In this chapter, we discussed what an API is. Then, we looked at how we can use API proxies as contracts between ourselves and the consumers of our APIs. This protects our APIs from direct access by third parties. Next, we looked at a number of design guidelines for improving the quality of our APIs.
We then went on to discuss Swagger and saw how to document the Weather API with Swagger. Testing APIs was then covered, and we saw why it is good to test your code and any third-party code that you use in your projects. Finally, we looked at designing a language-agnostic API using RAML and translated it into a working project using C#.
In the next chapter, we will write a project to demonstrate securing keys using Azure Key Vault and securing our own API using API keys. But before then, let's put your brain to work to see what you have learned.
