anchor.diff:    3. CONTENT-LENGTH - Declared content length for the incoming data."
     (multiple-value-bind (response status-code headers fourth fifth must-close-p)
         (http-request (strcat (server-uri (database-server db))
  +                            "/"
                               (database-name db)
  +                            "/"
                               (url-encode (princ-to-string doc-id))
  +                            "/"
                               attachment-name)
                       :want-stream t)
       (declare (ignore fourth fifth))
  
positive.code:     (case (or (cdr (assoc status-code +status-codes+ :test #'=))
                (error "Unknown status code: ~A. HTTP Response: ~A"
                       status-code response))
        (:ok (data->json (database-server db) response))
        (:not-found (error 'document-not-found :db db :id doc-id))
        (otherwise (error 'unexpected-response :status-code status-code :response response)))))
  
  
negative.code: The CONTENT-TYPE should be a string specifying the content type for DATA."
    (multiple-value-bind (response status-code)
        (http-request (strcat (server-uri (database-server db))
                              "/"
                              (database-name db)
                              "/"
                              (url-encode (princ-to-string doc-id))
                              "/"
                              attachment-name)
                      :method :put
                      :parameters (when rev
  