Download an egghead.io lesson using youtube-dl

dl-lesson.sh

#!/bin/bash
# Usage: dl-lession.sh https://egghead.io/courses/react-fundamentals

let n=1
for link in $(curl -s $1 | pup '.series-lessons-list a attr{href}'); do
  filename=$(echo $link | sed "s/https:\/\/egghead.io\/lessons\///g" | sed "s/\?.*$//g")
  filename_numbered=$(echo "$n $filename" | awk '{ printf "%02i-%s.mp4\n", $1, $2 }')
  youtube-dl -o "$filename_numbered" "$link"
  let n++
done