Online datasets: online dataset resources

A. Crawling data is always blocked? You may lack a good helper

Old drivers who do data collection understand that the biggest headache is when the target website suddenly gives you aIP blockingThis is the value of proxy IP. It's like driving a truck to transport goods, just half loaded truck was stopped outside the door - this time you need to find a reliable "middleman", this is the value of the proxy IP.

Take a real scenario: Xiao Zhang wanted to catch the price of goods of an e-commerce platform, wrote a crawler script. The first three days ran quite smoothly, the fourth day suddenly403 errorSwiping. This is typical of IPs being recognized as crawlers and going straight to the blacklist. If he had used a dynamic proxy IP pool earlier, this problem would never have occurred.

import requests
from itertools import cycle

 Example of a proxy node for ipipgo (replace with real information for real use)
proxy_list = [
    "http://username:password@proxy.ipipgo.com:8000",
    "http://username:password@proxy.ipipgo.com:8001"
]
proxy_pool = cycle(proxy_list)

for page in range(1, 10): proxy = next(proxy_pool)
    proxy = next(proxy_pool)
    try: response = requests.get()
        response = requests.get(
            "https://目标网站.com/products?page="+str(page), proxies={"http": proxy, "https": proxy}
            proxies={"http": proxy, "https": proxy}
        )
        print(f "Page {page} captured successfully")
    except Exception as e.
        print(f "Automatic IP switching on exception: {str(e)}")

Second, what are the hard indicators to look at when choosing a proxy IP?

There are a plethora of proxy service providers on the market, but the really good ones have to look at these three things:

1. (med.) recovery rateDon't get disconnected while you're using it. ipipgo's nodes have a survival rate of 99.21 TP3T or more.
2. responsiveness: Measured latency below 800ms is considered passable
3. IP purityMany cheap proxies use "dirty IPs" that have been flagged by major platforms.

Here to teach you a testing technique: visit https://httpbin.org/ip 20 times in a row, if the returned IP address changes every time, it means that the quality of the proxy pool is good. When testing with ipipgo, I found that their IP replacement success rate reached 100%, which is really amazing.

Third, hand in hand to teach you to take agents in the program

In the case of the Python crawler, for example, accessing ipipgo takes only three steps:

1. Get it after registering on the official websiteAPI address
2. Set the logic of automatic IP change in the code
3. Add a fail-over mechanism and you're all set.

Focus on the pitfalls that many will step into:
- Don't write the proxy account password directly in the code, it is recommended to put it in an environment variable.
- It is better to bind a fixed IP address for each session to avoid switching in the middle of the session, which may cause the login state to be invalid.
- Set reasonable request intervals, don't think you can do whatever you want with proxies!

iv. guide to demining common problems

Q: What should I do if I use a proxy IP and still get blocked?
A: Check the request header with browser fingerprint, don't use the default Python-requests header. It is recommended to use fake_useragent library to generate randomly.

Q: What if I need to collect data from overseas websites?
A: ipipgo has specialized city-level location services, such as specifying residential IPs in Los Angeles, U.S.A., and pro-testing catching Amazon product information is as steady as an old dog.

Q: What is the difference between a free agent and a paid agent?
A: A real case: colleagues trying to save trouble with free proxy crawl data, the results of three days later received a warning from the cloud server provider - it turned out that those IPs have long been used to send spam, the server room to the entire IP segment have been blacked out.

V. Why professionalism should be left to the professionals

It's not impossible to build your own proxy server, but the maintenance costs are prohibitive. To worry about IP cleaning, channel procurement, node monitoring ... any which can let the development of the hair off. With ipipgo such service providers, the equivalent of hiring a 24-hour standby operation and maintenance team, measured than self-built costs lower than 60% or more.

They've recently put on a newpay per volumemode, especially friendly to small and medium-sized projects. For example, to collect 1 million pieces of data, the cost of the agent can be controlled within 30 dollars, which is much cheaper than recruiting an operation and maintenance.

In the end, the proxy IP is like the data collection "invisible war clothes", choose the right equipment to get twice the result with half the effort. Next time you encounter anti-climbing mechanism do not rush to change the code, change your mind to try ipipgo's services, there may be surprises.