In this era of information explosion, data is like the modern "gold". And python crawler is we dig these gold "shovel". However, the crawler in the crawl data, often encounter IP blocked, this time, the proxy IP is particularly important. Today, I will talk to you about how to use proxy IP in Python crawler to ensure that our crawler can successfully "mining".

What is a proxy IP?

Proxy IP, as the name suggests, is the IP address of a proxy server. It is like a middleman, when we send requests to the target website through crawlers, the proxy IP will visit the target website for us and then forward the returned data to us. In this way, the target website will not know our real IP, thus avoiding the risk of IP blocking.

Why do I need a proxy IP?

In the world of crawlers, IP blocking is a common occurrence. In order to prevent frequent visits, target websites usually set up some anti-crawler mechanisms, such as limiting the frequency of visits from the same IP. When our crawler visits the target website frequently, it may trigger these mechanisms, resulting in IP blocking. Using a proxy IP can effectively bypass these restrictions and allow the crawler to continue to work smoothly.

How do I get a proxy IP?

There are many ways to get proxy IPs, the common ones are free proxy IPs and paid proxy IPs. free proxy IPs don't cost any money, but the quality varies and there may be a lot of unavailable IPs, whereas paid proxy IPs are relatively stable and reliable, but they cost a certain amount of money.

Here, I recommend a popular proxy IP site:

• IPIPGO (ipipgo.com)

How to use proxy IP in Python?

Next, we'll look at how to use proxy IPs in Python. here, we'll use the requests library as an example to demonstrate how to set up a proxy IP.

First, install the requests library:

pip install requests

Then, write the code:

import requests

# Setting proxy IP
proxies = {
'http': 'http://123.456.789.0:8080',
'https': 'https://123.456.789.0:8080',
}

# Sending a request using a proxy IP
response = requests.get('http://httpbin.org/ip', proxies=proxies)

print(response.text)

In the above code, we pass the proxy IP to the requests.get method by setting the proxies parameter. This way, the requests library will use the proxy IP to access the target website.

How do I verify the validity of a proxy IP?

Before using a proxy IP, we need to verify its validity. Here, we can write a simple function to check if the proxy IP is available.

def check_proxy(proxy).
try: response = requests.get('', proxies=proxy, timeout=5)
response = requests.get('http://httpbin.org/ip', proxies=proxy, timeout=5)
if response.status_code == 200: print(f "Proxy {proxy_http']}
print(f "Proxy {proxy['http']} is valid")
return True
else: print(f "Proxy {proxy['http']} is valid")
print(f "Proxy {proxy['http']} is invalid")
return False
except: print(f "Proxy {proxy['http']} is invalid")
print(f "Proxy {proxy['http']} is invalid")
return False

# Example proxy IP
proxy = {
'http': 'http://123.456.789.0:8080',
'https': 'https://123.456.789.0:8080',
}

# Verify the proxy IP
check_proxy(proxy)

In the above code, we have defined a check_proxy function to check if the proxy IP is valid. If the proxy IP is available, the function returns True; otherwise, it returns False.

How to manage a large number of proxy IPs?

In practice, we may need to manage a large number of proxy IPs. to make it easier, we can store the proxy IPs in a database, such as SQLite, and then write code to read the available proxy IPs from the database.

First, install the SQLite library:

pip install sqlite3

Then, write the code:

import sqlite3

# Create a database connection
conn = sqlite3.connect('proxies.db')
cursor = conn.cursor()

# Create a table
cursor.execute('''CREATE TABLE IF NOT EXISTS proxies
(id INTEGER PRIMARY KEY, ip TEXT, port TEXT, is_valid INTEGER)''')

# Insert Proxy IP
cursor.execute("INSERT INTO proxies (ip, port, is_valid) VALUES ('123.456.789.0', '8080', 1)")

# Query available proxy IPs
cursor.execute("SELECT ip, port FROM proxies WHERE is_valid=1")
proxies = cursor.fetchall()

# Print available proxy IPs
for proxy in proxies:
print(f "http://{proxy[0]}:{proxy[1]}")

# Close the database connection
conn.commit()
conn.close()

In the above code, we first created a SQLite database and created a proxies table for storing proxy IPs. then, we inserted a proxy IP record and queried for all available proxy IPs.

summarize

Overall, proxy IP is a very important part of Python crawler. By using proxy IP, we can effectively avoid IP blocking and improve the stability and efficiency of the crawler. I hope today's tutorial can help you better understand and use proxy IP, so that your crawler journey is smoother!