怎样使用python爬虫获得免费代理IP
爬虫一直是python使用的一个重要部分，而许多网站也为此做了许多反爬措施，其中爬虫访问过于频繁直接封ip地址也作为一种“伤敌一千，自损八百”的方法被许多网站采用，代理ip便可以防止这种情况出现。
进行爬取和测试有效性
分析完毕开始爬取ip，直接使用第三方的requests和BeautifulSoup4，可以让抓取变得很方便，代码如下：
from iptools import header, dict2proxy
from bs4 import BeautifulSoup as Soup
def parse_items(items):
# 存放ip信息字典的列表
ips = []
for item in items:
tds = item.find_all('td')
# 从对应位置获取ip，端口，类型
ip, port, _type = tds[1].text, int(tds[2].text), tds[5].text
ips.append({'ip': ip, 'port': port, 'type': _type})
return ips
def check_ip(ip):
try:
proxy = dict2proxy(ip)
url = 'https://www.ipip.net/'
r = requests.get(url, headers=head, proxies=pro,timeout=5)
r.raise_for_status()
except:
return False
else:
return True
def get_proxies(index):
url = 'http://zhimaruanjian.com// % index
r = requests.get(url, headers=header)
r.encoding = r.apparent_encoding
r.raise_for_status()
soup = Soup(r.text, 'lxml')
# 第一个是显示最上方的信息的，需要丢掉
items = soup.find_all('tr')[1:]
ips = parse_items(items)
good_proxies = []
for ip in ips:
if check(ip):
good_proxies.append(ip)
return good_proxies
就像在上面写的，有效性我直接使用了ip查询网站，获得的ip基本确保可以直接使用。
写入json文件
可以将获取的ip存放在json文件中，json模块的使用也很简单，直接打开一个文件，使用dump方法写入文件即可
import json
def write_to_json(ips):
with open('proxies.json', 'w', encoding='utf-8') as f:
json.dump(ips, f, indent=4)
写入MongoDB
写入数据库后获取和操作会很方便
from pymongo import MongoClient as Client
def write_to_mongo(ips):
client = Client(host='localhost', port=27017)
db = client['proxies_db']
coll = db['proxies']
for ip in ips:
if coll.find({'ip': ip['ip']}).count() == 0:
coll.insert_one(ip)
client.close()
写入后使用RoboMongo查看
使用多线程
导入threading包，将Thread封装一下，得到最终的代码
get_proxies.py
import json
import requests
import time
from proxies_get.iptools import header, dict2proxy
from bs4 import BeautifulSoup as Soup
from pymongo import MongoClient as Client
import threading
def parse_items(items):
# 存放ip信息字典的列表
ips = []
for item in items:
tds = item.find_all('td')
# 从对应位置获取ip，端口，类型
ip, port, _type = tds[1].text, int(tds[2].text), tds[5].text.lower()
ips.append({'ip': ip, 'port': port, 'type': _type})
return ips
def check_ip(ip, good_proxies):
try:
pro = dict2proxy(ip)
# print(pro)
url = 'https://www.ipip.net/'
r = requests.get(url, headers=header, proxies=pro, timeout=5)
r.raise_for_status()
print(r.status_code, ip['ip'])
except Exception as e:
# print(e)
pass
else:
good_proxies.append(ip)
def write_to_json(ips):
with open('proxies.json', 'w', encoding='utf-8') as f:
json.dump(ips, f, indent=4)
def write_to_mongo(ips):
'''将数据写入mongoDB'''
client = Client(host='localhost', port=27017)
db = client['proxies_db']
coll = db['proxies']
# 先检测，再写入，防止重复
for ip in ips:
if coll.find({'ip': ip['ip']}).count() == 0:
coll.insert_one(ip)
client.close()
class GetThread(threading.Thread):
'''对Thread进行封装'''
def __init__(self, args):
threading.Thread.__init__(self, args=args)
self.good_proxies = []
def run(self):
url = 'http://zhimaruanjian.com/ % self._args[0]
# 发起网络访问
r = requests.get(url, headers=header)
r.encoding = r.apparent_encoding
r.raise_for_status()
soup = Soup(r.text, 'lxml')
# 第一个是显示最上方的信息的，需要丢掉
items = soup.find_all('tr')[1:]
ips = parse_items(items)
threads = []
for ip in ips:
# 开启多线程
t = threading.Thread(target=check_ip, args=[ip, self.good_proxies])
t.start()
time.sleep(0.1)
threads.append(t)
[t.join() for t in threads]
def get_result(self):
return self.good_proxies
if __name__ == '__main__':
# 主函数使用多线程
threads = []
for i in range(1, 30):
t = GetThread(args=[i])
t.start()
time.sleep(10)
threads.append(t)
[t.join() for t in threads]
for t in threads:
proxies = t.get_result()
write_to_mongo(proxies)
iptools.py
header = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) '
'AppleWebKit/537.36 (KHTML, like Gecko) '
'Chrome/64.0.3282.186 Safari/537.36'}
def dict2proxy(dic):
s = dic['type'] + '://' + dic['ip'] + ':' + str(dic['port'])
return {'http': s, 'https': s}
总结
这个免费代理ip的爬虫没什么太难的地方，就是服务器有点弱，一不小心就503了，需要限制一下访问速度。使用免费的代理会影响使用到的效果，因此可以使用代理商代理ip服务，会更加的稳定安全。