A Beginner’s Guide to learn web scraping with python!

Web Scraping with Python

Let’s say you need to scrape a lot of information from the web, and time is of the essence. What alternative would there be to manually accessing each website and retrieving the information? “Web Scraping” is the technique that can be used. Web scraping merely facilitates and accelerates the process.

In this article on Web Scraping with Python, you will learn about web scraping in brief and see how to extract data from a website with a demonstration. I will be covering the following topics:

• • • Why is Web Scraping Used?
    • What Is Web Scraping?
    • Is Web Scraping Legal?
    • Why is Python Good For Web Scraping?
    • How Do You Scrape Data From A Website?
    • Libraries used for Web Scraping
    • Web Scraping Example : Scraping Flipkart Website

Why is Web Scraping Used?

Web scraping is used to collect large information from websites. You can also find more in-depth concepts about Web Scraping on Edureka’s Python course. But why does someone have to collect such large data from websites? To know about this, let’s look at the applications of web scraping:

• Price Comparison: Services such as ParseHub use web scraping to collect data from online shopping websites and use it to compare the prices of products.
• Email address gathering: Many companies that use email as a medium for marketing, use web scraping to collect email ID and then send bulk emails.
• Social Media Scraping: Web scraping is used to collect data from Social Media websites such as Twitter to find out what’s trending.
• Research and Development: Web scraping is used to collect a large set of data (Statistics, General Information, Temperature, etc.) from websites, which are analyzed and used to carry out Surveys or for R&D.
• Job listings: Details regarding job openings, interviews are collected from different websites and then listed in one place so that it is easily accessible to the user.

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What is Web Scraping?

Web scraping is one of the automated processes for gathering extensive information from the World Wide Web. The information found on the websites is disorganized. In order to store this data in a more organized fashion, web scraping is a useful tool. Online services, application programming interfaces (APIs), and custom code are just some of the options for scraping websites. This article will show how to use Python to perform web scraping.

Is Web Scraping Legal?

Talking about whether web scraping is legal or not, some websites allow web scraping and some don’t. To know whether a website allows web scraping or not, you can look at the website’s “robots.txt” file. You can find this file by appending “/robots.txt” to the URL that you want to scrape. For this example, I am scraping Flipkart website. So, to see the “robots.txt” file, the URL is www.flipkart.com/robots.txt.

Why is Python Good for Web Scraping?

Here is the list of features of Python which makes it more suitable for web scraping.

• Ease of Use: Python programming is simple to code. You do not have to add semi-colons “;” or curly-braces “{}” anywhere. This makes it less messy and easy to use.
• Large Collection of Libraries: Python has a huge collection of libraries such as Numpy, Matlplotlib, Pandas etc., which provides methods and services for various purposes. Hence, it is suitable for web scraping and for further manipulation of extracted data.
• Dynamically typed: In Python, you don’t have to define datatypes for variables, you can directly use the variables wherever required. This saves time and makes your job faster.
• Easily Understandable Syntax: Python syntax is easily understandable mainly because reading a Python code is very similar to reading a statement in English. It is expressive and easily readable, and the indentation used in Python also helps the user to differentiate between different scope/blocks in the code. 
• Small code, large task: Web scraping is used to save time. But what’s the use if you spend more time writing the code? Well, you don’t have to. In Python, you can write small codes to do large tasks. Hence, you save time even while writing the code.
• Community: What if you get stuck while writing the code? You don’t have to worry. Python community has one of the biggest and most active communities, where you can seek help from.

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How Do You Scrape Data From A Website?

When you run the code for web scraping, a request is sent to the URL that you have mentioned. As a response to the request, the server sends the data and allows you to read the HTML or XML page. The code then, parses the HTML or XML page, finds the data and extracts it. 

To extract data using web scraping with python, you need to follow these basic steps:

1. Find the URL that you want to scrape
2. Inspecting the Page
3. Find the data you want to extract
4. Write the code
5. Run the code and extract the data
6. Store the data in the required format 

Now let us see how to extract data from the Flipkart website using Python.

