Question

我对SHELL脚本非常新鲜。我想知道是否有人可以解释我，我怎样才能将用户改为欲望组。我想要的是什么脚本是这样的：

$ ./sample_script

这将检查/etc/passwd并列出像这样的用户名

1. user1 
2. user2 
3. user3
4. user4

然后：

Enter the username : 1

然后，脚本会询问

What do you want to do (Deny or Grant)? : deny

如果用户选择user1或user2，脚本将使用 sudo usermod -G DENY_GROUP USER_NAME或 sudo usermod -G ACCESS_GROUP USER_NAME和像这样打印输出：

"User1 is successfully denied or granted"

如果用户选择user3或user4，脚本将按如下方式打印输出：

"You don't have a permission to deny the user3 or user4. Please contact your
administrator."

Answer 1

以下内容可以帮助您入门。

我发现这些是有用的参考资料：

Advanced Bash-Scripting Guide

Shell Style Guide

我的答案格式大量借鉴了谷歌外壳风格指南。

#!/bin/bash

CHOSEN_USER=""
CHOSEN_USER_NAME=""
CHOSEN_PERMISSION=""
CHOSEN_GROUP=""

# Constants
readonly SUCCESS_EXIT=0
readonly ERROR_EXIT=64
readonly PASSWORD_FILE=/etc/passwd
readonly DENY_INPUT="Deny"
readonly GRANT_INPUT="Grant"
readonly DENY_GROUP="DENY_GROUP"
readonly ACCESS_GROUP="ACCESS_GROUP"
readonly PERMISSION_LIST="user1,user2"
readonly SUCCESS_MESSAGE="is successfully denied or granted"
readonly FAIL_MESSAGE="was not successfully denied or granted"

function write_error_message() {
    echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $@" >&2
}

function write_progress_message() {
    if [[ "${VERBOSE}" = "true" ]]; then
        echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $@" >&1
    fi
}

function display_users() {
    awk -F':' '{ print NR ". " $1; }' $PASSWORD_FILE
}

function get_user() {
    read -p "Enter the username : " CHOSEN_USER

    write_progress_message "Selected user number: $CHOSEN_USER"
}

function get_chosen_user_name() {
    CHOSEN_USER_NAME=`awk -F':' -v user_num="${CHOSEN_USER}" '{ if (NR == user_num) print $1; }' $PASSWORD_FILE`
}

function check_can_set_user_name() {
    echo "${PERMISSION_LIST}" | grep -q "$CHOSEN_USER_NAME"

    if [[ $? -ne 0 ]]; then
        local FAIL_MESSAGE
        PERM_FAIL_MESSAGE="You don't have a permission to deny the user ${CHOSEN_USER_NAME}. Please contact your administrator."
        write_error_message  "${PERM_FAIL_MESSAGE}"
        exit "${ERROR_EXIT}"
    fi
}

function get_group_permission() {
    read -p "What do you want to do (Deny or Grant)? : " CHOSEN_PERMISSION

    if [[ "${CHOSEN_PERMISSION}" =  "${DENY_INPUT}" ]] || [[ "${CHOSEN_PERMISSION}" =  "${GRANT_INPUT}" ]]; then
        if [[ "${CHOSEN_PERMISSION}" = "${DENY_INPUT}" ]]; then
            CHOSEN_GROUP="${DENY_GROUP}"
        else
            CHOSEN_GROUP="${ACCESS_GROUP}"
        fi
    else
        get_group_permission
    fi

    write_progress_message "Selected permission: $CHOSEN_PERMISSION"
}
function set_group_permission() {
    local command
    command="sudo usermod -G ${CHOSEN_GROUP} ${CHOSEN_USER_NAME}"

    eval "${command}"

    if [[ $? -eq 0 ]]; then
        echo "${CHOSEN_USER_NAME} ${SUCCESS_MESSAGE}"
    else
        write_error_message "${CHOSEN_USER_NAME} ${FAIL_MESSAGE}"
        exit "${ERROR_EXIT}"
    fi
}

function print_usage() {
    echo "NAME"
    echo "     add_user_to_group.sh - Add user to group"
    echo
    echo "SYNOPSIS"
    echo "     add_user_to_group.sh [OPTIONS]"
    echo
    echo "DESCRIPTION"
    echo "     Display list of users and allow operator to add one to a group"
    echo
    echo "OPTIONS"
    echo "     -v Explain what is being done"
    echo "     -u display a help message and exit"
}

function main() {
    VERBOSE="false"

    # read arguments
    while getopts "vu" flag; do
        case "${flag}" in
            v) VERBOSE="true" ;;
            u) print_usage
               exit "${SUCCESS_EXIT}" ;;
            *) exit "${ERROR_EXIT}" ;;
        esac
    done

    readonly VERBOSE

    display_users
    get_user
    get_chosen_user_name
    check_can_set_user_name
    get_group_permission
    set_group_permission

    exit ${SUCCESS_EXIT}
}

main "$@"

如何为usermod创建shell脚本

1 个答案: