When we use css-sprites it's important to make browser cache them for longest period possible. On other hand, we need to refresh them when they are updated. This is especially visible when all icons are stored in single sprite. When it's outdated - entire site becomes ugly.
To solve this task I've implemented this small script that adds file's hash to url:
background-image: url(images/icons.png);
background-image: url(images/icons.png?a3844c660);#!/usr/bin/python
import os.path
import re
import hashlib
def file_hash(filename, block_size=2**20):
md5 = hashlib.md5()
with open(filename, 'rb') as f:
for data in iter(lambda: f.read(block_size), ''):
md5.update(data)
return md5.hexdigest()
def find_replace(match, basedir):
match = match.replace("'", '')
if '?' in match or '#' in match or match.startswith('http://'):
print 'skipping: ', match
return None
filename = os.path.join(basedir, match)
return '%s?%s' % (match, file_hash(filename)[:10])
def insert_hash(filename, debug=False):
basedir = os.path.dirname(filename)
css = open(filename).read()
matches = re.findall(r"url\((.*?)\)", css)
replacements = dict([
(match, find_replace(match, basedir))
for match in matches
])
if debug:
for key, value in replacements.iteritems():
print key, ' => ', value
else:
for match, repl in replacements.iteritems():
if repl:
css = css.replace(match, repl)
out = open(filename, 'w')
out.write(css)
out.close()
if __name__ == '__main__':
from optparse import OptionParser
usage = 'usage: %prog filename.css'
parser = OptionParser(usage=usage)
parser.add_option("", "--debug", action="store_true", dest="debug", default=False,
help="When set, just output list of substitutions.")
(options, args) = parser.parse_args()
if len(args) < 1:
print 'You must provide file name.'
insert_hash(os.path.realpath(args[0]), options.debug)Update
This is pretty old article. Now it's better to use something integrated to your build process - grunt, webassets, etc.
Subscribe for the news and updates
This article explores Figma’s Dev Mode, a tool that streamlines design-to-code translation by enabling precise inspection, automated code generation, and seamless integration with design systems.
SQL is a fairly complicated language with a steep learning curve. For a large number of people who make use of SQL, learning to apply it efficiently takes lots of trials and errors. Here are some tips on how you can make your SELECT queries better. The majority of tips should be applicable to any relational database management system, but the terminology and exact namings will be taken from PostgreSQL.
This article is aimed for beginners, who are trying to choose between Ruby on Rails and Django. Let’s see which is fastest and why.
In this article we will tell you about the basics of working with GraphQL in Angular 2 environment with detailed example.
In order to check if user is authentcated in test, you can run:
As you know, model managers can be overriden in Django. It's convenient to add custom filtration method.