IMAP (Ruby) : Fail to fetch/save audio (.wav) attachment in correct format

Question

I am using IMAP apis to access my mailbox and download attachments (.wav audio file) if any. After saving the attachment, I expect it to be a valid .wav file which I could play, but it gives me invalid file.

When I save the attachment after decoding (mail.attachments.first.decoded), it has the following contents:

  X-MCPBodyContent: --- 
  duration: 5
  internal_codec: alaw
  external_codec: wav
  type: 1
  filename: /9/04/04/04/05/m_88888_56b07809-1fe6-4cf7-8328-8e9bb0bd7716
  $$$$$

If I save the attachment as it is (mail.attachments.first), it has the following:

  Date: Tue, 18 Oct 2011 09:06:07 -0400
  Mime-Version: 1.0
  Content-Type: audio/wav;
    charset=UTF-8
  Content-Transfer-Encoding: base64
  Content-Disposition: attachment;
   filename=m_88888_56b07809-1fe6-4cf7-8328-8e9bb0bd7716.wav
  Content-ID: <4e9d79bfa830f_7efc3f9579013bfc3648e@vavcafeserver2.mail>

  WC1NQ1BCb2R5Q29udGVudDogLS0tIApkdXJhdGlvbjogNQppbnRlcm5hbF9j
  b2RlYzogYWxhdwpleHRlcm5hbF9jb2RlYzogd2F2CnR5cGU6IDEKZmlsZW5h
  bWU6IC85LzA0LzA0LzA0LzA1L21fODg4ODhfNTZiMDc4MDktMWZlNi00Y2Y3
  LTgzMjgtOGU5YmIwYmQ3NzE2CiQkJCQk

Here is the code snippet:

require 'net/imap'
imap = Net::IMAP.new('the_url', 143, false, nil, false) 
imap.login('username', 'password') 
imap.select('Inbox') 
# All msgs in a folder 
msgs = imap.uid_search(["ALL"]) 

# Read each message 
msgs.each do |uid| 
  _body = imap.uid_fetch(uid, "RFC822")[0].attr["RFC822"]

  require 'mail'
  mail = Mail.new(_body)

  attachment = mail.attachments.first
  fn = attachment.filename
  begin
    File.open( fn, "w+b", 0644 ) { |f| f.write attachment.decoded}
  rescue Exception => e
    puts "Error : Unable to save data for #{fn} because #{e.message}"
  end
end  
imap.logout

Please let me know how to get the attachment in correct format.

Any help would highly be appreciated.

Thanks

score 2 · Answer 1 · answered Jan 22 '13 at 10:31

2

Following works for me - tested with mp3, jpg and pdf files.

new_mail = imap.search(["ALL"]).each do |uid|
  body = imap.fetch(uid, "BODY[]")[0].attr["BODY[]"]
  mail = Mail.new(body)
  mail.attachments.each do |a|
      File.open("/home/vknoll/Downloads/imap/#{a.filename}", 'wb') do |file|
        file.write(a.body.decoded)
      end
  end
end

answered Jan 22 '13 at 10:31

Hugo Stieglitz

55
3

What Mail class did you use? Did you use the mail gem for that? – Abdo Jan 22 '14 at 12:41

score 0 · Answer 2 · answered Feb 16 '12 at 18:13

0

I haven't tried it, but is it worth closing the file in an ensure block? It may well be that this is required to flush the stream out to disk.

answered Feb 16 '12 at 18:13

hcarver

7,126
4
41
67

2

The File.open block automatically closes the file for you. http://stackoverflow.com/a/4795782/226255 – Abdo Jan 22 '14 at 12:47

IMAP (Ruby) : Fail to fetch/save audio (.wav) attachment in correct format

2 Answers2