setV：一個管理 Python 虛擬環境的 Bash 函數

這一年多來，我的 bash_scripts 項目中悄悄隱藏這 setV，但現在是時候該公開了。setV 是一個 Bash 函數，我可以用它代替 virtualenvwrapper。它提供了使你能夠執行以下操作的基本功能：

• 默認使用 Python 3
• 創建一個新的虛擬環境
• 使用帶有 -p（或 --python）的自定義 Python 路徑來創建新的虛擬環境
• 刪除現有的虛擬環境
• 列出所有現有的虛擬環境
• 使用製表符補全（以防你忘記虛擬環境名稱）

安裝

要安裝 setV，請下載該腳本：

curl https://gitlab.com/psachin/setV/raw/master/install.sh

審核一下腳本，然後運行它：

sh ./install.sh

當安裝 setV 時，安裝腳本會要求你引入（source）一下 ~/.bashrc 或 ~/.bash_profile 的配置，根據你的喜好選擇一個。

用法

基本的命令格式是 setv。

創建虛擬環境

setv --new rango  # setv -n rango

# 或使用定製的 Python 路徑
setv --new --python /opt/python/python3 rango  # setv -n -p /opt/python/python3 rango

激活已有的虛擬環境

setv VIRTUAL_ENVIRONMENT_NAME

# 示例
setv rango

列出所有的虛擬環境

setv --list
# 或
setv [TAB] [TAB]

刪除虛擬環境

setv --delete rango

切換到另外一個虛擬環境

# 假設你現在在 'rango'，切換到 'tango'
setv tango

製表符補完

如果你不完全記得虛擬環境的名稱，則 Bash 式的製表符補全也可以適用於虛擬環境名稱。

參與其中

setV 在 GNU GPLv3下開源，歡迎貢獻。要了解更多信息，請訪問它的 GitLab 存儲庫中的 setV 的 README 的貢獻部分。

setV 腳本

#!/usr/bin/env bash
# setV - A Lightweight Python virtual environment manager.
# Author: Sachin (psachin) <iclcoolster@gmail.com>
# Author&apos;s URL: https://psachin.gitlab.io/about
#
# License: GNU GPL v3, See LICENSE file
#
# Configure(Optional):
# Set `SETV_VIRTUAL_DIR_PATH` value to your virtual environments
# directory-path. By default it is set to &apos;~/virtualenvs/&apos;
#
# Usage:
# Manual install: Added below line to your .bashrc or any local rc script():
# # source /path/to/virtual.sh
# #
# Now you can &apos;activate&apos; the virtual environment by typing
# $ setv <YOUR VIRTUAL ENVIRONMENT NAME>
#
# For example:
# $ setv rango
#
# or type:
# setv [TAB] [TAB]  (to list all virtual envs)
#
# To list all your virtual environments:
# $ setv --list
#
# To create new virtual environment:
# $ setv --new new_virtualenv_name
#
# To delete existing virtual environment:
# $ setv --delete existing_virtualenv_name
#
# To deactivate, type:
# $ deactivate

# Path to virtual environment directory
SETV_VIRTUAL_DIR_PATH="$HOME/virtualenvs/"
# Default python version to use. This decides whether to use `virtualenv` or `python3 -m venv`
SETV_PYTHON_VERSION=3  # Defaults to Python3
SETV_PY_PATH=$(which python${SETV_PYTHON_VERSION})

function _setvcomplete_()
{
    # Bash-autocompletion.
    # This ensures Tab-auto-completions work for virtual environment names.
    local cmd="${1##*/}" # to handle command(s).
                         # Not necessary as such. &apos;setv&apos; is the only command

    local word=${COMP_WORDS[COMP_CWORD]} # Words thats being completed
    local xpat=&apos;${word}&apos;                 # Filter pattern. Include
                                         # only words in variable &apos;$names&apos;
    local names=$(ls -l "${SETV_VIRTUAL_DIR_PATH}" | egrep &apos;^d&apos; | awk -F " " &apos;{print $NF}&apos;) # Virtual environment names

