Secure a Web API

You want to enable HTTPS for your Web API, and you want to make sure that none of the developers forgets about this requirement. How do you do this?

Create an HttpsRequiredAttribute and add it to the global collection of attributes.
Create an HttpsRequiredAttribute and add it to each controller.
Create a custom ApiController base class from which all developers need to inherit.
Use MakeCert.exe to create an HTTPS certificate.