Detailed explanation of requirements.txt in python

Introduction

The Python project must contain a requirements.txt file to record all dependent packages and their precise version numbers. for deployment in new environments.

The main writing methods are as follows

pip freeze > requirements.txt # 生成requirements.txt
pip install -r requirements.txt # 从requirements.txt安装依赖

Supported writing methods

-r base.txt # base.txt下面的所有包
pypinyin==0.12.0 # 指定版本（最日常的写法）
django-querycount>=0.5.0 # 大于某个版本
django-debug-toolbar>=1.3.1,<=1.3.3 # 版本范围
ipython # 默认（存在不替换，不存在安装最新版）

Third-party tool generation

pip freeze will come with some unnecessary packages, as well as packages that some packages depend on~

pipreqs automatically analyzes packages referenced in the project. When automatically building the Django project, the Mysql package was ignored, and the version was also very strange; and when searching online, an error message jumped out when a 404 was encountered.