Create a tar file with all of the missing package files

dpkgtar.rb

#!/usr/bin/env ruby
require 'open3'

## To Use
## mkdir /tmp/dpkgtar
## cd /tmp/dpkgtar
## docker run -w /dpkgtar -v /tmp/dpkgtar:/dpkgtar -it cloudfoundry/cflinuxfs2 bash
## curl https://gist.githubusercontent.com/dgodd/53ae83b5894d4241b9af26eec0db805f/raw/e00e7ee66281578ed49d84464614b4b298cb02f0/dpkgtar.rb -o /dpkgtar/dpkgtar.rb
## ruby ./dpkgtar.rb [PACKAGES] ## eg. ghostscript libcupsfilters1 libcupsimage2 libgs9 libgs9-common libijs-0.35 libjbig2dec0 libpaper-utils libpaper1 poppler-data
##
## Then copy dpkgfiles.tgz to your app, and make extracting it the first thing the start command does. 


packages = ARGV

_, status = Open3.capture2(*(%w(apt-get update)))
raise "Could not update packages" unless status.success?
_, status = Open3.capture2(*(%w(apt-get -fy install) + packages))
raise "Could not install packages" unless status.success?

files, status = Open3.capture2('dpkg-query', '-L', *packages)
raise "Could not find files" unless status.success?
files = files.split(/\n/)
files = files.reject{ |n| n =~ %r{/doc/} || n =~ %r{/man/} }
files = files.select { |n| File.file?(n) }

# files.sort.each { |n| puts n }

files, status = Open3.capture2('tar', '-zcf', 'dpkgfiles.tgz', *files)
raise "Could not tar files" unless status.success?