Best way to mock out external web services while testing a web application in development

Question

Currently I am working on an application which depends on a lot of external web services. A few of them are authorize.net and chargify.

When testing(manual testing) things other than the integration with these web services, I replace these web service dependencies with fake versions of them which don't really do anything. The way I am doing it as of now, is by using the following line of code in the structure map registry class:

    For<IChargifyService>().Use<MockChargifyService>(); //uncomment this line to use a mock chargify service

I have similar lines in the registry for other fake services. I comment them out while deploying so that the real services are used in production. The real and fake service implementations are present in the Infrastructure assembly.

The problem with this approach is that I have to remember to uncomment the lines before deploying. I know there is a way to do this using Structure Xml Config, But I was wondering if there is a better way to do this. Would creating a Mock Infrastructure assembly be a good idea?

Answer 1

Take a look at Soap UI (Getting Started).

Answer 2

There are a couple ways I can think of:

1) You can create a separate assembly, as you suggested, that contains all of your mock implementations. You would also include a Registry in that assembly which sets the mock implementations as the defaults. The Registry in your main assembly would have to do a Scan that to optionally load your mock assembly - something like:

Scan(x =>
{
    x.TheCallingAssembly();
    x.AssembliesFromApplicationBaseDirectory();
    x.LookForRegistries();
});

2) Another option is to create a Profile for your mocks:

Profile("Test", x =>
{
    x.For<IChargifyService>().Use<MockChargifyService>();
    // etc.
});

Then somewhere in your application you would call:

ObjectFactory.Profile = "Test";

based on some environmental condition that indicates you are in test mode.