Tim Lytle: HTTP Patterns: PSR 7 & 15 By Example
Details
Chances are your code already uses one of the HTTP PSRs in some way. In this 'no slides, just code' session we'll take a hands on look at how HTTP Messages (PSR-7) and HTTP Handlers (PSR-15) work, and how they can be properly leveraged.
HTTP messages provide a considerable advantage over global variables, and their immutability actually makes it easier to confidently modify an incoming request or an outgoing response in your web application.
HTTP handlers are a common concept in micro-frameworks, and PSR-15 provides a way to create reusable framework-agnostic code. But that's not all it provides. The HTTP handler interface can be used to inject the concept of middleware into an existing application without having to introduce a new framework. Or to easily build a lightweight application without any framework.
Take a guided tour through both PSRs, and find out how you can used them effectively in your current codebase.