sourceafButter::StickyHeadersMiddleware.fan

** (Middleware) - Automatically sets headers in each request, so you don't have to!
** 
** Only non-existing header values are set, leaving any existing values untouched. This means you can use sticky 
** headers to set default values and manually override them for individual requests.
class StickyHeadersMiddleware : ButterMiddleware {

    ** The header values set in every request 
    HttpRequestHeaders stickyHeaders    := HttpRequestHeaders()
    
    @NoDoc
    override ButterResponse sendRequest(Butter butter, ButterRequest req) {     
        stickyHeaders.map.each |val, key| {
            if (!req.headers.containsKey(key))
                req.headers[key] = val
        }
        
        return butter.sendRequest(req)
    }
}