Adapt function iterates over all adapters calling them one by one (in reverse order) in a chained manner returning the result of the first adapter.

CORSHandler allows http to be served adding necessary headers to response.

Notify function adapts an http.Handler to write out “before” and “after” strings allowing the original http.Handler `h` to do whatever it was already going to do in between.

Adapter type function is a wrapper that takes in and returns an http.Handler.