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Libraries used for Web Scraping 

As we know, Python is has various applications and there are different libraries for different purposes. In our further demonstration, we will be using the following libraries:

• Selenium:  Selenium is a web testing library. It is used to automate browser activities.
• BeautifulSoup: Beautiful Soup is a Python package for parsing HTML and XML documents. It creates parse trees that is helpful to extract the data easily.
• Pandas: Pandas is a library used for data manipulation and analysis. It is used to extract the data and store it in the desired format. 

Web Scraping Example : Scraping Flipkart Website

Pre-requisites:

• Python 2.x or Python 3.x with Selenium, BeautifulSoup, pandas libraries installed
• Google-chrome browser
• Ubuntu Operating System

Let’s get started!

Step 1: Find the URL that you want to scrape

For this example, we are going scrape Flipkart website to extract the Price, Name, and Rating of Laptops. The URL for this page is https://www.flipkart.com/laptops/~buyback-guarantee-on-laptops-/pr?sid=6bo%2Cb5g&uniqBStoreParam1=val1&wid=11.productCard.PMU_V2.

Step 2: Inspecting the Page

The data is usually nested in tags. So, we inspect the page to see, under which tag the data we want to scrape is nested. To inspect the page, just right click on the element and click on “Inspect”.

When you click on the “Inspect” tab, you will see a “Browser Inspector Box” open.

Step 3: Find the data you want to extract

Let’s extract the Price, Name, and Rating which is in the “div” tag respectively.

Step 4: Write the code

First, let’s create a Python file. To do this, open the terminal in Ubuntu and type gedit <your file name> with .py extension.

I am going to name my file “web-s”. Here’s the command:

gedit web-s.py

Now, let’s write our code in this file. 

First, let us import all the necessary libraries:

from selenium import webdriver
from BeautifulSoup import BeautifulSoup
import pandas as pd

To configure webdriver to use Chrome browser, we have to set the path to chromedriver

driver = webdriver.Chrome("/usr/lib/chromium-browser/chromedriver")

Refer the below code to open the URL:

products=[] #List to store name of the product
prices=[] #List to store price of the product
ratings=[] #List to store rating of the product
driver.get("https://www.flipkart.com/laptops/~buyback-guarantee-on-laptops-/pr?sid=6bo%2Cb5guniq")

Now that we have written the code to open the URL, it’s time to extract the data from the website. As mentioned earlier, the data we want to extract is nested in <div> tags. So, I will find the div tags with those respective class-names, extract the data and store the data in a variable. Refer the code below:

content = driver.page_source
soup = BeautifulSoup(content)
for a in soup.findAll('a',href=True, attrs={'class':'_31qSD5'}):
name=a.find('div', attrs={'class':'_3wU53n'})
price=a.find('div', attrs={'class':'_1vC4OE _2rQ-NK'})
rating=a.find('div', attrs={'class':'hGSR34 _2beYZw'})
products.append(name.text)
prices.append(price.text)
ratings.append(rating.text) 

Step 5: Run the code and extract the data

To run the code, use the below command:

python web-s.py

Step 6: Store the data in a required format

After extracting the data, you might want to store it in a format. This format varies depending on your requirement. For this example, we will store the extracted data in a CSV (Comma Separated Value) format. To do this, I will add the following lines to my code:

df = pd.DataFrame({'Product Name':products,'Price':prices,'Rating':ratings}) 
df.to_csv('products.csv', index=False, encoding='utf-8')

Now, I’ll run the whole code again.

A file name “products.csv” is created and this file contains the extracted data.

