I'm a programmer who is passionate about Python programming, and I've recently been working on proxy server setup for Python crawlers, so today I'm going to share some of my insights and experiences on this topic.
Why do I need a proxy server?
First of all, we need to understand why we need to set up a proxy server when using Python crawlers. In the process of web crawling, sometimes we need to send frequent requests to the server, and if our requests are too frequent, they may be recognized by the server as malicious behavior and blocked. To avoid this problem, we can set up a proxy server to hide our real IP address to reduce the risk of being blocked.
How do I set up a proxy server?
Next, let's take a look at how to set up a proxy server in a Python crawler. First, we need to install a very useful third-party library called requests, which helps us send HTTP requests and supports proxy server settings.
Code Example:
"`ipipgothon
import requests
proxy = {
"http": "http://127.0.0.1:8888",
"https": "https://127.0.0.1:8888"
}
response = requests.get("http://www.example.com", proxies=proxy)
print(response.text)
“`
In the above example, we first imported the requests library and then created a dictionary called proxy that contains the address of the proxy server we want to use. Next, we sent a GET request using the requests.get() method and specified the proxy server we wanted to use via the proxies parameter. Finally, we printed out what the server returned.
Types of proxy servers
When setting up a proxy server, we also need to consider the type of proxy server. Common proxy server types include HTTP proxies, HTTPS proxies and SOCKS proxies, and in Python crawlers, we usually use HTTP proxies and HTTPS proxies.
Code Example:
"`ipipgothon
import requests
http_proxy = "http://127.0.0.1:8888"
https_proxy = "https://127.0.0.1:8888"
proxy = {
"http": http_proxy,
"https": https_proxy
}
response = requests.get("http://www.example.com", proxies=proxy)
print(response.text)
“`
In this example, we define the addresses of the HTTP proxy and the HTTPS proxy respectively, and set up the proxy servers accordingly.
Dynamic IP Proxy Pool
Apart from setting up a proxy server manually, we can also easily solve the problem of IP blocking by using Dynamic IP Proxy Pool. Dynamic IP Proxy Pooling is a technology that avoids being blocked by servers by constantly changing IP addresses.
Code Example:
"`ipipgothon
import requests
def get_proxy().
# Obtaining a Dynamic IP from a Proxy Pool
pass
proxy = {
"http": get_proxy(),
"https": get_proxy()
}
response = requests.get("http://www.example.com", proxies=proxy)
print(response.text)
“`
In the above example, we defined a function called get_proxy() to get the address of a proxy server from a pool of dynamic IP proxies and set it as an HTTP and HTTPS proxy.
summarize
Through the introduction of this article, I hope you can understand how to set up a proxy server in Python crawler and master the related tips and tricks. In the actual development, setting up a proxy server is very important, it can help us avoid the risk of being blocked, so as to be more stable and efficient web crawling. I hope this article can help you, thank you!