【shell编程入门】stable diffusion webui的webui.sh脚本解析

前言

通过webui.sh，我们可以在linux系统下安装虚拟环境，并启动stable diffuson webui。

脚本实例

#!/usr/bin/env bash
#################################################
# Please do not make any changes to this file,  #
# change the variables in webui-user.sh instead #
#################################################

SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )


# If run from macOS, load defaults from webui-macos-env.sh
if [[ "$OSTYPE" == "darwin"* ]]; then
    if [[ -f "$SCRIPT_DIR"/webui-macos-env.sh ]]
        then
        source "$SCRIPT_DIR"/webui-macos-env.sh
    fi
fi

# Read variables from webui-user.sh
# shellcheck source=/dev/null
if [[ -f "$SCRIPT_DIR"/webui-user.sh ]]
then
    source "$SCRIPT_DIR"/webui-user.sh
fi

# If $venv_dir is "-", then disable venv support
use_venv=1
if [[ $venv_dir == "-" ]]; then
  use_venv=0
fi

# Set defaults
# Install directory without trailing slash
if [[ -z "${install_dir}" ]]
then
    install_dir="$SCRIPT_DIR"
fi

# Name of the subdirectory (defaults to stable-diffusion-webui)
if [[ -z "${clone_dir}" ]]
then
    clone_dir="stable-diffusion-webui"
fi

# python3 executable
if [[ -z "${python_cmd}" ]]
then
    python_cmd="python3"
fi

# git executable
if [[ -z "${GIT}" ]]
then
    export GIT="git"
else
    export GIT_PYTHON_GIT_EXECUTABLE="${GIT}"
fi

# python3 venv without trailing slash (defaults to ${install_dir}/${clone_dir}/venv)
if [[ -z "${venv_dir}" ]] && [[ $use_venv -eq 1 ]]
then
    venv_dir="venv"
fi

if [[ -z "${LAUNCH_SCRIPT}" ]]
then
    LAUNCH_SCRIPT="launch.py"
fi

# this script cannot be run as root by default
can_run_as_root=0

# read any command line flags to the webui.sh script
while getopts "f" flag > /dev/null 2>&1
do
    case ${flag} in
        f) can_run_as_root=1;;
        *) break;;
    esac
done

# Disable sentry logging
export ERROR_REPORTING=FALSE

# Do not reinstall existing pip packages on Debian/Ubuntu
export PIP_IGNORE_INSTALLED=0

# Pretty print
delimiter="################################################################"

printf "\n%s\n" "${delimiter}"
printf "\e[1m\e[32mInstall script for stable-diffusion + Web UI\n"
printf "\e[1m\e[34mTested on Debian 11 (Bullseye), Fedora 34+ and openSUSE Leap 15.4 or newer.\e[0m"
printf "\n%s\n" "${delimiter}"

# Do not run as root
if [[ $(id -u) -eq 0 && can_run_as_root -eq 0 ]]
then
    printf "\n%s\n" "${delimiter}"
    printf "\e[1m\e[31mERROR: This script must not be launched as root, aborting...\e[0m"
    printf "\n%s\n" "${delimiter}"
    exit 1
else
    printf "\n%s\n" "${delimiter}"
    printf "Running on \e[1m\e[32m%s\e[0m user" "$(whoami)"
    printf "\n%s\n" "${delimiter}"
fi

if [[ $(getconf LONG_BIT) = 32 ]]
then
    printf "\n%s\n" "${delimiter}"
    printf "\e[1m\e[31mERROR: Unsupported Running on a 32bit OS\e[0m"
    printf "\n%s\n" "${delimiter}"
    exit 1
fi

if [[ -d .git ]]
then
    printf "\n%s\n" "${delimiter}"
    printf "Repo already cloned, using it as install directory"
    printf "\n%s\n" "${delimiter}"
    install_dir="${PWD}/../"
    clone_dir="${PWD##*/}"
fi

