Phillip Shipley continues his series looking at creating a client for the Nexmo API with his latest post, part four focusing on the testing of the current connections and state of the code.

At this point in this series we have a complete PHP client for the Nexmo APIs. Hopefully I’ve been able to teach some good practices and designs in the process of developing it, but I know many of you test-driven-development advocates are probably screaming that I’ve left out the most important part: testing, and testing early. Well, in order to keep these tutorials focused I’ve saved the testing to the end, and actually when testing API clients I find it easier to write the tests afterwards, but I’ll get into that later.

He points out that running tests on code that connects to APIs it a bit tricky as you don't want it to make actual API requests every time you run the tests. Instead he shows how to use Guzzle mock responses and the Mockable.io service (when you do actually need to test that HTTP requests are made). He includes the code examples to create the Guzzle mock response as well as a brief look at how to use Mockable along with your current tests with an "override" on the base URL.