Apex Developer Guide

Apex Developer Guide
Getting Started with Apex
Writing Apex
Running Apex
Invoking Apex
Apex Transactions and Governor Limits
Using Salesforce Features with Apex
Integration and Apex Utilities
Invoking Callouts Using Apex
Adding Remote Site Settings
Named Credentials as Callout Endpoints
SOAP Services: Defining a Class from a WSDL Document
Invoking HTTP Callouts
HTTP Classes
Testing HTTP Callouts
Testing HTTP Callouts by Implementing the HttpCalloutMock Interface
Testing HTTP Callouts Using Static Resources
Performing DML Operations and Mock Callouts
Using Certificates
Callout Limits and Limitations
Make Long-Running Callouts from a Visualforce Page
JSON Support
XML Support
Securing Your Data
Encoding Your Data
Using Patterns and Matchers
Debugging, Testing, and Deploying Apex
Apex Language Reference
Appendices
Glossary
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Testing HTTP Callouts by Implementing the HttpCalloutMock Interface

Provide an implementation for the HttpCalloutMock interface to specify the response sent in the respond method, which the Apex runtime calls to send a response for a callout.

  • The class that implements the HttpCalloutMock interface can be either global or public.
  • You can annotate this class with @isTest since it will be used only in test context. In this way, you can exclude it from your organization’s code size limit of 6 MB.

Note

Now that you have specified the values of the fake response, instruct the Apex runtime to send this fake response by calling Test.setMock in your test method. For the first argument, pass HttpCalloutMock.class, and for the second argument, pass a new instance of your interface implementation of HttpCalloutMock, as follows:

After this point, if an HTTP callout is invoked in test context, the callout is not made and you receive the mock response you specified in the respond method implementation.

To mock a callout if the code that performs the callout is in a managed package, call Test.setMock from a test method in the same package with the same namespace.

Note

This is a full example that shows how to test an HTTP callout. The interface implementation (MockHttpResponseGenerator) is listed first. It is followed by a class containing the test method and another containing the method that the test calls. The testCallout test method sets the mock callout mode by calling Test.setMock before calling getInfoFromExternalService. It then verifies that the response returned is what the implemented respond method sent. Save each class separately and run the test in CalloutClassTest.