How to make unique short URL with Python?

Question

How can I make unique URL in Python a la http://imgur.com/gM19g or http://tumblr.com/xzh3bi25y When using uuid from python I get a very large one. I want something shorter f

Answer 1

This answer comes pretty late but I stumbled upon this question when I was planning to create an URL shortener project. Now that I have implemented a fully functional URL shortener(source code at amitt001/pygmy) I am adding an answer here for others.

The basic principle behind any URL shortener is to get an int from long URL then use base62(base32, etc) encoding to convert this int to a more readable short URL.

How is this int generated?

Most of the URL shortener uses some auto-incrementing datastore to add URL to datastore and use the autoincrement id to get base62 encoding of int.

The sample base62 encoding from string program:

# Base-62 hash

import string
import time

_BASE = 62


class HashDigest:
    """Base base 62 hash library."""

    def __init__(self):
        self.base = string.ascii_letters + string.digits
        self.short_str = ''

    def encode(self, j):
        """Returns the repeated div mod of the number.
        :param j: int
        :return: list
        """
        if j == 0:
            return [j]
        r = []
        dividend = j
        while dividend > 0:
            dividend, remainder = divmod(dividend, _BASE)
            r.append(remainder)
        r = list(reversed(r))
        return r

    def shorten(self, i):
        """
        :param i:
        :return: str
        """
        self.short_str = ""
        encoded_list = self.encode(i)
        for val in encoded_list:
            self.short_str += self.base[val]
        return self.short_str

This is just the partial code showing base62 encoding. Check out the complete base62 encoding/decoding code at core/hashdigest.py

All the link in this answer are shortened from the project I created