Blog
Software Guides, Tutorials and News
The Complete Guide to Proxies for Web Scraping
The Internet has brought lots of comfort in our lives, especially in terms of searching for information. Just click your keyboard and voila, you can know or search anything through the internet. You can even get data from a website and transfer it either through the script or software - this action is called web scraping. There is a web scraping software that can help in accessing the World Wide Web using a Hypertext Transfer Protocol or through the web browser, and the data being copied can be saved in a central local database or spreadsheet that aims to be studied later on.
What are the Uses of Web scraping?
Web scraping is not only used for transferring data, but it is also used in the following:
- Contact scraping
- Web indexing
- Web mining
- Data mining
- Monitoring online prices
- Online price comparison
- Product review monitor
- Web mashup
- Web data integration
- Website change detection
- Tracking online presence
- Research
- Weather data monitoring and many more.
This web scraping technique was first created after the World Wide Web in 1989 was born. Then in December 1993, the crawler-based web search engine was launched through Jumpstation. In 2000, Web API or Application Programming Interface came to make the job of the programmers easier - since they can download available data to the public.
What are the Techniques in Web Scraping?
- Copy – and - Paste technique – this is the simplest form of web scraping wherein you manually copy and paste the data from a webpage and transfer it to your worksheet.
- Text pattern matching – it is matching the facilities of programming languages like Perl or Python to extract data.
- HTTP programming – HTTP requests are posted to some web server using socket programming is used to retrieve some information from static and dynamic web pages.
- HTML parsing – this is done by parsing some HTML pages, retrieve and transform the page content using semi-structured data query languages like XQuery and HTQL.
- DOM Parsing – Xpath is used to parse some DOM tree to get the data.
- Vertical Aggregation – this is through creating bots to harvest information from complicated content.
- Semantic annotation recognizing – metadata or semantic markups and annotations are used to locate snippets of data.
- Computer vision webpage analysis – webpage information is being scraped by interpreting pages visually through machine learning and computer vision.
What is a proxy, and Why is it Important to Use Proxy in Web Scraping?
To do web scraping, a proxy is needed, so what is a proxy? Proxy is known as an intermediary server or the 3rd party server that will help you make your requests to some websites without the fear of knowing your location or your IP address.
However, using a proxy is important in doing web scraping, and here are the reasons why:
- The proxies will help your spider to avoid being banned or blocked from the website that you are web scraping.
- The proxy will help you see a specific content of the website from a given location or device. This is a good help for online retailers.
- The proxy can help you make more requests to a certain website without being banned.
- The proxy can help you get saved from IP bans that some websites have imposed.
- The proxy can help you make unlimited requests to the same or different websites.
What are the factors in choosing the size of the proxy pool?
In doing web scraping, one proxy is not enough because it will reduce the number of your concurrent requests, crawling reliability, and geotargeting options. That is why proxy pools are needed to split the amount of traffic to the large numbers of proxies. However, to know the size of the proxy pool to use, consider first the following factor.
- 1. Consider the number of requests you are going to make every hour.
- 2. Consider targeted websites.
- 3. Consider the types of IPs to use for your proxies. Here are the three types of IPs.
- Datacenter IPs – these IPs of servers in datacenters
- Residential IPs – this is private IPs of residences, and they are using residential networks.
- Mobile IPs – these are IPs of private mobile devices.
- 4. Consider the qualities of the proxies to be used – is it a Public proxy? Is it a shared proxy? Or is it a private proxy?
- 5. Consider the sophistication of your proxy management system – is it proxy rotation, or throttling, or session management?
All of these five factors are needed to be considered to have a successful use of proxy in web scraping.
What will be the challenges in managing your pool?
It is not easy to manage a proxy pool in web scraping, but it is worth a try. It is not easy because you will encounter lots of challenges while managing it, and the following are the challenges that you need to be aware of.
- Identifying Bans
- Retry Errors
- User-Agents
- Control Proxies
- Add delays
- Geographical Targeting
How to choose the Best Proxy Solution?
- 1. Know your budget – how much you have budgeted for your proxy pool? If you have a lesser budget, it is wiser if you will manage your own proxy pool, but if you have a bigger budget, then you can look for someone to help you with it.
- 2. Know your priority – if in your mind your priority is to have your own pool, then manage it, but if not, try to get a proxy rotator.
- 3. Know your technical skills and level – your technical skills are important. You need to know at least a basic one so that it is easy for you to manage and do troubleshooting in your proxy if needed.
What legal considerations do you need to think about while using a proxy?
Using proxy while web scraping is legal, you need to consider some things to maintain legality in what you are doing. One thing you need to consider in doing the web scraping is to be polite and respectful to the websites that you are scraping. If the websites inform you that you are burdening their site, then limit what you are doing. Always learn to follow the guidelines to avoid future legal problems in the future.