练习之代码片段,以做备忘:
# encoding=utf8
from __future__ import unicode_literals
import urllib, urllib2
import re
import os
import threading
def get_html(url):
try:
url = url.encode('utf-8')
page = urllib2.urlopen(url)
return page.read()
except Exception as ex:
print 'get url_%s html error, ex=%s' % (url, ex)
def get_images(url):
url = url.encode('utf-8')
html = get_html(url)
pattern = r'<img.+class="BDE_Image".+src="([^"]+\.jpg)"'
img_list = re.findall(pattern, html)
pattern = r'<img.+src="([^"]+\.jpg)".+class="BDE_Image"'
img_list.extend(re.findall(pattern, html))
# 去重
img_list = sorted(set(img_list), key=img_list.index)
return img_list
# 指定主题页面之总页面数
def get_page_count(url):
html = get_html(url)
pattern = r'"total_page":(\d+)'
m = re.search(pattern, html)
return m.group(1) if m else 0
# 获取每页主题url列表
def get_page_urls(html):
pattern = r'<a href="/p/(\d+)"'
url_list = re.findall(pattern, html)
if url_list:
url_list = map(lambda x: 'https://tieba.baidu.com/p/%s' % x, url_list)
return url_list
# 下载指定页面之图片
def download_page_images(page_url):
html = get_html(page_url)
title = re.search(r'(?<=<title>)(.*)(?=</title>)', html).group(1)
print title
page_no = re.search(r'(\d+)', page_url).group(0)
page_count = int(get_page_count(page_url))
print 'page: %s, page_count: %d' % (page_no, page_count)
for page_idx in range(1, page_count + 1):
url = page_url + '?pn=%d' % page_idx
img_list = get_images(url)
if img_list:
print 'page index: %d, image_count: %d' % (page_idx, len(img_list))
if not os.path.exists('images'):
os.mkdir('images')
img_folder = 'images\%s' % page_no
if not os.path.exists(img_folder):
os.mkdir(img_folder)
idx = 0
for img_url in img_list:
img_filename = img_folder + '\%d_%d.jpg' % (page_idx, idx)
if not os.path.exists(img_filename):
urllib.urlretrieve(img_url, img_filename)
idx += 1
def main():
# 扒取最大页数
max_pagecount = 30
base_url = r'https://tieba.baidu.com/f?kw=图片&ie=utf-8?pn=%s'
# 分页而扒
for idx in range(1, max_pagecount):
url = base_url % ((idx - 1) * 50)
html = get_html(url)
url_list = get_page_urls(html)
for page_url in url_list:
try:
download_page_images(page_url)
threading._sleep(2)
except:
continue
if __name__ == '__main__':
main()