Mail

Introduction

Mail is an internet library for Ruby that is designed to handle emails generation, parsing and sending in a simple, rubyesque manner.

The purpose of this library is to provide a single point of access to handle all email functions, including sending and receiving emails. All network type actions are done through proxy methods to Net::SMTP, Net::POP3 etc.

Built from my experience with TMail, it is designed to be a pure ruby implementation that makes generating, sending and parsing emails a no brainer.

It is also designed form the ground up to work with Ruby 1.9. This is because Ruby 1.9 handles text encodings much more magically than Ruby 1.8.x and so these features have been taken full advantage of in this library allowing Mail to handle a lot more messages more cleanly than TMail. Mail does run on Ruby 1.8.x… it’s just not as fun to code.

Finally, Mail has been designed with a very simple object oriented system that really opens up the email messages you are parsing, if you know what you are doing, you can fiddle with every last bit of your email directly.

Compatibility

Mail is tested and works on the following platforms:

• ree-1.8.7-2009.10 [ x86_64 ]
• ruby-1.8.6-p383 [ x86_64 ]
• ruby-1.8.7-p248 [ x86_64 ]
• ruby-1.9.1-head [ x86_64 ]
• ruby-1.9.1-p376 [ x86_64 ]

Mail seems to work fine on JRuby as well, however, the Base64 and Quoted-Printable encoding methods are implemented differently and return different values so 6 specs fail. This needs to be triple checked if all OK.

• jruby-1.4.0 [x86_64-java]

Discussion

If you want to discuss mail with like minded individuals, please subscribe to the Google Group groups.google.com/group/mail-ruby

Current Capabilities of Mail

• RFC2822 Support, Reading and Writing
• RFC2045-2049 Support for multipart emails
• Support for creating multipart alternate emails
• Support for reading multipart/report emails & getting details from such
• Support for multibyte emails - needs quite a lot of work and testing
• Wrappers for File, Net/POP3, Net/SMTP

Mail is RFC2822 compliant now, that is, it can parse and generate valid US-ASCII emails. There are a few obsoleted syntax emails that it will have problems with, but it also is quite robust, meaning, if it finds something it doesn’t understand it will not crash, instead, it will skip the problem and keep parsing. In the case of a header it doesn’t understand, it will initialise the header as an optional unstructured field and continue parsing.

This means Mail won’t (ever) crunch your data (I think).

You can also create MIME emails. There are helper methods for making a multipart/alternate email for text/plain and text/html (the most common pair) and you can manually create any other type of MIME email.

Roadmap

Next TODO:

• Improve MIME support for character sets in headers, currently works, mostly, needs refinement.
• Add IMAP wrapper

Testing Policy

Basically… we do BDD on Mail. No method gets written in Mail without a corresponding or covering spec. We expect as a minimum 100% coverage measured by RCov. While this is not perfect by any measure, it is pretty good. Additionally, all functional tests from TMail are to be passing before the gem gets released.

It also means you can be sure Mail will behave correctly.

API Policy

No API removals within a single point release. All removals to be depreciated with warnings for at least one MINOR point release before removal.

Also, all private or protected methods to be declared as such - though this is still I/P.

Installation

Installation is fairly simple, I host mail on gemcutter, so you can just do:

 # gem install mail

if you are on gemcutter, if you aren’t, you can by doing:

 # gem install gemcutter
 # gem tumble
 # gem install mail

Warning though, the above will change your first gem repository to gemcutter, this may or may not be a problem for you.

If you want to install mail manually, you can download the gem from github and do:

 # gem install mail-1.2.1.gem

Encodings

If you didn’t know, handling encodings in Emails is not as straight forward as you would hope.

I have tried to simplify it some:

1. All objects that can render into an email, have an :encoded method. Encoded will return the object as a complete string ready to send in the mail system, that is, it will include the header field and value and CRLF at the end and wrapped as needed.
2. All objects that can render into an email, have a :decoded method. Decoded will return the object’s "value" only as a string. This means it will not include the header fields (like ‘To:’ or ‘Subject:’).
3. By default, calling :to_s on a container object will call it’s encoded method, while :to_s on a field object will call it’s decoded method. So calling :to_s on a Mail object will return the mail, all encoded ready to send, while calling :to_s on the From field or the body will return the decoded value of the object. The header object of Mail is considered a container. If you are in doubt, call :encoded, or :decoded explicitly, this is safer if you are not sure.
4. Structured fields that have parameter values that can be encoded (e.g. Content-Type) will provide decoded parameter values when you call the parameter names as methods against the object.
5. Structured fields that have parameter values that can be encoded (e.g. Content-Type) will provide encoded parameter values when you call the parameter names through the object.parameters[’<parameter_name>’] method call.

Contributing

Please do! Contributing is easy in Mail:

1. Check the Reference RFCs, they are in the References directory, so no excuses.
2. Open a ticket on github, maybe someone else has the problem too
3. Make a fork of my github repository
4. Make a spec driven change to the code base
5. Make sure it works and all specs pass, on Ruby versions 1.8.6, 1.8.7 and 1.9
6. Update the README if needed to reflect your change / addition
7. With all specs passing push your changes back to your fork
8. Send me a pull request

Usage

All major mail functions should be able to happen from the Mail::module. So, you should be able to just "require ‘mail’" to get started.