# Check prerequisites
gpu_info=$(lspci 2>/dev/null | grep -E "VGA|Display")
case "$gpu_info" in
    *"Navi 1"*)
        export HSA_OVERRIDE_GFX_VERSION=10.3.0
        if [[ -z "${TORCH_COMMAND}" ]]
        then
            pyv="$(${python_cmd} -c 'import sys; print(".".join(map(str, sys.version_info[0:2])))')"
            if [[ $(bc <<< "$pyv <= 3.10") -eq 1 ]] 
            then
                # Navi users will still use torch 1.13 because 2.0 does not seem to work.
                export TORCH_COMMAND="pip install torch==1.13.1+rocm5.2 torchvision==0.14.1+rocm5.2 --index-url https://download.pytorch.org/whl/rocm5.2"
            else
                printf "\e[1m\e[31mERROR: RX 5000 series GPUs must be using at max python 3.10, aborting...\e[0m"
                exit 1
            fi
        fi
    ;;
    *"Navi 2"*) export HSA_OVERRIDE_GFX_VERSION=10.3.0
    ;;
    *"Navi 3"*) [[ -z "${TORCH_COMMAND}" ]] && \
         export TORCH_COMMAND="pip install torch torchvision --index-url https://download.pytorch.org/whl/test/rocm5.6"
        # Navi 3 needs at least 5.5 which is only on the torch 2.1.0 release candidates right now
    ;;
    *"Renoir"*) export HSA_OVERRIDE_GFX_VERSION=9.0.0
        printf "\n%s\n" "${delimiter}"
        printf "Experimental support for Renoir: make sure to have at least 4GB of VRAM and 10GB of RAM or enable cpu mode: --use-cpu all --no-half"
        printf "\n%s\n" "${delimiter}"
    ;;
    *)
    ;;
esac
if ! echo "$gpu_info" | grep -q "NVIDIA";
then
    if echo "$gpu_info" | grep -q "AMD" && [[ -z "${TORCH_COMMAND}" ]]
    then
        export TORCH_COMMAND="pip install torch==2.0.1+rocm5.4.2 torchvision==0.15.2+rocm5.4.2 --index-url https://download.pytorch.org/whl/rocm5.4.2"
    fi
fi

for preq in "${GIT}" "${python_cmd}"
do
    if ! hash "${preq}" &>/dev/null
    then
        printf "\n%s\n" "${delimiter}"
        printf "\e[1m\e[31mERROR: %s is not installed, aborting...\e[0m" "${preq}"
        printf "\n%s\n" "${delimiter}"
        exit 1
    fi
done

if [[ $use_venv -eq 1 ]] && ! "${python_cmd}" -c "import venv" &>/dev/null
then
    printf "\n%s\n" "${delimiter}"
    printf "\e[1m\e[31mERROR: python3-venv is not installed, aborting...\e[0m"
    printf "\n%s\n" "${delimiter}"
    exit 1
fi

cd "${install_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/, aborting...\e[0m" "${install_dir}"; exit 1; }
if [[ -d "${clone_dir}" ]]
then
    cd "${clone_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/%s/, aborting...\e[0m" "${install_dir}" "${clone_dir}"; exit 1; }
else
    printf "\n%s\n" "${delimiter}"
    printf "Clone stable-diffusion-webui"
    printf "\n%s\n" "${delimiter}"
    "${GIT}" clone https://github.com/AUTOMATIC1111/stable-diffusion-webui.git "${clone_dir}"
    cd "${clone_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/%s/, aborting...\e[0m" "${install_dir}" "${clone_dir}"; exit 1; }
fi

if [[ $use_venv -eq 1 ]] && [[ -z "${VIRTUAL_ENV}" ]];
then
    printf "\n%s\n" "${delimiter}"
    printf "Create and activate python venv"
    printf "\n%s\n" "${delimiter}"
    cd "${install_dir}"/"${clone_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/%s/, aborting...\e[0m" "${install_dir}" "${clone_dir}"; exit 1; }
    if [[ ! -d "${venv_dir}" ]]
    then
        "${python_cmd}" -m venv "${venv_dir}"
        first_launch=1
    fi
    # shellcheck source=/dev/null
    if [[ -f "${venv_dir}"/bin/activate ]]
    then
        source "${venv_dir}"/bin/activate
    else
        printf "\n%s\n" "${delimiter}"
        printf "\e[1m\e[31mERROR: Cannot activate python venv, aborting...\e[0m"
        printf "\n%s\n" "${delimiter}"
        exit 1
    fi
else
    printf "\n%s\n" "${delimiter}"
    printf "python venv already activate or run without venv: ${VIRTUAL_ENV}"
    printf "\n%s\n" "${delimiter}"
fi

# Try using TCMalloc on Linux
prepare_tcmalloc() {
    if [[ "${OSTYPE}" == "linux"* ]] && [[ -z "${NO_TCMALLOC}" ]] && [[ -z "${LD_PRELOAD}" ]]; then
        TCMALLOC="$(PATH=/sbin:$PATH ldconfig -p | grep -Po "libtcmalloc(_minimal|)\.so\.\d" | head -n 1)"
        if [[ ! -z "${TCMALLOC}" ]]; then
            echo "Using TCMalloc: ${TCMALLOC}"
            export LD_PRELOAD="${TCMALLOC}"
        else
            printf "\e[1m\e[31mCannot locate TCMalloc (improves CPU memory usage)\e[0m\n"
        fi
    fi
}

