Web scraping is all about collecting information in a structured manner – and doing it automatically. Rather than painstakingly piecing information together, computer servers and smart software/scripts can do the heavy lifting by accessing all available sources to perform information collection.
The technology is applied to collecting information on competitors, checking prices on different websites, scanning for relevant news across a multitude of sources, finding good sales lead prospects, and researching a market efficiently. It’s also used for less salubrious reasons too.
Read on for a guide to web scraping. We’ll also discuss how a high quality USA proxy can help you resolve potential issues.
Web Scraping: Doing It by Hand
It is possible to do it by hand. You have likely already done this when checking a competitor and copying some information down from their site.
For instance, this might have been performed to collect the top 10 bestsellers on five competitors to see which products you needed to stock for a new dropshipping business.
Bloggers may take their cue from other websites and what they’re writing about – especially if their content leans more towards the latest news and less about op-ed or editorial pieces.
Manual scraping still works, but it’s hugely time-consuming. Also, as the amount of information and/or the number of different sources grows, it becomes far less practical as a strategy.
Web Scraping: Getting Up to Speed
Automated web scraping using tools is done in two stages:
Firstly, a web crawler is utilized to browse the relevant places on the internet. This spider tool crawls through pages following links and looks around for the right information. Commonly, a scraping crawler will take a target website URL, explore that site, and then move onto the next site on the list.
Secondly, a web scraper is used to retrieve the desired information and extract it from the web page. The amount and complexity of the information retrieved depend on the scraper. It might be all of the page’s content or only specific parts of the information or the code.
Does Automated Scraping Cause Any Technological Issues?
In terms of how often a website is visited, the number of pages loaded and what information is scraped, this may create a server load issue for a small website. Badly coded web scrapers can artificially cause too much of a load on a server when they repeatedly return after previous unsuccessful collection visits. Limitations must be placed to avoid becoming a problem for a website, but that doesn’t always happen.
Avoiding Blocking Issues
Since some spiders are more invasive than others, crawl for too long, or return too frequently, some sites will put blocks in place. This is often by isolating the offenders through their IP address and preventing access to the site in the future.
Using a US proxy service can help you resolve blocking issues. The idea is that a proxy replaces the regular fixed IP address with a completely different one. Proxy services rotate through IP addresses every so often or use a different IP address with each new connection to prevent your web scraping activities from being blocked by the site.
How is Web Scraping Usually Performed?
Once you have a good proxy service in place to avoid getting blocked early on in the web scraping process, then you’re ready to proceed.
The basic process of web scraping when you’re doing it yourself is as follows:
Find a Target – Pick a website or websites that you’ll gather information from.
Maintain a List – Build up a list of URLs and separate the ones that have already been scraped from those that have not.
Web Scaping – Request the HTML from the web page(s) from the list of URLs
Finding What Is Needed – Scan the HTML using locators to find the necessary information.
Saving the Work – Take the scraped data and save it for future reference in either a CSV or JSON file.
What Problems Are Experienced with Web Scraping at Scale?
A web scraper is based on creating a coded solution that can successfully visit, capture, and record information as needed. A scraper can be correctly put together and still run into difficulties for several possible reasons.
- Website Changes Layout
A website can change layout after a web scraper has been set up to repeatedly collect information from it. This can cause a spider to fail in its mission to scrape the content completely. This will result in you needing to recode the scraper to solve the issue.
- Poorly Coded HTML without Locators
HTML uses tags or locators to clarify the information provided that is subsequently displayed by web browsers. When these are poorly described, it can be difficult for a web scraper to know what it’s looking at. Because scrapers either don’t have built-in AI or it’s extremely limited, they cannot easily interpret the information to locate what they’re after in the same way that a human can. That is unless they’re programmed to be able to do so.
- Honeypot traps set by developers
Websites can be programmed to detect scraping bots and to send them down blind alleys or otherwise deter their actions. This is known as a honeypot strategy and is increasingly seen due to the higher percentage of bots being used online now.
- Slow loading speed
Too many bots visiting a site can cause it to become slower than it otherwise would. When a site is using cheap shared hosting, it can begin to significantly impact the speed. For scrapers, this makes the wholesale collection of information across many pages a slow task. Often, many page requests will timeout. It may be necessary to limit retrievals to 2-3 pages per visit to avoid issues here – this is slow going when the site is substantial in size and the intention is to scrape all of it.
- Blocking because of scraping activities
Simply put, the way to get around this is to use a private proxy. This rotates through many IP addresses to avoid a single one getting identified and blocked at the server level.
Web scraping as either an information-gathering resource or to get a competitive edge should be approached with caution. There are right and wrong ways to go about it, and it pays to do it properly to avoid unwanted or unexpected issues