Python HTTP Proxy: Homemade Proxy Server Tutorial

Hands-on with Python to rub an HTTP proxy parser!

Recently, a lot of buddies doing data crawling asked me, using Python to build its own proxy server in the end is not reliable? It's like pickling your own pickles at home, it all depends on the quality of the ingredients. Today we take Python comes with a socket library to start, teach you the whole of a proxy service can actually run up, and incidentally talk about professional proxy service providers ipipgo those who save the heart of the game.

What's the deal with proxy services?

For example, if you want a courier to help you pick up a package, the proxy server is the middleman. The biggest difference between a regular courier (direct connection) and a proxy pickup service (proxy) is thatThere's an extra stopover in the middle.. You have to deal with the mess if you build it yourself:

Proxy Service Core Code for Python

Let's start with the basics and build a shelf with sockets:

import socket

def start_proxy(port=8888): server = socket.socket(socket.AF_INET, socket.
    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server.bind(('', port))
    server.listen(5)
    print(f "Proxy squatting on port {port}...")

    while True: client, addr = server.accept
        client, addr = server.accept()
        data = client.recv(4096)
         Here we parse the HTTP headers to find the target address
        target_host = parse_host(data)
        forward_request(client, target_host, data)

def parse_host(data).
     Strip the Host field from the HTTP headers.
    headers = data.decode().split('r')
    for h in headers.
        if h.startswith('Host:'):: return h.split(').
            return h.split(' ')[1].strip()
    return None

This code is a rough house, really want to live in people still need to decorate. For example, when encountering HTTPS requests, it will stop, long time connection is easy to drop the line, these pitfalls we will talk about later.

Putting the hard stuff on agency services

If you want to make a self-built agent work, you can't go wrong with these optimizations:

1. Timeout retry mechanism:Network jerks are common, set it up to retry if it doesn't respond for 3 seconds

2. Request filtering:Don't forward everything. Block unconventional ports.

3. Logging:You have to keep a notebook of who's been here and what they've done.

 Optimized forwarding function
def forward_request(client, target_host, data).
    try: target = socket.
        target = socket.create_connection((target_host, 80), timeout=3)
        target.sendall(data)

        while True: resp = target.recv(40)
            target.sendall(data) while True: resp = target.recv(4096)
            if not resp: break
            client.send(resp)

    except Exception as e.
        print(f "Rollover: {str(e)}")
    finally: target.close()
        target.close()
        client.close()

What's the best way to choose between self-built vs. professional agency?

Tossing your own proxies is like driving a walk-behind tractor, while using ipipgo is like driving an automatic Tesla:

- Need to deal with CAPTCHA? ipipgo'sDynamic session holdIt's self-renewing.
- High Frequency Access Blocked? TheirIP Rotation SystemThousands of IPs per minute.
- To designate urban nodes?Geolocalization optionsPrecise to district

Real-world QA triple play

Q：How to solve the problem of self-built agents always being blocked by the target website?
A: That's what using ipipgo is all about! They have a mix of residential IPs and server room IPs scheduled, blocking one for a second and switching to the next.

Q: Does the Python proxy support HTTPS?
A: You need to realize SSL handshake by yourself, and it is recommended to use their API directly to access it, which saves trouble and also comes with automatic certificate processing.

Q: How do I test if the proxy is working?
A: Add a print to the code to output the request logs, or just use the ipipgo suppliedOnline testing toolsThe IP attribution can be checked at a glance.

In the end, self-built proxies are good for practicing and learning, but if you really want to engage in business, you still have to be a professional. ipipgo's free trial package for new users contains three types of IPs, and after the test, you will know where the gap is. The next time you encounter anti-climbing mechanism, remember that a good proxy is the hard truth.