When it comes to web scraping, you’ll soon realize proxy management is a critical component.
Whenever you scrape the web at any reasonable scale, proxy servers are a necessity. The troubleshooting proxies cheap and management of proxy issues generally take a lot longer than building and maintaining the spiders themselves.
Here, we will explain how to choose the cheapest proxy for scraping the web and how to use them effectively.
Why Is It Necessary to Use Proxies When Scraping the Web?
Proxy servers allow you to route requests through their servers and use their IP address in the process. You can scrape the web anonymously by using a proxy when making requests to websites, since the websites no longer see your IP address, but the IP address of the proxy.
You should use a 3rd party proxy and set your company name as the user agent when scraping a website so the owner can contact you if the scraping overburdens their servers or if they want you to stop scraping data displayed on their site.
Proxy servers are important for data web scraping for several reasons:
- You can crawl a website more reliably with a proxy (especially a pool of proxies – more on this later). This reduces the chances of your spider being banned.
- A proxy allows you to request content from a specific geographical area or device (mobile IP addresses for example), allowing you to see the specific content the website displays for that particular location or device. This is extremely useful for scraping product data from online retailers.
- Proxy pools allow you to make more requests to a website without being banned.
- You can circumvent IP bans by using a proxy. Many websites block AWS requests because malicious actors have been known to overload websites with requests using AWS servers.
- You can run unlimited concurrent sessions to the same or different websites using a proxy.
Why Use a Proxy Pool?
If you only scrape a website using one proxy, just like scraping a website using our own IP address, you will reduce your crawling reliability, geotargeting options and the number of concurrent requests you can make.
You need to build a proxy pool to route your requests through. By using a large number of proxies, you can spread traffic.Several factors determine the size of your proxy pool:
- You will be making an average of one request per hour.
- A larger proxy pool is required for large websites with sophisticated anti-bot countermeasures.
- Whether you are using datacenter, residential, or mobile IP addresses as proxies.
- What is the quality of the IPs that you are using as proxies? Are they public, shared, or private dedicated proxies? Do they have datacenter, residential, or mobile IP addresses? The IPs used in data centers are usually lower quality than those used by residential and mobile customers, but they are often more stable due to the nature of the network.
- Proxy rotation, throttling, session management, etc. – the sophistication of your proxy management system.
Our next section will discuss the different types of IP addresses you can use as proxies.
Proxy Pool – How to Manage It:
Scraping at any reasonable scale will not be sustainable long term if you just purchase proxies and route your requests through them. It is inevitable that your proxies will get banned and no longer return quality data.
The following are some of the challenges you will face when managing your proxy pool:
- Ban Detection – Your proxy solution needs to be able to detect numerous types of bans in order to diagnose and resolve the underlying problem – e.g., captchas, redirects, blocks, ghosting, etc.
- Error Retry – Your proxies should be able to retry any errors, bans, timeouts, etc. with different proxies if they encounter any errors, bans, timeouts, etc.
- User-Agents – Maintaining user agents is vital to a healthy crawl.
- Control Proxies – Some scraping projects require you to keep a session with the same proxy, so you’ll need to adjust your proxy pool so that it allows for this.
- Add Delays:You can add delays and use throttling to disguise the fact that you are scraping.
- Geographical Targeting:If you need to control which proxies appear on certain websites based on geography, you can set up your pool so that only some proxies appear on those sites.