tyt/README.org

• tyt
  • Script
    • Dependencies
    • Usage
    • Arguments
    • Greeter
    • Get URL
    • Play video

tyt

Terminal YouTube (tyt) is a small bash script that lets you play YouTube videos by query from the command line. It is created via literate programming, you can find the code below.

Script

Dependencies

The dependencies of the script are:

• jq
• mpv
• youtube-dl

Please make sure those are available on your system. If you are using the Nix package manager, you can run nix-shell in the project directory. This will drop you into a shell with all requirements fulfilled.

On the start of the script, it is checked if the dependencies are fulfilled.

  if ! command -v mpv &> /dev/null
  then
    echo -ne "\e[1mmpv\e[0m was not found, please install it"
exit 1
  elif ! command -v youtube-dl &> /dev/null
  then
    echo -ne "\e[1myoutube-dl\e[0m was not found, please install it"
exit 1
  fi

Usage

This function prints the usage of the script.

  function print_usage {
    echo "tyt [ -a* | --alternative ] \"QUERY\""
  }

Arguments

At first we parse the arguments. We have the following flags:

a*|alternative

Alternative video (optional); You can parse any amount of alternatives (e.g. -aaa)

Additionally we have exacly one mandatory quoted string as query.

  alternative=0
  format="flac"
  help=false

  for arg in "$@"
  do
    case $arg in
      -a*)
        alternative="${arg:1}"
        alternative="${#alternative}"
        shift
        ;;
      --alternative)
        alternative=1
        shift
        ;;
      -h|--help)
        help=true
        shift
        ;;
      ,*)
        other_arguments+=("$1")
        shift
        ;;
    esac
  done

  if [ "$help" = true ]
  then
    print_usage
    exit 0
  fi

  if [ "${#other_arguments[@]}" != "1" ]
  then
    print_usage
    exit 1
  fi

  query="${other_arguments[0]}"

Greeter

If the arguments match, print a greeter.

  echo -ne "\n    \e[1m  \ /\e[0m\n"
  echo -ne "    \e[1m=======\e[0m\n"
  echo -ne "    | \e[31m\e[1mtyt\e[0m |\n"
  echo -ne "    \e[1m=======\e[0m\n\n"

Get URL

To play a video, we need to get a valid URL. Since there are sometimes parsing errors of the JSON response, we use an endless loop to try until we get a valid response. The first n URLs are saved if an alternative download is requested.

  i=0
  n=$((alternative+1))

  echo -ne "Searching for: \e[33m\e[1m$query\e[0m    \r"

  until results=$(youtube-dl --default-search "ytsearch" -j "ytsearch$n:$query") &> /dev/null
  do

    case $i in
      0)
	appendix="   "
	;;
      1)
	appendix=".  "
	;;
      2)
	appendix=".. "
	;;
      ,*)
	appendix="..."
	;;
    esac

    echo -ne "Searching for: \e[33m\e[1m$query\e[0m $appendix\r"

    i=$(((i + 1) % 4))
    sleep 1

  done

  echo -ne "Searching for: \e[33m\e[1m$query\e[0m    \n"

  urls=$(echo $results | jq '.webpage_url' | tr -d '"')

  OLDIFS=$IFS
  IFS=$'\n'
  results=($results)
  urls=($urls)
  IFS=$OLDIFS

  result=${results[$alternative]}
  url=${urls[$alternative]}

Play video

Finally the video is played via mpv.

  i=0  

  title=$(echo $result | jq '.fulltitle')
  title="${title%\"}"
  title="${title#\"}"

  echo -ne "Playing: \e[32m\e[1m$title\e[0m"

  mpv $url &> /dev/null