Cache variables in a session's cache per MarkLogic E-Node

e-node-session-cache.xqy

xquery version "1.0-ml";

declare function local:get-value($name as xs:string) {

  (: Make sure the $name is valid :)
  if (fn:string-length($name) le 0) then ()
  else
    (: Attempt to retrieve the value from the session variable :)
    if (xdmp:get-session-field($name)) then
      text{ "Cached:",xdmp:get-session-field($name)}
    else
      (: Save the header value into the session variable :)
      let $rqst-value := xdmp:get-request-header($name)
      return
        if (fn:string-length($rqst-value) le 0) then ()
        else
          text{ "Header:",xdmp:set-session-field($name, $rqst-value)}
};

<names> {
  for $x in xdmp:get-request-header-names()
  return <x name="{$x}">{local:get-value($x)}</x>
}</names>