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'<a href="/get/%s/?t=(?P<token>.*?)"' % 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()