How To Build A Web Scraper

Web scraping is a necessary method of gathering and extracting data from websites, local servers, or the internet. Businesses widely use it across many different industries to monitor prices, competitors, find the best offers, and so on. Ever since it was first introduced, web scraping kept evolving, and today, it’s a very powerful tool that can make or break a company or business operation.

Most users have two options when starting their web scraping projects. They can create their own in-house web scrapers or use third-party tools designed for the same use. But which method is better, and what are their downsides? Stick with us, and we’ll give you all the information you need to make the best choice – from the concept of web scraping to the Python requests library.

Basics of Scraping

As we’ve already mentioned, web scraping is a process of finding specific information on a website, page, or local machine and extracting it in a readable format. Let’s say that you want to find some specific information on a website. Simply tell the web scraper what you’re looking for, and it will extract all relevant information, allowing you to get a better overview of all details you need.

web scraper

Once you tell a web scraper where to look and what information to look for, it will scan all webpages, download the specific information to your device, and organize it in a spreadsheet allowing you to gain valuable insights. The extracted information can then be used for further analysis. Web scrapers can also gather images, videos, help you generate leads, find customer reviews, and so on.

How Scraping Works

Web scraping is generally a very simple process because of advanced tools that use bots to scan and extract all information without wasting time and in an automated manner. The extraction is done using the website’s HTML code which is then decoded and placed in a readable spreadsheet file. After you run the tool and specify the website or page you want to scrape for information, the scraper sends a request to the server and reads all information. It identifies the specific elements based on keywords you provide and puts them in a spreadsheet.

Within the real estate sector, industry players are adopting scraping tools to outpace competition and boost lead generation. By specifically scraping Zillow, the biggest real estate marketplace in the United States, utilizing advanced tools and services becomes essential for swiftly and efficiently extracting and analyzing valuable property data. This strategic use of scraping not only helps professionals stay ahead of market trends but also facilitates more effective connections with potential clients, ultimately enhancing their competitive position in the real estate landscape.

The process is pretty much the same for all scraping projects. Web scrapers can process huge amounts of data, as well as smaller local databases. However, many websites and businesses use a multitude of protective systems to prevent web scrapers from finding information. That’s why most scraping projects require the use of proxies that effectively prevent sites from blocking IP addresses.

What is a Web Scraper?

Web scrapers are special tools designed for finding and extracting data from servers and websites. There is a wide range of different web scraping tools you can try, but all of them can be divided into three primary categories:

  • In-house scrapers
  • Third-party scrapers
  • Browser extensions

These three primary types can also be divided by the way they operate into cloud-based, web-based, and local web scrapers. Third-party web scrapers are the most popular of all because they are very easy to set up without any previous knowledge. It’s important to know that all web scrapers have limitations, so you have to set them up correctly to get the best possible results.

In-house vs Third-party Scraper 

Both in-house and third-party web scrapers are excellent tools for gathering and extracting data. They both have a few pros and cons you have to know about before you can find the best choice for your needs. Here’s a quick overview of things you can expect from both options.

In-house web scraping

In-house web scraping solutions are usually made by large companies that employ a team of full-stack developers. Custom web scrapers offer the best data quality because you can set everything up in detail. It’s also faster because there’s no lag between you and the server. They are the best option if you need answers quickly, with minimum downtime. 

The downsides are the cost, which is much higher than when using third-party web scrapers. The maintenance is also costly, can lead to legal consequences if not set up correctly, and your team can get lost in the process after some time.

Third-party web scrapers

Third-party web scrapers are a better option if you don’t have a lot of scraping projects and if you run a small local business. Since it uses established tools operated by experts who know everything about web scraping, you won’t have to worry a thing about data collection and extractions. You will give up some control, but you’ll get a flexible platform ideal for any type of scraping in return.

The downsides are that you won’t be able to affect the scraping process as much as with an internal web scaper. Also, keep in mind that some third-party web scraping ads promise more than they can provide, leaving you with poor data quality you can’t really use to your benefit.

Building a Web Scraper

If you decide that you want to build your own web scraper, you will need excellent coding knowledge in Python. If your company already employs a full-stack team of developers, you can create a web scraper for a reasonable price. Your programmers should use Puppeteer, which works as an unofficial port for Python. It works similarly to the original software but with some important differences. 

Creating an in-house web scraper also takes some time, and you probably won’t be able to generate ideal results the first few times. Take a look at our puppeteer tutorial to start building your custom web scraper today.

If you’re interested in building a web scraper and want to dig deeper, read this in-depth guide on the Python requests library.

Conclusion

As you can see, both in-house and third-party web scrapers come with specific pros and cons, so you have to sit down and see which one works best for you. If you have the workforce and the time to invest in an in-house solution, it will give you the best results. However, if you use a web scraper only for some specific data, using a third-party solution is easier and more convenient.