Python基于分析Ajax请求实现抓取今日头条街拍图集功能示例

本文实例讲述了Python基于分析Ajax请求实现抓取今日头条街拍图集功能。分享给大家供大家参考，具体如下：

代码:

import os
import re
import json
import time
from hashlib import md5
from multiprocessing import Pool
import requests
from requests.exceptions import RequestException
from pymongo import MongoClient
# 配置信息
OFFSET_START = 0  # 爬去页面的起始下标
OFFSET_END = 20  # 爬去页面的结束下标
KEYWORD = '街拍'  # 搜索的关键字
# mongodb相关配置
MONGO_URL = 'localhost'
MONGO_DB = 'toutiao'  # 数据库名称
MONGO_TABLE = 'jiepai' # 集合名称
# 图片保存的文件夹名称
IMAGE_PATH = 'images'
headers = {
  "User-Agent": 'Mozilla/5.0 (Windows NT 10.0; Win64; x64)'
}
client = MongoClient(host=MONGO_URL)
db = client[MONGO_DB]
jiepai_table = db[MONGO_TABLE]
if not os.path.exists(IMAGE_PATH):
  os.mkdir(IMAGE_PATH)
def get_html(url, params=None):
  try:
    response = requests.get(url, params=params, headers=headers)
    if response.status_code == 200:
      return response.text
    return None
  except RequestException as e:
    print("请求%s失败: " % url, e)
    return None
# 获取索引页内容
def get_index_page(offset, keyword):
  basic_url = 'http://www.toutiao.com/search_content/'
  params = {
    'offset': offset,
    'format': 'json',
    'keyword': keyword,
    'autoload': 'true',
    'count': 20,
    'cur_tab': 3
  }
  return get_html(basic_url, params)
def parse_index_page(html):
  '''
  解析索引页内容
  返回: 索引页中包含的所有详情页url
  '''
  if not html:
    return
  data = json.loads(html)
  if 'data' in data:
    for item in data['data']:
      article_url = item['article_url']
      if 'toutiao.com/group' in article_url:
        yield article_url
# 获取详情页
def get_detail_page(url):
  return get_html(url)
# 解析详情页
def parse_detail_page(url, html):
  '''
    解析详情页
    返回对应的标题，url和包含的图片url
  '''
  title_reg = re.compile('<title>(.*?)</title>')
  title = title_reg.search(html).group(1)
  gallery_reg = re.compile('var gallery = (.*?);')
  gallery = gallery_reg.search(html)
  if gallery and 'sub_images' in gallery.group(1):
    images = json.loads(gallery.group(1))['sub_images']
    image_list = [image['url'] for image in images]
    return {
      'title': title,
      'url': url,
      'images': image_list
    }
  return None
def save_to_mongodb(content):
  jiepai_table.insert(content)
  print("存储到mongdob成功", content)
def download_images(image_list):
  for image_url in image_list:
    try:
      response = requests.get(image_url)
      if response.status_code == 200:
        save_image(response.content)
    except RequestException as e:
      print("下载图片失败: ", e)
def save_image(content):
  '''
    对图片的二进制内容做hash，构造图片路径,以此保证图片不重复
  '''
  file_path = '{0}/{1}/{2}.{3}'.format(os.getcwd(),
                     IMAGE_PATH, md5(content).hexdigest(), 'jpg')
  # 去除重复的图片
  if not os.path.exists(file_path):
    with open(file_path, 'wb') as f:
      f.write(content)
def jiepai(offset):
  html = get_index_page(offset, KEYWORD)
  if html is None:
    return
  page_urls = list(parse_index_page(html))
  # print("详情页url列表:" )
  # for page_url in page_urls:
  #   print(page_url)
  for page in page_urls:
    print('get detail page:', page)
    html = get_detail_page(page)
    if html is None:
      continue
    content = parse_detail_page(page, html)
    if content:
      save_to_mongodb(content)
      download_images(content['images'])
      time.sleep(1)
  print('-------------------------------------')
if __name__ == '__main__':
  offset_list = range(OFFSET_START, OFFSET_END)
  pool = Pool()
  pool.map(jiepai, offset_list)

备注:

其实通过url请求返回的json数据中已经包含了图片列表

import requests
basic_url = 'http://www.toutiao.com/search_content/?offset={}&format=json&keyword=%E8%A1%97%E6%8B%8D&autoload=true&count=20&cur_tab=3'
url = basic_url.format(0)
html = requests.get(url).json()
items = html['data']
for item in items:
  title = item['media_name']
  image_list = [image_detail['url'] for image_detail in item['image_detail']]
  print(title, image_list)

希望本文所述对大家Python程序设计有所帮助。