Scrapy Cores
Understand the essential components of the Scrapy framework, including the Spider class, Request and Response handling, and LinkExtractor usage. Learn how to customize parameters for focused crawling and effective data extraction from websites, enabling you to build sophisticated scraping solutions.
We'll cover the following...
Now that we learned about Scrapy, let's dive into more detail about its core modules.
The Spider Class
The scrapy.Spider class is the heart of any Scrapy project. It defines how to crawl and extract information from a website. Let's delve into some of the critical parameters that can be utilized within this class to fine-tune our web scraping process.
nameIt uniquely identifies our spider, which is crucial when running multiple spiders within a single project. This name differentiates the output files, logs, and other spider-related resources. We should choose a descriptive and meaningful name for our spider.
allowed_domainsThe
allowed_domainsparameter is a list of domains that our spider is allowed to crawl. Any links outside these domains will be ignored. This handy feature ensures our spider stays focused on the relevant content.
start_urlsThis parameter is a list of URLs where the spider begins crawling.
start_urlsserves as a shortcut forstart_requests()functions. If this parameter is defined and we didn't define the start_requests() function, Scrapy will internally initialize this function for us with this list of URLs.
custom_settingsSince Scrapy is designed to run multiple spiders, it gives ...