Specify the URLs of the websites and pages you want to scrape
Posted: Tue Dec 17, 2024 7:02 am
Scrapers do the dirty work of quickly extracting relevant information from websites. Since websites are structured in HTML, scrapers use regular expressions (regex), XPath, CSS selectors, and other locators to quickly find and extract certain content. For example, you can give your web scraper a regular expression that specifies a brand name or a keyword.
If this sounds a little overwhelming, don't worry. Most web scraping tools include built-in crawlers and scrapers, making it easy to get through even the most complicated jobs.
Basic Web Scraping Process
At its most basic level, web scraping boils down to a few simple steps:
Make an HTML request to the URLs (i.e., “visit” the pages)
Use locators like regular expressions to extract the desired information from the HTML
Save the data in a structured format (such as CSV or JSON)
As we’ll see in the next section, a wide range of web scraping tools can be used to perform these steps automatically.
However, it’s not always that simple — especially when armenia whatsapp number data you’re doing web scraping on a large scale. One of the biggest challenges in web scraping is keeping your scraper up to date as websites change designs or adopt anti-scraping measures (not everything can be evergreen). While this isn’t too difficult if you’re only scraping a few websites at a time, scraping more can quickly become a hassle.
To minimize extra work, it's important to understand how websites try to block scrapers — something we'll learn in the next section.
Web Scraping Tools
Many web scraping features are available in the form of web scraping tools. While there are many tools available, they vary widely in quality, price, and (unfortunately) ethics.
In any case, a good web scraper will be able to reliably extract the data you need without running into too many anti-scraping measures. Here are some key features to look for.
Accurate Locators: Web scrapers use locators like regular expressions and CSS selectors to extract specific data. The tool you choose should allow you several options to specify what you're looking for.
Data Quality: Most data on the web is unstructured, even if it's presented clearly to the human eye. Working with unstructured data is not only messy, it rarely delivers good results. Make sure to look for scraping tools that clean and sort raw data before delivery.
Data delivery: Depending on your existing tools or workflows, you'll likely need scraped data in a specific format, such as JSON, XML, or CSV. Rather than converting raw data yourself, look for tools with data delivery options in the formats you need.
Handling anti-scraping: Web scraping is only as effective as its ability to bypass blocks. While you may need to employ additional tools, such as proxies and VPNs, to unblock websites, many web scraping tools accomplish this by making minor modifications to their crawlers.
Transparent pricing: While some web scraping tools are free to use, more robust options come at a price. Pay close attention to the pricing scheme, especially if you intend to scale and scrape many sites.
Customer support: While using a pre-built tool is very convenient, you won't always be able to troubleshoot issues yourself. Therefore, make sure your provider also offers reliable customer support and troubleshooting resources.
Popular web scraping tools include Octoparse, Import.io, and Parsehub.
If this sounds a little overwhelming, don't worry. Most web scraping tools include built-in crawlers and scrapers, making it easy to get through even the most complicated jobs.
Basic Web Scraping Process
At its most basic level, web scraping boils down to a few simple steps:
Make an HTML request to the URLs (i.e., “visit” the pages)
Use locators like regular expressions to extract the desired information from the HTML
Save the data in a structured format (such as CSV or JSON)
As we’ll see in the next section, a wide range of web scraping tools can be used to perform these steps automatically.
However, it’s not always that simple — especially when armenia whatsapp number data you’re doing web scraping on a large scale. One of the biggest challenges in web scraping is keeping your scraper up to date as websites change designs or adopt anti-scraping measures (not everything can be evergreen). While this isn’t too difficult if you’re only scraping a few websites at a time, scraping more can quickly become a hassle.
To minimize extra work, it's important to understand how websites try to block scrapers — something we'll learn in the next section.
Web Scraping Tools
Many web scraping features are available in the form of web scraping tools. While there are many tools available, they vary widely in quality, price, and (unfortunately) ethics.
In any case, a good web scraper will be able to reliably extract the data you need without running into too many anti-scraping measures. Here are some key features to look for.
Accurate Locators: Web scrapers use locators like regular expressions and CSS selectors to extract specific data. The tool you choose should allow you several options to specify what you're looking for.
Data Quality: Most data on the web is unstructured, even if it's presented clearly to the human eye. Working with unstructured data is not only messy, it rarely delivers good results. Make sure to look for scraping tools that clean and sort raw data before delivery.
Data delivery: Depending on your existing tools or workflows, you'll likely need scraped data in a specific format, such as JSON, XML, or CSV. Rather than converting raw data yourself, look for tools with data delivery options in the formats you need.
Handling anti-scraping: Web scraping is only as effective as its ability to bypass blocks. While you may need to employ additional tools, such as proxies and VPNs, to unblock websites, many web scraping tools accomplish this by making minor modifications to their crawlers.
Transparent pricing: While some web scraping tools are free to use, more robust options come at a price. Pay close attention to the pricing scheme, especially if you intend to scale and scrape many sites.
Customer support: While using a pre-built tool is very convenient, you won't always be able to troubleshoot issues yourself. Therefore, make sure your provider also offers reliable customer support and troubleshooting resources.
Popular web scraping tools include Octoparse, Import.io, and Parsehub.