Scrape and Parse Text From Websites

To scrape and parse text from websites in Python, you can use the requests library to fetch the HTML content of the website and then use a parsing library like BeautifulSoup or lxml to extract the relevant text from the HTML. Here’s a step-by-step guide:

Step 1: Import necessary modules

import requests 
from bs4 import BeautifulSoup
import re

Step 2: Fetch the HTML content of the website using `requests`

url = 'https://example.com'; # Replace this with the URL of the website you want to scrape
response = requests.get(url)
# Check if the request was successful
if response.status_code == 200:
html_content = response.content
else:
 print("Failed to fetch the website.")
exit()

Step 3: Parse the HTML content using `BeautifulSoup`

# Parse the HTML content with BeautifulSoup
soup = BeautifulSoup(html_content, 'html.parser')

 
Step 4: Extract the text from the parsed HTML using string methods

# Find all the text elements (e.g., paragraphs, headings, etc.) you want to scrape
text_elements = soup.find_all(['p', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'span'])
# Extract the text from each element and concatenate them into a single string
scraped_text = ' '.join(element.get_text() for element in text_elements)
print(scraped_text)

Step 5: Extract text from HTML using regular expressions

</pre>
<span> </span></pre>
<span style="font-weight: 400;">Note: The regular expression in Step 5 is a simple pattern that matches any HTML tag and removes them from the HTML content. In real-world scenarios, you may need more complex regular expressions depending on the structure of the HTML.</span>

<strong>Check Your Understanding:</strong>

<span style="font-weight: 400;">Now that you have built your web scraper, you can use either the string method approach or the regular expression approach to extract text from websites. Remember to use web scraping responsibly and adhere to website policies and legal restrictions. Always review the website's terms of service and robots.txt file before scraping any website. Additionally, excessive or unauthorized scraping may put a strain on the website's server and is generally considered unethical.</span>
<h2>Use an HTML Parser for Web Scraping in Python</h2>
<span style="font-weight: 400;">Here are the steps to use an HTML parser like Beautiful Soup for web scraping in Python:</span>

<b>Step 1: Install Beautiful Soup</b>

<span style="font-weight: 400;">Make sure you have the Beautiful Soup library installed. If not, you can install it using `pip`:</span>

<span style="font-weight: 400;">```bash</span>

<span style="font-weight: 400;">pip install beautifulsoup4</span>

<span style="font-weight: 400;">```</span>

<b>Step 2: Create a BeautifulSoup Object</b>

<span style="font-weight: 400;">Import the necessary modules and create a BeautifulSoup object to parse the HTML content of the website.</span>

<span style="font-weight: 400;">

Step 4: Check Your Understanding
Now that you have a BeautifulSoup object (`soup`), you can use its various methods to extract specific data from the HTML. For example, you can use `soup.find()` to find the first occurrence of a specific HTML element, `soup.find_all()` to find all occurrences of an element, and `soup.select()` to use CSS selectors to extract elements.
Here’s an example of how to use `soup.find()` to extract the text of the first paragraph (`<p>`) tag:

<span style="font-weight: 400;"># Find the first paragraph tag and extract its text</span>

<span style="font-weight: 400;">first_paragraph = soup.find('p').get_text()</span>
<h2></h2>
<span style="font-weight: 400;">print(first_paragraph)</span>

You can explore more methods available in the BeautifulSoup library to extract data from the HTML content as needed for your web scraping task.
Remember to use web scraping responsibly, adhere to website policies and legal restrictions, and review the website’s terms of service and robots.txt file before scraping any website. Additionally, excessive or unauthorized scraping may put a strain on the website’s server and is generally considered unethical.
Interact With HTML Forms
Certainly! Here are the steps to interact with HTML forms using MechanicalSoup in Python:
 
Step 1: Install MechanicalSoup
Ensure you have the MechanicalSoup library installed. If not, you can install it using `pip`:
 
“`bash
pip install MechanicalSoup
“`
 
Step 2: Create a Browser Object
Import the necessary modules and create a MechanicalSoup browser object to interact with the website.
 
 
</span>

<span style="font-weight: 400;">import mechanicalsoup</span>

<span style="font-weight: 400;">
 
 
Step 3: Submit a Form with MechanicalSoup
Create a browser object and use it to submit a form on a specific webpage.
 
