Document `:path-info` and `:context`

[souenzzo]

ring-core provides a set of tools to manipulate path-info and context keys

But those keys are not mentioned in ring spec, or nowhere else

I think that worth mentioning it in some document.

[weavejester]

Those are primarily for integrating with Servlet containers. It would be a good idea to add a wiki page for them - I was actually surprised there wasn't one already.

[souenzzo]

Also, I'd like a feedback on this:

set-context behaves in an unexpeted way in "root" context

In my mind, it should: (request/set-context {:uri "/foo/bar"} "/") => {:uri "/foo/bar", :context "/", :path-info "/foo/bar"}

both context and path-info should follow the same spec as uri (never be empty, always start with /)

But it currently

(request/set-context {:uri "/foo/bar"} "")
=> {:uri "/foo/bar", :context "", :path-info "/foo/bar"} ;;1
(request/set-context {:uri "/foo/bar"} "/")
=> {:uri "/foo/bar", :context "/", :path-info "foo/bar"} ;;2

1. missing / in context
2. missing / in path-info

my proposal is to always remove the trailing / in context (inside set-context function)

;; POC impl - do not use
(defn set-context
  [request context]
  (let [context (string/replace context #"/+$" "")]
    (assoc request
      :context context
      :path-info (subs (:uri request) (count context)))))

[weavejester]

both context and path-info should follow the same spec as uri (never be empty, always start with /)

As I mentioned in my previous comment, these functions are primarily for integrating with Servlet containers. Their behavior is therefore set by how Servlets handle the context path and path info.