What are the types of web crawlers in Python?

There are various types of web crawlers in Python, including library-based crawlers and framework-based crawlers. Library-based crawlers use Python's web request libraries (e.g., requests) and parsing libraries (e.g., BeautifulSoup) to send requests and parse web content. This crawler is relatively simple to develop and is suitable for small-scale data collection tasks.

Framework-based crawlers are developed using Python web crawler frameworks such as scrapy. This crawler has more powerful features and greater flexibility to handle large-scale data collection tasks and provides more functionality and scalability. Octopus Collector is a comprehensive, simple and widely applicable Internet data collector.

If you need to collect data, Octopus Collector can provide you with intelligent identification and flexible custom collection rule settings to help you quickly obtain the data you need. To learn more about the functions and cooperation cases of octopus collectors, please go to the official website for more details.

General purpose web crawler.

General web crawlers have high requirements for hardware configuration, a large number and range of crawls, and do not have too high requirements for the order of crawled pages, but due to the parallel working mode, it takes a long time to refresh crawled pages.

Incremental web crawlers.

Incremental web crawler refers to a crawler that only crawls a changed web page or takes incremental updates to the web page that has been **, and this type of crawler can ensure the update of the crawled page to a certain extent.

Deep web crawlers.

The amount of information stored in deep web pages is very large, almost hundreds of times the amount of information on surface web pages, and deep web crawlers are crawlers specially developed for deep web pages.

Focus on web crawlers.

Focused web crawler refers to a web crawler that crawls pre-set topic-related pages in a targeted manner, which has lower hardware requirements than general web crawlers, and the data captured has higher verticality, which can meet the needs of some specific groups of people.

Web crawler is a program that automatically extracts web pages, which is an important component of search engines from the World Wide Web. Traditional crawlers start from the URL of one or more initial web pages, obtain the URL on the initial web page, and in the process of crawling the web page, continuously extract new URLs from the current page and put them in the queue until a certain stop condition of the system is met.

The URL of the web page to be crawled next will be selected from the queue according to a certain search policy, and the above process will be repeated until a certain condition of the system is reached. In addition, all web pages crawled by crawlers will be stored by the system, analyzed, filtered, and indexed for later query and retrieval.

Crawler generally refers to the scraping of network resources, due to the script characteristics of python, easy to configure the processing of characters is very flexible, python has a wealth of network scraping modules, so the two are often linked togetherpython is called crawler.

The architecture of the python crawler consists of:

The Python workflow is as follows:

Python is a cross-platform computer programming language. is a high-level scripting language that combines interpreted, compiled, interactive, and object-oriented.

Web crawlers, also known as web spiders, web ants, web robots, etc., can automatically browse information in the network, of course, when browsing information, you need to follow the rules we have formulated, these rules we call web crawler algorithms. Using python, it is easy to write a crawler program for automatic retrieval of Internet information.

A web crawler is a program or script that automatically scrapes information from the World Wide Web according to certain rules. Other names that are not commonly used are ants, auto-indexes, emulators, or worms.

Generally speaking, we compare the Internet to a big spider web, and each site resource is compared to a node on the spider web, and the crawler is like a spider, according to the designed routes and rules, find the target node in this spider web, and obtain resources. If you want to learn, you can go to a public consultation, and the python course is still good.

First of all, you must know that the python crawler is a program, and the purpose of this program is to crawl the information resources of the World Wide Web, such as search engines such as Google that you use daily, and the search results all rely on crawlers to obtain them regularly.

Understanding a python crawler is inseparable from understanding the basic principle of crawler, and let's explain this principle next.

The process of requesting a web page is divided into two parts:

1.request: Every web page that is displayed in front of the user must go through this step, which is to send an access request to the server.

2.responseAfter receiving the user's request, the server will verify the validity of the request, and then send the content of the response to the user (client), and the client receives the content of the server's response and displays the content, which is the web page request we are familiar with, as shown in the figure.

There are also two ways to request a web page:2. post

Compared with the GET method, it has the ability to upload parameters in the form of a form, so you can modify the information in addition to querying information.

Therefore, before writing a crawler, you must first determine who to send the request to and in what way. Vertical web crawler: crawls for specific domain topics, such as vertical crawlers that crawl ** directories and chapters.

Incremental web crawler: Updates the crawled web pages in real time.

Without wanting to talk about these general concepts, let's take an example of obtaining web content, starting from the crawler technology itself, to talk about web crawlers, the steps are as follows:

Simulate a request for a web resource.

Extract the target element from the HTML.

Data persistence.

What is a crawler, this is a crawler:

"Let's follow the steps mentioned above to complete a simple bot"""

import requests

from bs4 import beautifulsoup

Crawlers'Step 1 Initiate a GET request.

res = Step 2: Extract the HTML and parse the data you want to get, e.g. get the title

soup = beautifulsoup(, "lxml")

Output. title =

The third step is persistence, such as saving to a local computer.

with open('', 'w') as fp:

Add less than 20 lines of comments** and you're done with a crawler, easy.

You'll be proficient in Python and become a sought-after talent of the future.

Beginner's knowledge of Python.

Python communication circles.

Crawling other people's data, python can do everything when it comes to crawling.

It is used to collect data on the Internet, and its behavior is like a spider, so it is called a crawlerpython crawler, and it is a web crawler program written in the python programming language.

So if you're interested in data collection, you can play crawler and you won't be disappointed.

A web crawler is a program or script that automatically scrapes information from the World Wide Web according to a set of rules.

Python bots can be used to collect data. Since a bot is a program that runs very fast and doesn't get tired of repetitive things, it becomes very simple and fast to get a lot of data with a crawler.

IP HTTP crawler (Web crawler) is a program or script that automatically extracts information from the World Wide Web according to certain rules, and they are widely used in Internet search engines or other similar websites, which can automatically collect all the pages they can access to obtain or update the content and retrieval methods of these. Functionally, crawlers are generally divided into three parts: data collection, processing, and storage. Traditional crawlers start from the URL of one or several initial web pages, obtain the URL on the initial web page, and in the process of crawling, continuously extract new URLs from the current page and put them into the queue until a certain stop condition of the system is met.

The workflow of the spotlight crawler is more complex, and it needs to filter the links that are not related to the topic according to a certain HTTP analysis algorithm, keep the useful links and put them into the URL queue waiting to be crawled. It will then select the URL to crawl next from the queue based on a certain search policy, and repeat the above process until it stops when a certain condition of the system is reached. In addition, all the ** crawled by the crawler will be stored by the system, analyzed, filtered, and indexed for subsequent query and retrieval; For focused crawlers, the analysis results obtained from this process may also provide feedback and guidance for future crawling processes.

Hello dear! I'm glad to answer for you: What are the characteristics of python that are suitable for crawlersAnswer: Hello dear <>

Python is a very good programming language, easy to understand, suitable for beginners, especially in the field of crawlers has unique advantages, has become the preferred programming language. Python is a computer programming language that is a dynamic, object-oriented scripting language. Python was originally designed to write automated scripts (shells), and is increasingly being used for independent, large-scale projects as versions are updated and new features are added to the language.

Crawlers generally scrape network resources, because of the python script characteristics, stupid hall python is easy to configure, very flexible for character processing, python has a wealth of web scraping templates, so that the two rotten mountains can be well linked together.