UrlCache

Complexity

Total Complexity

10

Size/Duplication

Total Lines	43
Duplicated Lines	0 %

Importance

Changes

0

2 Methods

Rating	Name	Duplication	Size	Complexity
A	md5url()	0	6	3
B	get_file_url()	0	23	5

import hashlib
import threading
from os import path

from django import template

from chat.settings import STATIC_URL, STATIC_ROOT, logging, DEBUG

register = template.Library()
logger = logging.getLogger(__name__)

md5_cache = {}


@register.simple_tag
def md5url(file_name):
	value = md5_cache.get(file_name)
	if value is None or DEBUG:
		value = get_file_url(file_name)
	return value


def get_file_url(file_name):
	entry_name = file_name
	try:
		key = '#root#'
		if key in file_name:
			file_name = file_name.split(key, 1)[1]
			file_path = path.join(STATIC_ROOT, entry_name.replace(key, ''))
			prefix = ''
		else:
			file_path = path.join(STATIC_ROOT, file_name)
			prefix = STATIC_URL

		md5 = calculate_file_md5(path.join(STATIC_ROOT, file_path))[:8]
		value = '%s%s?v=%s' % (prefix, file_name, md5)
		logger.info("Caching url '%s' for file '%s'", value, file_name)
	except Exception as e:
		if hasattr(e, 'errno') and e.errno == 21:  # is a directory
			value = STATIC_URL + file_name
			logger.warning("Caching url '%s' for directory %s", value, file_name)
		else:
			raise Exception('Unable to calculate md5 for {} because {}', file_name, e)
	md5_cache[entry_name] = value
	return value


def calculate_file_md5(file_path):
	with open(file_path, 'rb') as fh:
		m = hashlib.md5()
		while True:
			data = fh.read(8192)
			if not data:
				break
			m.update(data)
		return m.hexdigest()