A lot of data gathering is being done through web scraping, whether it be for business, research or development. Web scraping allows one to extract data from websites and also perform various other tasks. And one of the problems that one might face during web scraping is getting blocked by websites. This is where proxies come into play.
In this blog, we'll dive into what proxies are, why they are essential for web scraping, and how to use them effectively.
Why does websites block scraping attempts?
Web scraping requires a lot of requests made to a server from an IP address. The server may detect this and block the IP address to stop further scraping. In most cases, it happens because the scrapers violate the website's terms of service (ToS) or generate so much traffic that they abuse the website's resources and prevent normal functioning. And so to protect itself, the website bans the IP from accessing its resources either temporarily or permanently.
Is this blocking the only reason why proxies are used?
Avoiding detection: Many websites rely on anti-bot systems to protect their data, primarily by monitoring IP addresses. The systems block suspicious IPs, some of them even permanently. By using proxies, you can rotate IP addresses and avoid getting blocked.
Geo-restricted Content: Some websites restrict content based on geographic locations. By using proxies located in different regions, you can access geo-restricted content.
Anonymity: Proxies can hide your actual IP address, making it difficult for websites to trace your scraping activities back to you.
Improved Performance: Using multiple proxies can distribute the load of requests, which can improve the efficiency and speed of your scraping activities.
What is a Proxy?
Before we look into what a proxy is, let’s first understand what an IP address is.
An IP address is a numerical address assigned to every device that connects to a network like the internet, giving each device a unique identity. Most IP addresses look like this:
“192.158.1.38”
A proxy is a 3rd party server that enables you to route your request through their servers and use their IP address in the process. This IP address used by the proxy server is known as a proxy IP address.
A proxy server acts as an intermediary between your computer and the internet. When you make a request to a website through a proxy, the request is first sent to the proxy server. The proxy then forwards the request to the destination server of the target website on your behalf. When the website responds, the proxy server forwards the response back to you. This effectively results in the website only seeing these proxy IP addresses and not your actual IP address.
Different types of Proxies
Residential Proxies: These are IP addresses assigned to real residential devices by Internet Service Providers (ISPs). These ISP proxies are less likely to be detected and blocked by websites. This means that they help retain anonymity, prevent bans, and access geo-restricted sites. Since they appear as if they come from a real user, they are highly effective for web scraping and similar activities. However, they also come with the downside of high costs.
Datacenter Proxies: These are IP addresses provided by data centers. They are faster and cheaper than residential proxies but are more likely to be detected and blocked.
Mobile Proxies: These are IPs of private mobile devices and work similarly to Residential IP Proxies. And similar to residential proxies, they have great anonymity and prevent bans but comes with the downside of high costs.
Public Proxies: These are free proxies available to the public. But they are often unreliable and insecure, making them less suitable for web scraping. Public proxies are often obtained through proxy scraping, which involves running a scraper to collect these free proxies from various sources.
Dedicated Proxies: These proxies are exclusive to a single user, meaning they are not shared with others. They provide a high level of anonymity and reliability, as they reduce the risk of being blacklisted due to other users' activities. Dedicated proxies are particularly useful for tasks that require consistent performance and higher security.
ISP Proxies: ISP proxies combine the benefits of residential and datacenter proxies. They are provided by ISPs but hosted in data centers, making them faster and more reliable than residential proxies while still appearing as regular residential IPs to websites. Typically less expensive than residential proxies but more expensive than standard datacenter proxies.
Anonymous Proxies: These proxies hide the user's IP address and other identifying information, making the user's internet activity untraceable. They ensure that websites cannot trace the request back to the user. These are used by users that want to have full anonymity while accessing the internet.
Best Practices in Using Proxies
To maximize their effectiveness and ensure a seamless scraping process, it's crucial to follow best practices. By adhering to these best practices, you can enhance the reliability and efficiency of your web scraping operations, minimize the risk of getting blocked, and ensure compliance with website policies. In this section, we will delve into the concept of proxy pools, strategies for managing them, and how to implement proxy rotation, particularly using the Playwright library in Python.
