Configurable implementation hidden behind a contract

Some concrete implementations are better to be hidden behind contracts, in a specific package. A layer of abstraction can save you later, mostly on unstable projects that often change requirements, or maybe you just want to test an idea, maybe you don’t have the necessary time to finish a task in a way you’d like to.

A good contract will save you. You can “throw” your implementation behind it and come back later to refine it. Sometimes later means in a few years. But if you’re behind a well designed contract, most probably you’re going to alter only the concrete implementation, without touching large areas of the projects.

I had to filter some user input. Some strings had to be HTML escaped, some sanitized to prevent different attacks. I’ve wrapped everything into a package, behind a contract. For escaping I’ve used Go’s html.EscapeString function, while for sanitizing I’ve found theĀ bluemonday package, which is inspired by an OWASP sanitizier for Java. Continue reading Configurable implementation hidden behind a contract