calibre persist metadata in pdf

calibre_meta

#!/usr/bin/env ruby

files = Dir.glob(ENV['HOME'] + "/Calibre Library/**/*.pdf")
# meta = Dir.glob(ENV['HOME'] + "/Calibre Library/**/metadata.opf")
  
dirs = []

for file in files
  dirs << [ File.dirname(file), File.basename(file) ]
end

for dir in dirs
  Dir.chdir(dir[0]) {
    # `ebook-meta --from-opf=metadata.opf `
    system('ebook-meta', '--from-opf=metadata.opf', dir[1])
  }
end