Extracting Data from one Webpage

The code for web scraping is written in the spider code file. To create the spider file, we will make use of the ‘genspider’ command. Please note, that this command is executed at the same level where scrapy.cfg file is present. 

We are scraping all quotes present, on ‘http://quotes.toscrape.com/’. Hence, we will run the command as:

scrapy genspider gfg_spilink "quotes.toscrape.com"

Execute ‘genspider’ command to create a Spider file

The above command will create a spider file, “gfg_spilink.py” in the ‘spiders’ folder. The default code, for the same, is as follows:

Python3




# Import the required libraries
import scrapy
  
# Spider class name
  
  
class GfgSpilinkSpider(scrapy.Spider):
    # Name of the spider
    name = 'gfg_spilink'
      
    # The domain to be scraped
    allowed_domains = ['quotes.toscrape.com']
      
    # The URLs to be scraped from the domain
    start_urls = ['http://quotes.toscrape.com/']
  
    # Default callback method
    def parse(self, response):
        pass


We will scrape all Quotes Title, Authors, and Tags from the website “quotes.toscrape.com”. The website landing page looks as shown below:

The landing page of “quotes.toscrape.com”

Scrapy provides us, with Selectors, to “select” parts of the webpage, desired. Selectors are CSS or XPath expressions, written to extract data from HTML documents. In this tutorial, we will make use of XPath expressions, to select the details we need. 

Let us understand the steps for writing the selector syntax in the  spider code:

  • Firstly, we will write the code in the parse() method. This is the default callback method, present in the spider class, responsible for processing the response received. The data extraction code, using Selectors, will be written here.
  • For writing the XPath expressions, we will select the element on the webpage, say Right-Click, and choose the Inspect option. This will allow us to view its CSS attributes.
  • When we right-click on the first Quote and choose Inspect, we can see it has the CSS ‘class’ attribute “quote”. Similarly, all the other quotes on the webpage have the same CSS ‘class’ attribute. It can be seen below:

Right Click first quote and check its CSS “class” attribute

Hence, the XPath expression, for the same, can be written as – quotes = response.xpath(‘//*[@class=”quote”]’). This syntax will fetch all elements, having “quote”, as the CSS ‘class’ attribute. The quotes present on further pages have the same CSS attribute. For example, the quotes present on Page 3, of the website, belong to the  ‘class’ attribute, as shown below –

The Quotes on further pages of the website belong to the same CSS class attribute

We need to fetch the Quote Title, Author, and Tags of all the Quotes. Hence, we will write XPath expressions for extracting them, in a loop. 

  • The CSS ‘class’ attribute, for Quote Title, is “text”. Hence, the XPath expression, for the same, would be – quote.xpath(‘.//*[@class=”text”]/text()’).extract_first(). The text() method, will extract the text, of the Quote title. The extract_first() method, will give the first matching value, with the CSS attribute “text”. The dot operator ‘.’ in the start, indicates extracting data, from a single quote.
  • The CSS  attributes, “class” and “itemprop”, for author element, is “author”. We can use, any of these, in the XPath expression. The syntax would be – quote.xpath(‘.//*[@itemprop=”author”]/text()’).extract(). This will extract, the Author name, where the CSS ‘itemprop’ attribute is ‘author’.
  • The CSS  attributes, “class” and “itemprop”, for tags element, is “keywords”. We can use, any of these, in the XPath expression. Since there are many tags, for any quote, looping through them, will be tedious. Hence, we will extract the CSS attribute “content”, from every quote. The XPath expression for the same is – quote.xpath(‘.//*[@itemprop=”keywords”]/@content’).extract(). This will extract, all tags values, from “content” attribute, for quotes.
  • We use ‘yield’ syntax to get the data. We can collect, and, transfer data to CSV, JSON, and other file formats, by using ‘yield’.

If we observe the code till here, it will crawl and extract data for one webpage. The code is as follows –

Python3




# Import the required libraries
import scrapy
  
# Spider class name
  
  
class GfgSpilinkSpider(scrapy.Spider):
    
    # Name of the spider
    name = 'gfg_spilink'
      
    # The domain to be scraped
    allowed_domains = ['quotes.toscrape.com']
      
    # The URLs to be scraped from the domain
    start_urls = ['http://quotes.toscrape.com/']
  
    # Default callback method
    def parse(self, response):
        
        # All quotes have CSS 'class 'attribute as 'quote'
        quotes = response.xpath('//*[@class="quote"]')
          
        # Loop through the quotes
        # selectors to fetch data for every quote
        for quote in quotes:
            
            # XPath expression to fetch
            # text of the Quote title
            # note the 'dot' operator since
            # we are extracting from single 'quote' element
            title = quote.xpath(
                './/*[@class="text"]/text()').extract_first()
              
            # XPath expression to fetch author of the Quote
            authors = quote.xpath('.//*[@itemprop="author"]/text()').extract()
              
            # XPath expression to fetch tags of the Quote
            tags = quote.xpath('.//*[@itemprop="keywords"]/@content').extract()
              
            # Yield the data desired
            yield {"Quote Text ": title, "Authors ": authors, "Tags ": tags}


How To Follow Links With Python Scrapy ?

In this article, we will use Scrapy, for scraping data, presenting on linked webpages, and, collecting the same. We will scrape data from the website ‘https://quotes.toscrape.com/’.

Similar Reads

Creating a Scrapy Project

Scrapy comes with an efficient command-line tool, also called the ‘Scrapy tool’. Commands are used for different purposes and, accept a different set of arguments, and options. To write the Spider code, we begin by creating, a Scrapy project, by executing the following command, at the terminal:...

Extracting Data from one Webpage

The code for web scraping is written in the spider code file. To create the spider file, we will make use of the ‘genspider’ command. Please note, that this command is executed at the same level where scrapy.cfg file is present....

Following Links

...

Contact Us