What libraries need to be installed to learn Python web crawler?
The following are the relevant libraries involved in Python crawlers
Request library, parsing library, storage library, tool library
1. Request library: urllib/re/requests
(1) urllib/re is the library that comes with python by default. It can be verified by the following command:
No error message is output, indicating that the environment is normal
(2) requests installation
2.1 Open CMD, enter pip3 install requests
2.2 Wait for installation , Verification
(3) selenium installation (driving the browser for website access behavior)
3.1 Open CMD and enter pip3 install selenium
3.2 Install chromedriver
Website: https://npm.taobao.org/
Extract the downloaded compressed package and put the exe into D:\Python3.6.0 \Scripts\
This path only needs to be in the PATH variable
3.3 Wait for the installation to be completed, verify
and press Enter to pop up chrome browser interface
3.4 Install other browsers
Interfaceless browser phantomjs
Download URL: http://phantomjs.org/
Download After completion, unzip it, put the entire directory into D:\Python3.6.0\Scripts\, and add the path to the bin directory to the PATH variable
Verification:
Open CMD
2. Parsing library:
2.1 lxml (XPATH)
Open CMD and enter pip3 install lxml or download from https://pypi.python.org, For example, lxml-4.1.1-cp36-cp36m-win_amd64.whl (md5), first download the whl file, and execute pip3 install on the command line. File name.whl
2.2 beautifulsoup
To open CMD, you need to install lxml first
pip3 install beautifulsoup4
2.3 pyquery (similar to jquery syntax)
Open CMD , pip3 install pyquery
Verify the installation results
3. Repository
3.1 pymysql (operating MySQL, relational database)
Installation: pip3 install pymysql, test after installation:
3.2 pymongo (operating MongoDB, key-value)
Installation pip3 install pymongo
Verification
##3.3 redis (distributed crawler, maintain crawling queue) Installation: pip3 install redisThe above is the detailed content of What packages should be installed for python crawler?. For more information, please follow other related articles on the PHP Chinese website!