IETF Date in If-Modified-Since header

[dcore94]

I need to use the If-Modified-Since header in one of my APIs. The format requested is the IETF date format:

If-Modified-Since: Wed, 21 Oct 2015 07:28:00 GMT

as explained in [1].
Unfortunately this conflicts with the specification in [2] where it's stated that commas are separators for multi value parameters.
Is there any way out of this without having to join back the values manually?
M.
[1] https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Modified-Since
[2] http://exquery.github.io/exquery/exquery-restxq-specification/restxq-1.0-specification.html#form-header-annotation

[ChristianGruen]

Hi @adamretter, so you remember why the comma separation rule was added to the spec? Greetings!

[adamretter]

@ChristianGruen I don't remember exactly why that rule was chosen, but I suspect it was to enable easier handling of some other headers which are actually lists.

@dcore94 I don't think this should cause you any problems in practice, as you could do something like this:

declare
  %rest:GET
  %rest:path("/widget/{$id}")
  %rest:header-param("If-Modified-Since", "{$modified-since-header}")
function local:widget($id as xs:int, $modified-since-header as xs:string*) {
  let $modified-since := string-join($modified-since-header, ",")
  return
    <if-modified-since>{$modified-since}</if-modified-since>
};