【下载文档:  编写Python脚本批量下载DesktopNexus壁纸的教程.txt 】

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编写Python脚本批量下载DesktopNexus壁纸的教程
DesktopNexus 是我最喜爱的一个壁纸下载网站，上面有许多高质量的壁纸，几乎每天必上， 每月也必会坚持分享我这个月来收集的壁纸
但是 DesktopNexus 壁纸的下载很麻烦，而且因为壁纸会通过浏览器检测你当前分辨率来展示 合适你当前分辨率的壁纸，再加上是国外的网站，速度上很不乐观。
于是我写了个脚本，检测输入的页面中壁纸页面的链接，然后批量下载到指定文件夹中。
脚本使用 python 写的，所以需要机器上安装有 python 。
用法：
$ python desktop_nexus.py -p http://www.desktopnexus.com/tag/cat/ -s 1280x800 -o wallpapers
-p 包含 DesktopNexus 壁纸链接的页面，比如我的壁纸分享
-s 壁纸尺寸，可选，缺省为 1440x900
-o 壁纸输出的文件夹，可选，缺省为当前目录下的 wallpapers， 如果不存在会自动创建
代码：
#-*- coding: utf-8 -*-
from argparse import ArgumentParser
import os, re, sys
import urllib2, cookielib, urlparse
RE_WALLPAPER = r'http\:\/\/[^\/\.]+\.desktopnexus\.com\/wallpaper\/\d+\/'
CHUNK_SIZE = 1024 * 3
class DesktopNexus:
def __init__(self, page=None, size=None, output_dir=None):
self.page = page
self.size = size
self.output_dir = output_dir
def start(self):
print 'Making output directory:', self.output_dir
if not os.path.exists(self.output_dir):
os.makedirs(self.output_dir)
# Setup cookie
cookie = cookielib.CookieJar()
processer = urllib2.HTTPCookieProcessor(cookie)
opener = urllib2.build_opener(processer)
urllib2.install_opener(opener)
self._read_page()
def _get_pic_info(self, url):
pic_id = url.split('/')[-2]
html = urllib2.urlopen(url).read()
pattern = r'.*?)\"' % pic_id
match = re.search(pattern, html, flags=re.I|re.M|re.S)
if match:
return {'id': pic_id,
'token': match.group('token'),
'size': self.size}
else:
raise Exception('Cound not find wallpaper')
def _get_pic_file(self, pic_info):
redirect_url = 'http://www.desktopnexus.com/dl/inline/%(id)s/%(size)s/%(token)s' % pic_info
request = urllib2.urlopen(redirect_url)
return request.geturl()
def _download_pic(self, url):
pic_info = self._get_pic_info(url)
pic_file = self._get_pic_file(pic_info)
filename = os.path.split(urlparse.urlparse(pic_file).path)[-1]
filename = os.path.join(self.output_dir, filename)
with open(filename, 'wb') as output:
resp = urllib2.urlopen(pic_file)
total_size = int(resp.info().get('Content-Length'))
saved_size = 0.0
while saved_size != total_size:
chunk = resp.read(CHUNK_SIZE)
saved_size += len(chunk)
output.write(chunk)
self._print_progress('Saving file: %s' % filename, \
saved_size / total_size * 100)
def _print_progress(self, msg, progress):
sys.stdout.write('%-71s%3d%%\r' \
% (len(msg) <= 70 and msg or msg[:67] + '...', progress))
sys.stdout.flush()
if progress >= 100:
sys.stdout.write('\n')
def _read_page(self):
try:
print 'Fetching content:', self.page
html = urllib2.urlopen(self.page).read()
links = set(re.findall(RE_WALLPAPER, html, re.M|re.I))
count = len(links)
print 'Downloading wallpapers:'
for i, link in enumerate(links):
print '[%d/%d]: %s' % (i + 1, count, link)
try:
self._download_pic(link)
except Exception as e:
print 'Error downloading wallpaper.', e.message
except Exception as e:
print 'Error fetching content.', e
if __name__ == '__main__':
# Setup argparser
parser = ArgumentParser('python desktop_nexus.py')
parser.add_argument('-p', '--page', dest='page', required=True, \
help='specific a page that includes wallpaper list')
parser.add_argument('-s', '--size', dest='size', default='1440x900', \
help='specific the wallpaper size, default to 1440x900')
parser.add_argument('-o', '--output', dest='output_dir', default='wallpapers', \
help='specific the output directory, default to "wallpapers"')
args = parser.parse_args()
dn = DesktopNexus(**args.__dict__)
dn.start()