Automate with Bash Scripts

This is how I automate using Bash scripts.

Linux is so powerful but sometimes it’s hard to remember some commands.

For example, I use these lines to build and deploy my blog.

$ bundle exec jekyll serve

If everything looks correct then I deploy like this:

$ git add .
$ git commit -m "Awesome commit message here"
$ git push -u origin master
$ JEKYLL_ENV=production jgd

Those are two scripts. One to build and one to deploy.

Instead of keeping scripts in separate files. I wanted to group them all and have an interface where to choose the script.

I automated these tasks:

• Check Memory Usage
• Check Disk Usage
• Build Tom’s blog
• Deploy Tom’s blog
• Launch IntelliJ
• View Tom’s Tasks
• Download Music

Here is how it works:

Creating an interactive menu in bash

I found an awesome article to create an interactive menu in bash here.

Create a master script called menu

$ touch ~/bin/menu
$ chmod u+x ~/bin/menu

The code has these sections:

• Functions to define child scripts
• Define color variables for the menu fonts
• Create a menu (main) function and use case for the menu options
• Call the menu function at the end

At the top of the file, the color variables are set to make the menu more visually appealing.

# Color variables
green='\e[32m'
blue='\e[34m'
red='\e[31m'
clear='\e[0m'

# Color functions
ColorGreen(){
    echo -ne $green$1$clear
}
ColorBlue(){
    echo -ne $blue$1$clear
}

At the bottom of the file the menu (main) function is defined like this example:

menu(){
    echo -ne "
    Automate Tom's Life
    $(ColorGreen '1)') Check Memory
    $(ColorGreen '2)') Check Disk
    $(ColorGreen '3)') Build Blog
    $(ColorGreen '4)') Deploy Blog
    $(ColorGreen '5)') Launch IntelliJ
    $(ColorGreen '6)') View All Tasks
    $(ColorGreen '7)') Download Music
    $(ColorGreen '0)') Exit
    $(ColorBlue 'Choose an option:') "
    read a
    case $a in
        1) check_memory ; menu ;;
        2) check_disk ; menu ;;
        3) build_blog ; menu ;;
        4) deploy_blog ; menu ;;
        5) launch_intelliJ ; menu ;;
        6) view_tasks ; menu ;;
        7) download_music ; menu ;;
        0) exit 0 ;;
        *) echo -e $red"Wrong option."$clear; menu;;
    esac
}

# Call the menu function
menu

Then define the functions after the color functions and before the menu function.

These functions check memory and disk.

function check_memory() {
    free -h
}

function check_disk() {
    df -h
}

I use this function to build my blog.

function build_blog() {
    blogDirectory="/home/tom/blog"

    if [[ "$PWD" == $blogDirectory ]]; then

        echo -n "Build Tom's Blog? [y/n]: "
        read buildBlog

        if [[ $buildBlog == "y" ]]; then
          bundle exec jekyll serve
        else
          echo "Exiting"
        fi
    else
        echo -e $red"Wrong Blog Directory"$clear
    fi
}

I use this to deploy my blog. It also asks the message for the git commit.

function deploy_blog() {
    blogDirectory="/home/tom/blog"

    if [[ "$PWD" == $blogDirectory ]]; then

        echo -n "Deploy Tom's Blog? [y/n]: "
        read buildBlog

        if [[ $buildBlog == "y" ]]; then
          
          git add .
          
          echo -n "Enter commit message: "
          read commitMessage

          git commit -m \""$commitMessage"\"
          git push -u origin master
          JEKYLL_ENV=production jgd

        else
          echo "Exiting"
        fi
    else
        echo -e $red"Wrong Blog Directory"$clear
    fi
}

This is used to launch IntelliJ in the background using the & symbol

function launch_intelliJ() {
    nohup ~/Documents/idea-IU-211.7142.45/bin/idea.sh &
}

This is how I view my todo tasks using the Taskwarrior app

function view_tasks() {
    clear && task simple
}

I am not a fan of streaming music apps because it clogs my memory and disk usage. I have a selected library of songs that I use to focus.

function clean_song() {
    cat *.mp3 > big.mp3
    ffmpeg -i big.mp3 clean.mp3
    echo -ne $green"Rename song to (no spaces or file ext): "$clear
    read song_name
    mv clean.mp3 "$song_name".mp3
    mv "$song_name".mp3 ../
    rm *.mp3
}

function download_music() {
    (
        cd ~/Music/join/
        if [ "$(ls -A)" ]; then
            rm *.mp3
        fi
        echo -ne "Enter URL: "
        read url
        # Example playlist url: https://www.youtube.com/playlist?list=OLAK5uy_nPKXMNuvdxV1NJpPBpr3pd3tQ432eEwmE
        # Example song url: https://www.youtube.com/watch?v=F9edN2tPQVI
        if [[ "$url" =~ playlist ]]; then
            youtube-dl -i -o '%(playlist_index)s.%(ext)s' -x --audio-format mp3 --audio-quality 0 --no-cache-dir "$url"
            clean_song
        elif [[ "$url" =~ watch ]]; then
            youtube-dl -x --audio-format mp3 --audio-quality 0 --no-cache-dir "$url"
            clean_song
        else
            echo "Invalid URL"
        fi
    )
}

Other use cases:

• Automate backing up files
• Send alert notifications to an email
• Manage tasks related to servers