sample Code

27. • Test methods take no arguments, commit no data to the database, and cannot send any emails.
• Strive for 100% code coverage. Do not focus on the 75% requirement.
• Write portable test methods and do not hardcode any Id or do not rely on some existing data.
• If possible don’t use seeAllData=true annotation
• Use System.assert methods to prove that code behaves properly.
• In the case of conditional logic (including ternary operators), execute each branch of code logic.
• Use the runAs method to test your application in different user contexts.
• Exercise bulk trigger functionality—use at least 20 records in your tests.
Best Practices

28. • Using static resource to mock Apex callout response
• Apex Test methods Best practices
Other resources

29. Go though Apex Testing module of Trailhead and earn your badge
Trailhead

30. Thank you