    COMPREPLY=($(compgen -W "$names" -X "$xpat" -- "$word")) # compgen generates the results
}

function _setv_help_() {
    # Echo help/usage message
    echo "Usage: setv [OPTIONS] [NAME]"
    echo Positional argument:
    echo -e "NAME                       Activate virtual env."
    echo Optional arguments:
    echo -e "-l, --list                 List all Virtual Envs."
    echo -e "-n, --new NAME             Create a new Python Virtual Env."
    echo -e "-d, --delete NAME          Delete existing Python Virtual Env."
    echo -e "-p, --python PATH          Python binary path."
}

function _setv_custom_python_path()
{
    if [ -f "${1}" ];
    then
        if [ "`expr $1 : &apos;.*python([2,3])&apos;`" = "3" ];
        then
            SETV_PYTHON_VERSION=3
        else
            SETV_PYTHON_VERSION=2
        fi
        SETV_PY_PATH=${1}
        _setv_create $2
    else
        echo "Error: Path ${1} does not exist!"
    fi
}

function _setv_create()
{
    # Creates new virtual environment if ran with -n|--new flag
    if [ -z ${1} ];
    then
        echo "You need to pass virtual environment name"
        _setv_help_
    else
        echo "Creating new virtual environment with the name: $1"

        if [ ${SETV_PYTHON_VERSION} -eq 3 ];
        then
            ${SETV_PY_PATH} -m venv ${SETV_VIRTUAL_DIR_PATH}${1}
        else
            virtualenv -p ${SETV_PY_PATH} ${SETV_VIRTUAL_DIR_PATH}${1}
        fi

        echo "You can now activate the Python virtual environment by typing: setv ${1}"
    fi
}

function _setv_delete()
{
    # Deletes virtual environment if ran with -d|--delete flag
    # TODO: Refactor
    if [ -z ${1} ];
    then
        echo "You need to pass virtual environment name"
        _setv_help_
    else
        if [ -d ${SETV_VIRTUAL_DIR_PATH}${1} ];
        then
            read -p "Really delete this virtual environment(Y/N)? " yes_no
            case $yes_no in
                Y|y) rm -rvf ${SETV_VIRTUAL_DIR_PATH}${1};;
                N|n) echo "Leaving the virtual environment as it is.";;
                *) echo "You need to enter either Y/y or N/n"
            esac
        else
            echo "Error: No virtual environment found by the name: ${1}"
        fi
    fi
}

function _setv_list()
{
    # Lists all virtual environments if ran with -l|--list flag
    echo -e "List of virtual environments you have under ${SETV_VIRTUAL_DIR_PATH}:n"
    for virt in $(ls -l "${SETV_VIRTUAL_DIR_PATH}" | egrep &apos;^d&apos; | awk -F " " &apos;{print $NF}&apos;)
    do
        echo ${virt}
    done
}

function setv() {
    # Main function
    if [ $# -eq 0 ];
    then
        _setv_help_
    elif [ $# -le 3 ];
    then
        case "${1}" in
            -n|--new) _setv_create ${2};;
            -d|--delete) _setv_delete ${2};;
            -l|--list) _setv_list;;
            *) if [ -d ${SETV_VIRTUAL_DIR_PATH}${1} ];
               then
                   # Activate the virtual environment
                   source ${SETV_VIRTUAL_DIR_PATH}${1}/bin/activate
               else
                   # Else throw an error message
                   echo "Sorry, you don&apos;t have any virtual environment with the name: ${1}"
                   _setv_help_
               fi
               ;;
        esac
    elif [ $# -le 5 ];
    then
        case "${2}" in
            -p|--python) _setv_custom_python_path ${3} ${4};;
            *) _setv_help_;;
        esac
    fi
}

# Calls bash-complete. The compgen command accepts most of the same
# options that complete does but it generates results rather than just
# storing the rules for future use.
complete  -F _setvcomplete_ setv

via: https://opensource.com/article/20/1/setv-bash-function

作者：Sachin Patil 選題：lujun9972 譯者：wxy 校對：wxy

本文由 LCTT 原創編譯，Linux中國 榮譽推出

本文轉載來自 Linux 中國: https://github.com/Linux-CN/archive