Compile a Python script to download topnexus wallpapers in batches-Python tutorial

This article mainly introduces how to compile Python scripts to download the topnexus wallpaper in batches. Compared with common crawler crawlers, this article's download wallpaper tutorial also includes the implementation of setting the resolution to be downloaded, for more information, see topnexus, my favorite wallpaper download website. There are many high-quality wallpapers on it, which are required almost every day. every month, I will always share my wallpapers collected this month.

However, downloading the ghost topnexus wallpaper is troublesome, and because the wallpaper will detect your current resolution in a browser to display the wallpaper that suits your current resolution, coupled with a foreign website, the speed is not optimistic.

So I wrote a script to check the links on the wallpaper page on the input page, and then download them to the specified folder in batches.

The script is written in python, so python must be installed on the machine.
Usage:

$ python desktop_nexus.py -p http://www.desktopnexus.com/tag/cat/ -s 1280x800 -o wallpapers

-P: a page that contains links to topnexus wallpapers, such as my wallpaper sharing
-S wallpaper size (optional). The default value is 1440x900.
-O: The output folder of the wallpaper. optional. the default folder is wallpapers in the current directory. if the folder does not exist, it is automatically created.

Code:

#-*- coding: utf-8 -*-from argparse import ArgumentParserimport os, re, sysimport urllib2, cookielib, urlparseRE_WALLPAPER = r'http\:\/\/[^\/\.]+\.desktopnexus\.com\/wallpaper\/\d+\/'CHUNK_SIZE = 1024 * 3class 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.', eif __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()