post-by-url-retrieve.el

;; HTTP POST by url-retrieve
;; ref: http://www.emacswiki.org/emacs/UrlPackage

(defun deferred:url-retrieve-post (url args &optional cbargs)
  (lexical-let ((nd (deferred:new)) 
                (url url) (args args)
                (cbargs cbargs) 
                buf)
    (deferred:next
      (lambda (x)
        (let ((url-request-method "POST")
              (url-request-extra-headers
               '(("Content-Type" . "application/x-www-form-urlencoded")))
              (url-request-data
               (mapconcat
                (lambda (arg)
                  (concat (url-hexify-string (car arg))
                          "="
                          (url-hexify-string (cdr arg))))
                args
                "&")))
          (setq buf 
                (url-retrieve 
                 url 
                 (lambda (xx) (deferred:post-task nd 'ok buf))
                 cbargs)))
        nil))
    nd))

(deferred:$
  (deferred:url-retrieve-post
    "http://127.0.0.1:8080/post-test.cgi"
    '(("a" . "test") ("param" . "OK")))
  (deferred:nextc it
    (lambda (buf)
      (insert (with-current-buffer buf (buffer-string)))
      (kill-buffer buf))))