12 Mistakes to Avoid When Scaling Web Scraping

Scaling web scraping alone is not easy. It requires careful planning and preparation to avoid common pitfalls. If you try to do everything yourself, it will take more time and be more difficult.

However, that does not mean you shouldn't attempt to scale web scraping on your own. On the contrary, web scraping allows you to avoid these pitfalls.

But how easy is it to avoid getting blocked while web scraping? Keep reading to learn about 10 mistakes to avoid when scaling web scraping.

What is Web Scraping?

Web scraping is the process of extracting information from websites using automated tools and software. It is often used in business intelligence (BI) and data science applications to collect data for analysis.

It is not limited to websites; it can be applied to various data sources. For example, web scraping may involve crawling the internet, reading web page content, or extracting structured data via APIs (application programming interfaces).

That is a brief definition of web scraping. Now let us look at 10 common mistakes to avoid when web scraping.

1. Not Saving Raw Data

A crucial step in data extraction is persistently preserving the original data. Raw data contains all the information in a file, including metadata and other details that are typically removed when processing files with file-processing tools. This additional information can be useful when trying to identify and understand patterns in the dataset, etc.

Another important step is to ensure these raw data are reliably stored so they are not lost or corrupted. It is also important to note that not all file-processing tools remove this information, so you should verify it before starting analysis.

2. Not Knowing the Ethical Implications of Scraping

Many companies are disapproving of scraping. They often send you a letter demanding that you stop using their data. You must keep this in mind as you scale your data collection activities.

If you are collecting data from sites that do not want you to collect their data, it may be better to collect data differently.

For example, suppose you are collecting data from sites that use CAPTCHA to block crawlers. In that case, it is better to use an optical character recognition (OCR) service to bypass CAPTCHA. This is one way to scale your data collection operations while avoiding legal issues.

3. Not Checking Whether the Site Has Its Own API

Before you start scraping, check whether the developer has their own API and choose the optimal method for obtaining the required data. This prevents doing more work than necessary.

Additionally, the needed data may be easily accessible. So first double-check whether reliable, well-formatted, and accessible information already exists.

4. Not Using a Consistent API for Storing and Retrieving Data

If you store data in multiple places, it increases the risk of data loss. Therefore, you should instead store data consistently across all storage options.

For example, suppose you store data in an SQL database, a NoSQL database, or an Excel spreadsheet. In that case, you must use a uniform data format for all storage. This simplifies access to and use of data across all storage locations.

5. Scraping Too Fast and Not Using Unpredictable Intervals

It is well known that the speed at which bots and humans browse sites differs. Bots scrape sites at high speed.

Random requests to a site are not suitable. As a result, sites crash due to request overload. To avoid this problem, have the bot take a programmatic pause between scraping actions. This way, the bot will appear to anti-scraping tools as a real human and will not harm the site.

First, make parallel requests to minimize the number of saved pages. Then, after a timeout of approximately 25–35 seconds, continue scraping.

Respect the robots.txt file. Disable automatic throttling mechanisms that would automatically adjust crawling speed based on the load on the spider and the site.

After several trial runs, configure the spider to an optimal crawling speed. Of course, conditions change over time, so periodically make adjustments.

6. Using Unsecured Proxy Servers

There are many free proxy servers. However, beginners may connect to them without proper credentials.

There are several types of proxy servers, so you can always find one that meets your requirements. You may search for proxies without knowing their source, but remember that proxies collect information and redirect it through an alternative IP address.

Free proxies are great for browsing the internet, but they are not secure. A malicious proxy can modify the HTML of the requested web page and provide false information, and it may also go offline and block your IP address. To ensure reliability for web scrapers, use dedicated proxies.

7. IP Address Blocking

Do not overlook how to overcome IP blocking in web scraping. That is the last thing you want.

However, you should address this issue as soon as possible. By using a rotating proxy service, you can avoid blocking because it routes your requests through millions of residential proxies.

8. Not Changing the Web Scraping Pattern and Not Monitoring Site Changes

People rarely perform repetitive tasks when visiting a site. On the other hand, web scraping bots always follow the same path because that is in their nature. Programmed bots constantly perform the same task.

Additionally, some sites have fantastic anti-scraping mechanisms that can be used to block a bot.

Now that we have looked at some ways to avoid detection, how can you secure your bot? By randomly clicking on a web page, aimlessly moving around, and performing arbitrary actions, a bot can appear human. To ensure the bot gets the necessary information, you must carefully monitor the site and identify any changes in its layout.

9. Ignoring Headers

When requesting a site, your browser sends many headers. The headers contain information about your identity. Therefore, it is very important to be aware of them.

These headers can be used to make your web scraper appear more human. To do this, copy them and insert them into the header element of your code. Then your request will look as if it comes from a real browser.

Moreover, using User-Agent and IP rotation makes your scraper durable. By employing these techniques, you can scrape any site, whether dynamic or static.

10. Not Knowing How to Bypass CAPTCHA

Google's reCAPTCHA is used by many sites to verify whether there is human intervention in the procedure. If the test passes within a certain time, it is considered a real person, not a bot.

When doing large-scale web scraping, the site will eventually get blocked. Additionally, the site may display CAPTCHA pages instead of web pages.

You can bypass these restrictions by using CAPTCHA solving services. However, many CAPTCHA solving services are relatively slow and expensive. Therefore, you might want to reconsider the economic viability of scraping sites that require constant CAPTCHA input.

11. Using a Personal Laptop Instead of Cloud Servers

If you are scraping on a large scale, it is recommended to stop using personal laptops. This is because laptops typically have limited resources such as CPU and memory, which can lead to slowdowns or even failures.

Instead, consider using cloud servers. Cloud servers usually have more resources than laptops, so they can handle large web scraping operations more efficiently.

Additionally, cloud servers can be easily scaled to meet your needs. This way, you can adjust your web scraping operations as requirements change.

12. Not Factoring in Other Elements That Require Increased Request Volume

Therefore, when scaling web scraping, be sure to account for the need to increase proxy pool, memory, etc. This ensures your system can handle the increased load without issues. If you do not consider other factors when scaling request volume, you will likely experience degraded performance and stability in your web scraping system.

Doing Everything Yourself is a Difficult Path

Doing everything yourself is a long and drawn-out path to scaling web scraping. But unfortunately, it is not the best way. It takes too much time.

It is risky and can lead to being blocked. There are more efficient ways to scale and quickly achieve the desired results.

Are You Ready for a Simpler and More Efficient Method?

There is a simple way to scrape the internet. One of the most significant advantages of simple web scraping is that it requires no effort. It requires no technical knowledge and can be performed by anyone with basic computer skills.

Moreover, it is an effective way to collect data from sites that are difficult or impossible to access manually. For example, you can use it to collect data from sites with restricted access rights, those that do not allow login, or those that require complex navigation.