The concept of Proxy Pool
Rather than using a single proxy for scraping and thereby limiting ourselves, a pool of proxies through which you can route your requests is created, splitting the amount of traffic over a large number of proxies.
If you don’t properly configure your pool of proxies for your specific web scraping project you can often find that your proxies are being blocked and you’re no longer able to access the target website.
The proxy pool will depend on a number of factors:
number of requests made per hour.
target website - websites with more sophisticated anti-bot measures will require larger proxy pool.
proxy types used - datacenter, residential or mobile.
Managing your proxy pool
Managing a proxy pool effectively is crucial for maintaining the efficiency and reliability of your web scraping operations. Here are some key strategies and considerations to ensure your proxy pool is well-managed:
Detecting Bans- Your proxy management system should be capable of identifying various types of blocking mechanisms employed by websites such as captchas, redirects, blocks, ghosting, etc.
Retrying Requests- If a request encounters a connection problem, block, or captcha, the system should automatically retry the request using a different proxy server.
Maintaining Session Consistency- For websites requiring authentication, it is essential to maintain session consistency with the same IP address. If the proxy server changes, the authentication might fail, necessitating re-authentication.
Adding Delays- To avoid detection and mimic human behavior, introduce randomized delays between requests.
Geographical Considerations- Some websites provide content based on the user's geographical location. Ensure your proxy pool includes IP addresses from the required geolocations to access geographically restricted content.
Concept of Proxy Rotation
A proxy rotator is a system designed to change proxies for each request made by a scraper or crawler. It’s referred to as a rotator because, once the last proxy in the pool has been used, it cycles back to the first proxy. This is where our proxy pool comes into play. The proxies present in the pool are rotated according to our needs.
Rotating proxies are ideal for users who need to do a lot of high-volume, continuous web scraping. There are also services providing rotating proxy capabilities. However, you have to be careful when choosing these rotating proxy services. Some of them contain public or shared proxies that could expose your data.
Implement proxy rotation in Playwright
As explained earlier, to avoid detection, it’s essential to rotate proxies periodically. Here’s an example of how to do it in Python using the Playwright library:
In the provided code, we see that the proxy pool contains two proxies. However, these proxies are of the public type and can therefore be unreliable, potentially breaking at any time. To enhance the reliability of your scraping tasks, consider replacing these public proxies with private or residential proxies obtained from third-party services.
This also brings us to the next topic of our blog.
Best Practices in Buying Proxies
Choosing the right proxy provider for web scraping depends on your specific needs and goals. Here are some critical factors to consider before making your decision:
Budget: Determine how much you are willing to spend. Providers offer various pricing plans, so choose one based on your budget.
Data Needs: Evaluate the volume of data you plan to scrape and the number of concurrent requests you need to run. Providers offer different capacities, so ensure your chosen provider can handle your requirements.
Analytics Panel: Consider if you need a built-in analytics panel. An analytics panel can provide valuable insights into your scraping activities, helping you optimize performance and troubleshoot issues.
Automation and Maintenance: Assess how much automation the tool provides and how much time you will need to spend on maintenance and manual tasks.
API Availability: Check if the provider offers an API. APIs allow you to easily integrate proxies into your existing systems, and thus allow you to easily scale your application.
Once you've shortlisted a few candidates, take advantage of the free trials many proxy providers offer. Test the proxies on a real-life use case to see if they meet your needs and expectations. Look for a proxy solution that aligns with your scraping needs. The right proxy solution should provide reliable performance, and should satisfy the above factors.
Conclusion
Using proxies for web scraping is a powerful technique to avoid detection, maintain anonymity, and access restricted content. By choosing the right type of proxy, configuring your scraping tool, and following best practices, you can scrape websites efficiently and responsibly. Remember to respect website policies and handle proxy failures gracefully to ensure your scraping activities are sustainable and ethical.
Connect with Datahut for top-notch web scraping services that bring you the information you need, hassle-free.