class ActionDispatch::FileHandler

(Content-Type, Content-Encoding) are returned.
If a matching file is found, the path and necessary response headers

in that order, including .br and .gzip compressed extensions.
Checks for +path+, +path+.html, and +path+/index.html files,

+public/+ directory (see Static#call).
Used by the +Static+ class to negotiate a servable file in the

Match a URI path to a static file to be served.

def find_file(path_info, accept_encoding:)
  each_candidate_filepath(path_info) do |filepath, content_type|
    if response = try_files(filepath, content_type, accept_encoding: accept_encoding)
      return response
    end
  end
end