Python utility for converting Font Awesome cheatsheet to a JSON file

gen_fontawesome.py

"""
Generate fontawesome icon set in JSON format from website cheatsheet.
http://fortawesome.github.io/Font-Awesome/cheatsheet/

Usage: python gen_fontawesome.py
Output: font-awesome.json
{icon_name: entity_reference, ...}

Author: James Abney
Date: 2015-05-21
"""

import traceback
import json
import re
import urllib.request as http
from urllib.error import URLError
from bs4 import UnicodeDammit as UD
from bs4 import BeautifulSoup as Soup
from bs4.element import Tag as Tag

# Regular expression for reducing all spans
# of whitespace to a single space.
RE_WHITESPACE = re.compile(r'\s+')


def strip_excess_whitespace(string):
    """
    Return 'string' with newlines and excess spaces removed.
    """
    return RE_WHITESPACE.sub(' ', string).strip()


def fetch(url):
    """
    Fetch html from url.
    """
    if not url:
        return None

    try:
        html = None
        response = http.urlopen(url)
    except URLError:
        print('urlopen exception for url %s' % url)
        traceback.print_exc()
    else:
        # Get the byte stream from the http response.
        bytes_ = response.read()
        # Convert bytes to unicode text.
        html = UD(bytes_).unicode_markup
    return html


def generate_font_dict():
    """
    Fetch cheatsheet html, extract icon references,
    and convert to dictionary.
    """
    re_extract = re.compile(r'fa-([-a-z0-9]+)(?: \(alias\))? \[(&#x.+?;)\]')
    html = fetch('http://fortawesome.github.io/Font-Awesome/cheatsheet/')
    soup = Soup(html)
    container = soup.find('div', class_='row')

    icons = {}
    for child in container.children:
        if not isinstance(child, Tag):
            continue
        text = strip_excess_whitespace(child.get_text())
        match = re_extract.search(text)
        name = match.group(1)
        entity = match.group(2)
        icons[name] = entity
    return icons


def main():
    """
    Get dictionary of icon references and dump to JSON.
    """
    icons = generate_font_dict()
    with open('font-awesome.json', 'w') as icon_file:
        json.dump(icons, icon_file)


if __name__ == '__main__':
    main()