FAQ|15 Most Frequently Asked Questions about Web ScrapingWednesday, March 9, 2022
If you want to obtain fresh web data and turn it into a valuable asset for your business, web scraping is the best way to make scalable data requests more productive.
Like the majority of us who lack programming skill sets, you probably have tons of doubts about scraping: how the process works, what the legal consequences of data abuse are, how I can scrape the data without coding, etc.
Web scraping is not as simple as black and white, especially in today’s complex network environment. Let me walk you through the nuts and bolts about web scraping.
FAQ| Web Scraping Problems
Web Scraping has a lot of nicknames, like data scraping, web data extraction. The idea is, it is the method used to pull the data from the websites into usable formats or local databases for later analysis or retrieval.
Simply put, the process is just the same as how you “copy and paste” stuff into a spreadsheet. Instead of doing it manually, we use a robot. You can think of it as a computationally reproducible data-collection workflow.
Many people have false impressions about web scraping. That is because it has been widely adopted to retrieve sensitive data regardless of terms of service. Web scraping itself is not illegal as it is just a tool for collecting data more easily. According to a report, 2% of online revenues can be lost due to the misuse of content through web scraping. However, there are still no clear laws regulating web scraping.
That is not saying we can fetch any data regardless. All of us need to follow the guidelines and be respectful. According to General Data Protection Regulation, web scraping is permissible to scrape publicly available information. Octoparse is GDPR compliance in which we only scrape publicly available information. And we do it in a manner without burdening the servers of a web host.
In terms of legal consequences, it matters how much data you’re getting and how you use the data. It is probably against the terms of service scrape listings, but for all practical purposes, if you just use it yourself without infringement, no one is going to bother you. Here is more information about how you should process the data. https://www.octoparse.com/octopus-data-inc-data-processing-agreement If it is a big concern to you, I suggest: asking for their approval to aggregate information; consulting an attorney who knows about the underlying legal obligation towards aggregated data.
Read more: Is web crawling legal?
3. Which’s the best web scraping tool?
The first step in finding the most appropriate extraction software for your organization’s needs is figuring out the options you have. By Googling, you will discover a lot of related applications. Pay extra attention to those suggested by people working in organizations similar to yours. Some tools are more robust with advanced features that require a steep learning curve.
Some are much easier to get hands-on but lack comprehensive functions to deal with dynamic websites. The free trial allows you to get hands-on experience with these tools and evaluate not only their functionalities, but also the ease of use, and the quality of support provided.
Read more: Best Data Scraping Tools for 2020
4. Can I scrape LinkedIn or Facebook?
Unfortunately, both websites block automated web crawling via their robots.txt. LinkedIn’s legal disputes with companies that have scraped data off them have been a hot topic. But it is not saying you can’t scrape the information. It is possible to extract very limited information from public-facing accounts.
5. What is web scraping used for?
Web scraping is aimed at collecting data so it can be applied in any industry that needs the data. Every industry has its unique use case. Combining with powerful tools like PowerBI, Tableau, SQL Server, companies can easily transform disparate datasets into one centralized place. Even better, visualizing these data through graphical representation can make your life easier.
Here are some examples in the Retail industry: why web scraping may benefit your business
6. Can I extract data from the entire web?
Google Search does but certainly not web scraping. They share similar features but are different. Google will index the entire web and discover relevant information. That’s how Google can tell which website contains the information you’re looking for. Whereas web scraping can only retrieve raw data from one or multiple sources. In other words, one web scraper can’t interact with multiple websites. This means that web scraping takes a more focused approach which can extract specific data points from one website.
For example, a typical scraping project seeks to extract product detail information like pricing, descriptions, title, inventories from Amazon.
7. Is web scraping data mining?
Web scraping and data mining are two different concepts. Web scraping is to collect raw data, but data mining is the process of discovering patterns in large data sets.
Read More: Data Mining (Wiki)
8. How to avoid being blocked when scraping a website?
It’s not uncommon for websites to implement blocking mechanisms in case of any malicious scraping attacks. A large number of data requests will burden the internet server, and eventually, it will crash. None of us could benefit from this no-win situation. The best way to get away with being blocked is by preventing this from happening. Go conservative and be gentle. Try to slow down the scraping process just like a real human being browsing a website. For example, you can add a delay between two requests, use IP proxies, or apply different scraping patterns.
9. Can CAPTCHA be solved during web scraping?
CAPTCHA used to be a nightmare for web scraping, but now can be solved easily. Many web scraping tools have the feature of solving CAPTCHA automatically during the extraction process. And there are lots of CAPTCHA solvers that can be integrated with scraping systems.
10. Can I republish the content extracted via web crawling?
Republishing content needs to have consent from the owner. Though you can scrape text content from websites that allow bots, you still need to use this data in a way that does not infringe the copyrights of the publisher.
11. What is a robots.txt file?
Robots.txt is a text file that tells crawlers, bots, or spiders if a website could be or how it should be scrapped as specified by the website owner. It is critical to understand the robots.txt file to prevent being blocked while web scraping.
12. Can I scrape data behind a login page?
Yes, you can scrape data behind a login page easily if you have a functional account on the website. The scraping process after the login would be similar to that of a normal scraping.
Read More: Extract data behind a login
14. How do I extract the content from dynamic web pages?
A dynamic website would update data frequently. For example, you will see infinitive scrolling on Twitter. It serves as pagination. When you scroll to the bottom of the page, it will load more historical posts. To scrape from such a website is the same process as scraping other websites but you would let the scraper access the website at a certain frequency to get the updated data continuously.
15. Can a web scraping tool download files from a website directly?
Yes, there are many scraping tools that can download files on the website directly and save to Dropbox or other servers when scraping text information.
Artículo en español: Las 15 preguntas más frecuentes sobre Web Scraping (Q&A)
También puede leer artículos de web scraping en el Website Oficial
Author: Yina Huang (The Octoparse Team)
Edit: Ashley Weldon