1.明确目标
- 可以借助类，定义不同方法处理不同的步骤
- 应该借助队列，将请求的url放入队列处理
- 可以借助多个队列将请求，放回的html,抓取的内容都放在队列中，可以避免线程间的变量不安全问题，
上代码：
# -*- coding:utf-8 -*-
import requests
import time
from lxml import etree
from queue import Queue
import json
import threading
class Qiushi(object):
def __init__(self):
self.headers = {
"User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_5) AppleWeb\
Kit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36"
}
# 实例化三个队列，用来存放内容
self.url_queue = Queue()
self.html_queue = Queue()
self.content_queue = Queue()
def get_toal_url(self):
"""
获取所有的页面url,并且返回urllist
:return: urllist
"""
url_temp = "https://www.qiushibaike.com/8hr/page/{}/"
url_list = []
for i in range(1,36):
self.url_queue.put(url_temp.format(i))
def parse_url(self):
"""
一个发送请求，获取响应，同时etree处理html
:return:
"""
while self.url_queue.not_empty:
time.sleep(2)
url = self.url_queue.get()
print("开始发起请求 url:",url)
response = requests.get(url, headers=self.headers, timeout=10)#发起请求
html = response.content.decode()#获取html字符串
html = etree.HTML(html)#获取element 类型的html
self.html_queue.put(html)
# 这里可能队列数已经空了，但是消费者手里还有正在消费的队列
# 发出完成的信号，不发的话，join会永远阻塞，程序不会停止
self.url_queue.task_done()
def get_content(self):
"""
:param url:
:return: 一个list，包含一个url对应页面的所有段子的的所有内容的列表
"""
while self.html_queue.not_empty:
html = self.html_queue.get()
total_div = html.xpath('//div[@id="content-left"]/div')#返回divelememtn的一个列表
print(len(total_div))
items = []
for i in total_div:#遍历div标枪，获取糗事百科每条的内容的全部信息
author_name = i.xpath("./div[@class='author clearfix']/a[2]/h2/text()")[0].replace('\n','') if i.xpath("./div[@class='author clearfix']/a[2]/h2/text()") else "匿名用户"
# print(author_name)
if author_name != "匿名用户":
author_img = 'https:'+i.xpath("./div[@class='author clearfix']/a[1]/img/@src")[0]
author_href = "https://www.qiushibaike.com" +i.xpath("./div[@class='author clearfix']/a[2]/@href")[0]
author_gender = i.xpath('./div[@class="author clearfix"]//div/@class')[0].split(' ')[-1].replace("Icon", "")
author_age = i.xpath('./div[@class="author clearfix"]//div/text()')[0]
else:
author_img = None
author_href = None
author_gender = None
author_age = None
author_content = i.xpath('./a[1]/div[@class="content"]/span/text()')
author_vote = i.xpath('./div[@class="stats"]/span[1]/i/text()')[0].replace('\n', '') if i.xpath('./div[@class="stats"]/span[1]/i/text()')[0] else 0
author_comment = i.xpath('./div[@class="stats"]/span[2]/a/i/text()')[0].replace('\n', '')if i.xpath('./div[@class="stats"]/span[2]/a/i/text()') else 0
hot_comment_author = i.xpath('./a[@class="indexGodCmt"]/div/span[last()]/text()') if i.xpath('./a[@class="indexGodCmt"]/div/span[last()]/text()') else None
if hot_comment_author != None:
hot_comment = i.xpath('./a[@class="indexGodCmt"]/div/div/text()')[0].replace("\n：", "").replace("\n", "")
hot_comment_like_num = i.xpath('./a[@class="indexGodCmt"]//div[@class="likenum"]/text()')[0].replace("\n",'')
else:
hot_comment=None
hot_comment_like_num = None
item = dict(
author_name=author_name,
author_img=author_img,
author_href=author_href,
author_gender=author_gender,
author_age=author_age,
content=author_content,
content_vote=author_vote,
content_comment_numbers=author_comment,
hot_comment=hot_comment,
hot_comment_author=hot_comment_author,
hot_comment_like_num=hot_comment_like_num,
)
items.append(item)
self.content_queue.put(items)
self.html_queue.task_done()#task_done的时候，队列计数减一
def save_item(self):
"""
保存items
:params item:列表，
:return:
"""
while self.content_queue.not_empty:
items = self.content_queue.get()
f= open("qiubai.txt",'a',encoding='utf-8')
for i in items:
json.dump(i,f,ensure_ascii=False,indent=2)
f.close()
self.content_queue.task_done()
def run(self):
while 1:
# 1.获取 url list
# url_list = sel.get_total_url()
thread_list = []
thread_url = threading.Thread(target=self.get_toal_url)
# thread_url.start()
thread_list.append(thread_url)
#发起网络请求
for i in range(10):
thread_parse = threading.Thread(target=self.parse_url)
thread_list.append(thread_parse)
#提取数据
thread_get_content = threading.Thread(target=self.get_content)
thread_list.append(thread_get_content)
#保存
thread_save = threading.Thread(target=self.save_item)
thread_list.append(thread_save)
for t in thread_list:
print()
t.setDaemon(True) # 为每个进程设置为后台进程，效果是主进程退出子进程也会退出
t.start() #为了解决程序结束无法退出的问题
self.url_queue.join() # 让主线程等待，所有的队列为空的时候才能退出
self.html_queue.join()
self.content_queue.join()
time.sleep(600)
if __name__ == "__main__":
qiubai = Qiushi()
qiubai.run()
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