ENIGMA CURRY

Shortened URLs in Emacs using is.gd (like tinyurl)

I've casually been teaching myself emacs lisp lately. Today I wrote a utility that shortens long urls within regions using the http://is.gd URL shortening service. There's plenty of existing code out there that is more lisp like, but this is supposed to be a learning experience for me so I did it myself. I like python and so I used python for most of the heavy lifting.

I created a directory to hold all of my emacs specific python functions: ~/.emacs.d/ryan-pymacs-extensions

I wrote the following python function, shorten_url.py in that directory:

!/usr/bin/env python
# -*- coding: utf-8 -*-

__author__ = "Ryan McGuire (ryan@enigmacurry.com)"
__date__   = "Mon Sep 15 12:27:14 2008"

import doctest
import urllib2
import re

def shorten_with_is_gd(url):
    """Shorten a URL with is.gd

    >>> shorten_with_is_gd('http://www.enigmacurry.com')
    'http://is.gd/FFP'

    """
    u = urllib2.urlopen("http://is.gd/api.php?longurl="+url)
    return u.read()

def shorten_in_text(text):
    """Shorten all the urls found inside some text

    >>> shorten_in_text('Hi from http://www.enigmacurry.com')
    'Hi from http://is.gd/FFP'

    """
    replacements = {} #URL -> is.gd URL
    #Only check for urls that start with "http://" for now
    for m in re.finditer("http://[^ \n\r]*", text):
        try:
            replacements[m.group()] = shorten_with_is_gd(m.group())
        except:
            replacements[m.group()] = m.group()
    for url,replacement in replacements.items():
        text = text.replace(url, replacement)
    return text

if __name__ == '__main__':
    doctest.testmod(verbose=True)

and the following lisp makes "M-x shorten-url" do the rest of the replacement work:

;add ~/.emacs.d/ryan-python-extensions to python path
(pymacs-exec "import sys, os")
(pymacs-exec "sys.path.append(os.path.join(os.path.expanduser('~'),'.emacs.d','ryan-pymacs-extensions'))")

;;Shorten URLs with is.gd
(pymacs-exec "import shorten_url")
(defun shorten-url (start end)
  (interactive "r")
  (let ((region (buffer-substring start end)))
    (let ((rt (pymacs-eval (format "shorten_url.shorten_in_text('''%s''')" region))))
      (kill-region start end)
      (insert rt)
      )
  ))