(defun rewrite-http-to-https (url)
  (if (eql 0 (search "http://" url))
      (concatenate 'string "https://"
                   (subseq url (length "http://")))
      url))

(defun drakma-fetch-to-file (url file)
  (let ((stream (drakma:http-request url :want-stream t :force-binary t))
        (temp-file (make-pathname :type "tmp"
                                  :defaults file))
        (buffer (make-array 10000 :element-type '(unsigned-byte 8))))
    (with-open-file (output-stream temp-file :direction :output
                                   :if-exists :rename-and-delete
                                   :element-type '(unsigned-byte 8))
      (loop
        (let ((last-index (read-sequence buffer stream)))
          (when (zerop last-index)
            ;; FIXME: doesn't work when FILE has no type already!
            (rename-file temp-file file)
            (return (probe-file file)))
          (write-sequence buffer output-stream :end last-index))))))

(defun ssl-fetch (url file &key follow-redirects quietly if-exists maximum-redirects)
  (declare (ignore follow-redirects quietly if-exists maximum-redirects))
  (drakma-fetch-to-file (rewrite-http-to-https url) file))

;; (setf ql-http:*fetch-scheme-functions* '(("http" . ssl-fetch)))