Mirror Elpa (or Melpa or whatever)

mirror.el

;;;;;;;;;;
;; https://github.com/Zirak/mirror-elpa
;;;;;;;;;;

;; mirrors melpa into a ~packages~ subdirectory
;; you can run a web-server in said subdirectory and use it as a package archive

(defun read-archive (url)
  (with-temp-file (expand-file-name "archive-contents" "packages")
    (url-insert-file-contents (concat url "archive-contents"))
    (cdr (read (current-buffer)))))

(defun save-archive (base-url archive-name)
  (message (concat "Downloading " archive-name))

  (let ((file-name (expand-file-name archive-name "packages")))
    (if (file-exists-p file-name)
        (message (concat "Already have" archive-name))
        (url-copy-file (concat base-url archive-name) file-name))))

(defun get-full-package-name (package)
  ;; name-version.extension
  (concat
   (get-package-name package)
   "-"
   (get-package-version-string package)
   "."
   (get-package-extension package)))

(defun get-package-name (package)
  ;; (package-name ...)
  (symbol-name (car package)))

(defun get-package-version-string (package)
  ;; (package-name [(date version) ...])"
  (let ((version-tuple (elt (cdr package) 0)))
    (concat
     (number-to-string (car version-tuple))
     "."
     (number-to-string (elt version-tuple 1)))))

(defun get-package-extension (package)
  ;; (package-name . [(date version) something docstring package-type])"
  (let ((package-type (elt (cdr package) 3)))
    (cond ((eq package-type 'single) "el")
          ((eq package-type 'tar) "tar"))))

;; static void main
(setq melpa-url "http://melpa.org/packages/")

(unless (file-exists-p "packages")
  (make-directory "packages"))

(dolist (package (read-archive melpa-url))
    (save-archive melpa-url (get-full-package-name package)))

marmalade repo contains version tuples of length 1, line 36 needs to be replaced with:

(if (>= (length version-tuple) 2)
  (concat "." (number-to-string (elt version-tuple 1)))
  ""))))

Moved to https://github.com/Zirak/mirror-elpa