Home/ Questions/Q 7886789
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-03T05:24:34+00:00

Sample hash: { audio => { audio/aac => [aac], audio/mpeg => [mp3, mp2], audio/mp4

  • 0

Sample hash:

  {
    "audio" =>  {
      "audio/aac" => ["aac"],
      "audio/mpeg" => ["mp3", "mp2"],
      "audio/mp4" => ["m4a", "m4b", "m4r", "3gp"],
      "audio/ogg" => ["ogg", "oga"],
      "audio/flac" => ["flac"],
      "audio/speex" => ["spx"],
      "audio/x-ms-wma" => ["wma"],
      "audio/x-pn-realaudio" => ["rm", "ram"],
      "audio/vnd.wave" => ["wav"],
      "audio/x-musepack" => ["mpc", "mp+", "mpp"],
      "audio/x-aiff" => ["aiff", "aif", "aifc"],
      "audio/x-tta" => ["tta"]
    },
    "video" =>  {
      "video/mp4" => ["mp4"],
      "video/mpeg" => ["mpg", "mpeg"],
      "video/x-m4v" => ["m4v"],
      "video/quicktime" => ["mov"],
      "video/x-msvideo" => ["avi"],
      "video/x-flv" => ["flv"],
      "video/webm" => ["webm"]
    }
  }

What’s the best way given a file extension to get the associated content type (first match is okay)?

Searching for “flac” should return “audio/flac”.

Currently I’m using this:

hsh.each_key do |group|
  hsh[group].each do |k,v|
    return k if v.include?(extension)
  end
end
Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Unraveling that sort of structure is best done when it’s created. But, you can loop through the various levels and get something useful from it. If I assign your initial hash to mime_hash I can unravel it using:

    Hash[*mime_hash.map{ |av, types| types.map{ |mime_type, extensions| extensions.product([mime_type]) } }.flatten]

    or more verbosely:

    Hash[
  *mime_hash.map{ |av, types| 
    types.map{ |mime_type, extensions| 
      extensions.product([mime_type]) 
    } 
  }.flatten
]

    Which will return:

    {
     "aac" => "audio/aac",
     "mp3" => "audio/mpeg",
     "mp2" => "audio/mpeg",
     "m4a" => "audio/mp4",
     "m4b" => "audio/mp4",
     "m4r" => "audio/mp4",
     "3gp" => "audio/mp4",
     "ogg" => "audio/ogg",
     "oga" => "audio/ogg",
    "flac" => "audio/flac",
     "spx" => "audio/speex",
     "wma" => "audio/x-ms-wma",
      "rm" => "audio/x-pn-realaudio",
     "ram" => "audio/x-pn-realaudio",
     "wav" => "audio/vnd.wave",
     "mpc" => "audio/x-musepack",
     "mp+" => "audio/x-musepack",
     "mpp" => "audio/x-musepack",
    "aiff" => "audio/x-aiff",
     "aif" => "audio/x-aiff",
    "aifc" => "audio/x-aiff",
     "tta" => "audio/x-tta",
     "mp4" => "video/mp4",
     "mpg" => "video/mpeg",
    "mpeg" => "video/mpeg",
     "m4v" => "video/x-m4v",
     "mov" => "video/quicktime",
     "avi" => "video/x-msvideo",
     "flv" => "video/x-flv",
    "webm" => "video/webm"
}
    • 0