fmt/support/download.py
Victor Zverovich 950e6b9753 Fix downloader
2015-02-12 21:34:36 -08:00

47 lines
1.3 KiB
Python

# A file downloader.
import contextlib, os, tempfile, timer, urllib2, urlparse
class Downloader:
def __init__(self, dir=None):
self.dir = dir
# Downloads a file and removes it when exiting a block.
# Usage:
# d = Downloader()
# with d.download(url) as f:
# use_file(f)
def download(self, url, cookie=None):
suffix = os.path.splitext(urlparse.urlsplit(url)[2])[1]
fd, filename = tempfile.mkstemp(suffix=suffix, dir=self.dir)
os.close(fd)
with timer.print_time('Downloading', url, 'to', filename):
opener = urllib2.build_opener()
if cookie:
opener.addheaders.append(('Cookie', cookie))
num_tries = 2
for i in range(num_tries):
try:
f = opener.open(url)
except urllib2.URLError, e:
print('Failed to open url', url)
continue
length = f.headers.get('content-length')
if not length:
print('Failed to get content-length')
continue
length = int(length)
with open(filename, 'wb') as out:
count = 0
while count < length:
data = f.read(1024 * 1024)
count += len(data)
out.write(data)
@contextlib.contextmanager
def remove(filename):
try:
yield filename
finally:
os.remove(filename)
return remove(filename)