KEEP_GOING=1
export SD_WEBUI_RESTART=tmp/restart
while [[ "$KEEP_GOING" -eq "1" ]]; do
    if [[ ! -z "${ACCELERATE}" ]] && [ ${ACCELERATE}="True" ] && [ -x "$(command -v accelerate)" ]; then
        printf "\n%s\n" "${delimiter}"
        printf "Accelerating launch.py..."
        printf "\n%s\n" "${delimiter}"
        prepare_tcmalloc
        accelerate launch --num_cpu_threads_per_process=6 "${LAUNCH_SCRIPT}" "$@"
    else
        printf "\n%s\n" "${delimiter}"
        printf "Launching launch.py..."
        printf "\n%s\n" "${delimiter}"
        prepare_tcmalloc
        "${python_cmd}" -u "${LAUNCH_SCRIPT}" "$@"
    fi

    if [[ ! -f tmp/restart ]]; then
        KEEP_GOING=0
    fi
done

逐行解析

SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )

1. BASH_SOURCE[0]: 这是一个包含当前 Bash 脚本文件名的数组。${BASH_SOURCE[0]} 表示当前脚本的文件名。

2. dirname -- "${BASH_SOURCE[0]}": dirname 命令用于获取文件路径的目录部分。这里它获取了 ${BASH_SOURCE[0]} 即当前脚本的目录部分。

3. cd -- "$( dirname -- "${BASH_SOURCE[0]}" )": 利用 cd 命令进入到当前脚本所在的目录。

4. &> /dev/null: 这部分是将标准输出和标准错误输出都重定向到 /dev/null，即将输出信息丢弃。这样做是为了在 cd 过程中忽略不必要的输出。

5. pwd: 最后，pwd 命令用于获取当前工作目录的绝对路径。这是因为 cd 之后，脚本的工作目录就变成了当前脚本所在的目录。

6. SCRIPT_DIR=$( ... ): 将整个命令的输出（即当前脚本的目录路径）赋值给变量 SCRIPT_DIR。

这一行代码的作用是获取当前 Bash 脚本所在的目录的绝对路径，并将其存储在变量 SCRIPT_DIR 中

 

# If run from macOS, load defaults from webui-macos-env.sh
if [[ "$OSTYPE" == "darwin"* ]]; then
    if [[ -f "$SCRIPT_DIR"/webui-macos-env.sh ]]
        then
        source "$SCRIPT_DIR"/webui-macos-env.sh
    fi
fi

 如果操作系统是darwin,就判断当前目路下的webui-macos-env.sh是否是一个文件，如果是的话就执行它。

# Read variables from webui-user.sh
# shellcheck source=/dev/null
if [[ -f "$SCRIPT_DIR"/webui-user.sh ]]
then
    source "$SCRIPT_DIR"/webui-user.sh
fi

读取用户自定义的变量 ，如果当前目录下的webui-user.sh是一个文件，就执行它

webui-user.sh

#!/bin/bash
#########################################################
# Uncomment and change the variables below to your need:#
#########################################################

# Install directory without trailing slash
#install_dir="/home/$(whoami)"

# Name of the subdirectory
#clone_dir="stable-diffusion-webui"

# Commandline arguments for webui.py, for example: export COMMANDLINE_ARGS="--medvram --opt-split-attention"
#export COMMANDLINE_ARGS=""

# python3 executable
#python_cmd="python3"

# git executable
#export GIT="git"

# python3 venv without trailing slash (defaults to ${install_dir}/${clone_dir}/venv)
#venv_dir="venv"

# script to launch to start the app
#export LAUNCH_SCRIPT="launch.py"

# install command for torch
#export TORCH_COMMAND="pip install torch==1.12.1+cu113 --extra-index-url https://download.pytorch.org/whl/cu113"

# Requirements file to use for stable-diffusion-webui
#export REQS_FILE="requirements_versions.txt"

# Fixed git repos
#export K_DIFFUSION_PACKAGE=""
#export GFPGAN_PACKAGE=""

# Fixed git commits
#export STABLE_DIFFUSION_COMMIT_HASH=""
#export CODEFORMER_COMMIT_HASH=""
#export BLIP_COMMIT_HASH=""

# Uncomment to enable accelerated launch
#export ACCELERATE="True"

# Uncomment to disable TCMalloc
#export NO_TCMALLOC="True"

###########################################

webui-usr.sh中的变量一般不建议修改。

# If $venv_dir is "-", then disable venv support
use_venv=1
if [[ $venv_dir == "-" ]]; then
  use_venv=0
fi

如果venv_dir变量等于-，就不适用venv虚拟环境。