 
</span>

<span style="font-weight: 400;"># Create a MechanicalSoup browser object</span>

<span style="font-weight: 400;">browser = mechanicalsoup.StatefulBrowser()</span>

<b></b>

<span style="font-weight: 400;"># Navigate to the webpage with the form</span>

<span style="font-weight: 400;">url = 'https://example.com/form-page' # Replace this with the URL of the webpage with the form</span>

<span style="font-weight: 400;">browser.open(url)</span>

<b></b>

<span style="font-weight: 400;"># Fill in the form fields</span>

<span style="font-weight: 400;">form = browser.select_form() # Select the form on the webpage</span>

<span style="font-weight: 400;">form['username'] = 'your_username'; # Replace 'username' with the name attribute of the username input field</span>

<span style="font-weight: 400;">form['password'] = 'your_password'; # Replace 'password' with the name attribute of the password input field</span>

<b></b>

<span style="font-weight: 400;"># Submit the form</span>

<span style="font-weight: 400;">browser.submit_selected()</span>

<span style="font-weight: 400;">
 
Step 4: Check Your Understanding
In this example, we used MechanicalSoup to create a browser object (`browser`) and navigate to a webpage with a form. We then selected the form using `browser.select_form()`, filled in the username and password fields using `form[‘username’]` and `form[‘password’]`, and finally submitted the form using `browser.submit_selected()`.
 
With these steps, you can interact with HTML forms programmatically. MechanicalSoup is a powerful tool for automating form submissions, web scraping, and interacting with websites that have forms.
Remember to use web scraping and form submission responsibly, adhere to website policies and legal restrictions, and review the website’s terms of service before interacting with its forms. Additionally, make sure that the website allows automated interactions and that you are not violating any usage policies. Unauthorized and excessive form submissions can cause strain on the website’s server and may be considered unethical.
Interact With Websites in Real Time
Interacting with websites in real-time typically involves performing actions on a webpage and receiving immediate feedback or responses without requiring a full page reload. There are several methods to achieve real-time interactions with websites, depending on the use case and technologies involved. Here are some common approaches:
 
 JavaScript and AJAX: JavaScript is a powerful client-side scripting language that allows you to manipulate the DOM (Document Object Model) of a webpage. AJAX (Asynchronous JavaScript and XML) enables you to make asynchronous HTTP requests to the server without reloading the entire page. With JavaScript and AJAX, you can perform actions like submitting forms, updating content, and fetching data from the server in real-time.
 
 WebSockets: WebSockets provide full-duplex communication channels over a single TCP connection, enabling real-time, bidirectional communication between a client and a server. WebSockets are ideal for applications that require continuous data streams or real-time updates, such as chat applications, live notifications, and collaborative platforms.
 
 Server-Sent Events (SSE): SSE is a standard that enables a server to send real-time updates to a client over an HTTP connection. Unlike WebSockets, SSE is unidirectional (server to client), making it suitable for scenarios where the client only needs to receive updates from the server without sending data back.
 
 WebRTC: Web Real-Time Communication (WebRTC) is a technology that allows peer-to-peer communication between browsers. It is commonly used for video conferencing, audio calls, and other real-time media interactions directly between users.
 
 Push Notifications: Push notifications are messages sent from a server to a client’s device, notifying them of new events or updates. They are commonly used on mobile devices and web browsers to deliver real-time alerts or updates to users, even when the application is not open.
 
 Single Page Applications (SPAs): SPAs are web applications that load a single HTML page and dynamically update the content as the user interacts with the page. SPAs use JavaScript frameworks like React, Angular, or Vue.js to manage state and handle real-time updates efficiently.
Overall, the choice of the approach for real-time interactions with websites depends on the specific requirements and technologies involved. JavaScript, AJAX, WebSockets, SSE, WebRTC, and push notifications are some of the common technologies used to enable real-time communication and interactivity on modern web applications.
I hope you guys enjoyed this article on “Web Scraping with Python”. I hope this blog was informative and has added value to your knowledge. Now go ahead and try Web Scraping. Experiment with different modules and applications of Python. 
If you wish to know about Web Scraping With Python on Windows platform, then the below video will help you understand how to do it or you can also join our Python Master course.
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