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This article mainly explains "how to learn Python crawler with zero foundation". Interested friends may wish to take a look at it. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn "Zero basic how to learn Python Crawler"!

How to learn crawler skills with zero foundation? For the confused beginners, the most important thing in the initial learning stage of crawler technology is to make clear the learning path and find the right learning method. only in this way, under the supervision of good learning habits, the late systematic learning will get twice the result with half the effort.

To write a crawler with Python, you first need to know Python, understand the basic syntax, and know how to use functions, classes, and common data structures such as list and dict. As an entry crawler, you need to understand the basic principles of the HTTP protocol. Although the HTTP specification can not be written in a book, the in-depth content can be read slowly later, and it will be easier and easier to learn in the later stage with the combination of theory and practice. With regard to the specific steps of crawler learning, I have probably listed the following parts, which you can refer to:

Basic knowledge of web crawler:

The definition of crawler

The role of reptiles

Http protocol

Basic package grabbing tool (Fiddler) is used

Python module implements crawlers:

Explanation of the general function of urllib3, requests, lxml and bs4 modules

Use requests module get to get static page data

Use requests module post to get static page data

Using requests module to get ajax dynamic page data

Use the requests module to simulate login to the website

Using Tesseract for CAPTCHA recognition

Scrapy framework and Scrapy-Redis:

General description of the Scrapy crawler framework

Scrapy spider class

Scrapy item and pipeline

Scrapy CrawlSpider class

Implementation of distributed crawler through Scrapy-Redis

Crawl data with automated testing tools and browsers:

Explanation and simple example of Selenium + PhantomJS

Selenium + PhantomJS to realize website login

Selenium + PhantomJS to realize dynamic page data crawling

The actual combat of the reptile project:

Distributed crawler + Elasticsearch to build search engine

At this point, I believe you have a deeper understanding of "Zero basic how to learn Python crawler". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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