youtube video download

Timestamp: 2011-05-26 10:29
Tags: code

Being intimidated by youtube-dl with its over 3000 lines of code, I thought there must be a simpler way than that and wrote a little shell script that now does all I want: download youtube videos.

#!/bin/sh -e

if [ "$#" -ne "1" ]; then
  echo specify the youtube id as the first argument
  exit 1
fi

code="$1"

urldecode() { echo -n $1 | sed 's/%\([0-9A-F]\{2\}\)/\\\\\\\x\1/gI' | xargs printf; }

cookiejar=`mktemp`
baseurl="http://www.youtube.com/get_video_info?video_id=$code&el=detailpage"
data=`curl --silent --cookie-jar "$cookiejar" "$baseurl"`

highestfmt=0
highesturl=""
title=""
for part in `echo $data | tr '&' ' '`; do
  key=`echo $part | cut -d"=" -f1`
  value=`echo $part | cut -d"=" -f2`
  if [ "$value" != "" ]; then
    value=`urldecode "$value"`
  fi    
  case "$key" in
  "fmt_url_map") 
    for format in `echo $value | tr ',' ' '`; do
      fmt=`echo $format | cut -d"|" -f1`
      url=`echo $format | cut -d"|" -f2`
      if [ "$fmt" = "18" ] \
      || [ "$fmt" = "22" ] \
      || [ "$fmt" = "37" ] \
      || [ "$fmt" = "43" ] \
      || [ "$fmt" = "45" ] ; then
        if [ "$fmt" -gt "$highestfmt" ]; then
          highestfmt=$fmt
          highesturl=$url
        fi
      fi
    done ;;
  "title") title="$value" ;;
  esac
done

echo writing output to "${title}_${code}.mp4"
curl --location --cookie "$cookiejar" "$highesturl" > "${title}_${code}.mp4"
rm $cookiejar

and in python because that was so much fun

#!/usr/bin/env python

import cookielib, urllib2, shutil, urlparse, sys

cookie_processor = urllib2.HTTPCookieProcessor(cookielib.CookieJar())
urllib2.install_opener(urllib2.build_opener(cookie_processor))

if len(sys.argv) != 2:
    print "specify the youtube id as the first argument"
    exit(1)

code = sys.argv[1]
baseurl = "http://www.youtube.com/get_video_info?video_id=%s&el=detailpage"%code
data = urllib2.urlopen(baseurl).read()

data = urlparse.parse_qs(data)
title = data["title"][0]
url = dict(part.split('|', 1) for part in data["fmt_url_map"][0].split(','))
url = url.get("37", url.get("22", url.get("18")))

print "writing output to %s_%s.mp4"%(title,code)
data = urllib2.urlopen(url)
with open("%s_%s.mp4"%(title,code), 'wb') as fp:
    shutil.copyfileobj(data, fp, 16*1024)

The shell script can also easily turned into something that will deliver you the video remotely. This is useful if you have the server in the US and get annoyed by all the “This video contains content from ****. It is not available in your country.” messages when accessing content e.g. from Germany.

Just change the top part into this:

#!/bin/sh -e

read request

while /bin/true; do
  read header
  [ "$header" = "`printf '\r'`" ] && break
done

code="${request#GET /}"
code="${code% HTTP/*}"

and the bottom part into this:

url=`curl --silent --head --output /dev/null --write-out %{redirect_url} --cookie "$cookiejar" "$highesturl"`
while [ "$url" != "" ]; do
        highesturl=$url
	url=`curl --silent --head --output /dev/null --write-out %{redirect_url} --cookie "$cookiejar" "$highesturl"`
done
curl --silent --include --cookie "$cookiejar" "$highesturl"
rm $cookiejar

then you can run the script like this:

while true; do netcat -l -p 80 -e youtube.sh; done

or by using inetd:

www stream tcp nowait nobody /usr/local/bin/youtube youtube

And better chroot the whole thing.