Making an email

 require 'mail'

 mail = Mail.new do
      from 'mikel@test.lindsaar.net'
        to 'you@test.lindsaar.net'
   subject 'This is a test email'
      body File.read('body.txt')
 end

 mail.to_s #=> "From: mikel@test.lindsaar.net\r\nTo: you@...

Making an email, have it your way:

 require 'mail'

 mail = Mail.new do
   body File.read('body.txt')
 end

 mail['from'] = 'mikel@test.lindsaar.net'
 mail[:to]    = 'you@test.lindsaar.net'
 mail.subject = 'This is a test email'

 mail.to_s #=> "From: mikel@test.lindsaar.net\r\nTo: you@...

Don’t Worry About Message IDs:

 require 'mail'

 mail = Mail.new do
     to 'you@test.lindsaar.net'
   body 'Some simple body'
 end

 mail.to_s =~ /Message\-ID: <[\d\w_]+@.+.mail/ #=> 27

Mail will automatically add a Message-ID field if it is missing and give it a unique, random Message-ID along the lines of:

 <4a7ff76d7016_13a81ab802e1@local.fqdn.mail>

Or do worry about Message-IDs:

 require 'mail'

 mail = Mail.new do
          to 'you@test.lindsaar.net'
  message_id '<ThisIsMyMessageId@some.domain.com>'
        body 'Some simple body'
 end

 mail.to_s =~ /Message\-ID: <ThisIsMyMessageId@some.domain.com>/ #=> 27

Mail will take the message_id you assign to it trusting that you know what you are doing.

Sending an email:

Mail defaults to sending via SMTP to local host port 25. If you have a sendmail or postfix daemon running on on this port, sending email is as easy as:

 Mail.deliver do
       from 'me@test.lindsaar.net'
         to 'you@test.lindsaar.net'
    subject 'Here is the image you wanted'
       body File.read('body.txt')
   add_file '/full/path/to/somefile.png'
 end

or

 mail = Mail.new do
       from 'me@test.lindsaar.net'
         to 'you@test.lindsaar.net'
    subject 'Here is the image you wanted'
       body File.read('body.txt')
   add_file {:filename => 'somefile.png', :content => File.read('/somefile.png')}
 end

 mail.deliver!

Sending via sendmail can be done like so:

  mail = Mail.new do
        from 'me@test.lindsaar.net'
          to 'you@test.lindsaar.net'
     subject 'Here is the image you wanted'
        body File.read('body.txt')
    add_file {:filename => 'somefile.png', :content => File.read('/somefile.png')}
  end

  mail.delivery_method :sendmail

  mail.deliver

mail.deliver!

Getting emails from a pop server:

The most recent email:

 require 'mail'

 Mail.defaults do
   pop3 'mail.myhost.com.au', 110 do
     user 'mikel'
     pass 'mypass'
   end
 end

 emails = Mail.last do |email|
   email.reply!("I'll be back on Monday, please be patient!") # +reply!+ still not implemented ^^
 end

The 3 oldest emails sorted by date in descendent order:

 require 'mail'

 Mail.defaults do
   pop3 'mail.myhost.co.jp', 995 do
     user 'mikel'
     pass 'mypass'
     enable_tls
   end
 end

 emails = Mail.first(:count => 3, :order => :desc) do |email|
   email.date
 end

Or even all emails:

 require 'mail'

 Mail.defaults do
   pop3 'mail.myhost.com.au' do
     user 'mikel'
     pass 'mypass'
   end
 end

 emails = Mail.all

 emails.length #=> 12

Reading an Email

 require 'mail'

 mail = Mail.read('/path/to/message.eml')

 mail.envelope.from   #=> 'mikel@test.lindsaar.net'
 mail.from.addresses  #=> ['mikel@test.lindsaar.net', 'ada@test.lindsaar.net']
 mail.sender.address  #=> 'mikel@test.lindsaar.net'
 mail.to              #=> 'bob@test.lindsaar.net'
 mail.cc              #=> 'sam@test.lindsaar.net'
 mail.subject         #=> "This is the subject"
 mail.date.to_s       #=> '21 Nov 1997 09:55:06 -0600'
 mail.message_id      #=> '<4D6AA7EB.6490534@xxx.xxx>'
 mail.body.decoded    #=> 'This is the body of the email...

Many more methods available.

Reading a Multipart Email

 require 'mail'

 mail = Mail.read('multipart_email')

 mail.multipart?          #=> true
 mail.parts.length        #=> 2
 mail.preamble            #=> "Text before the first part"
 mail.epilogue            #=> "Text after the last part"
 mail.parts.map { |p| p.content_type }  #=> ['text/plain', 'application/pdf']
 mail.parts.map { |p| p.class }         #=> [Mail::Message, Mail::Message]
 mail.parts[0].content_type_parameters  #=> {'charset' => 'ISO-8859-1'}
 mail.parts[1].content_type_parameters  #=> {'name' => 'my.pdf'}

Mail generates a tree of parts. Each message has many or no parts. Each part is another message which can have many or no parts.

A message will only have parts if it is a multipart/mixed or related/mixed content type and has a boundary defined.

Writing and sending a multipart/alternative (html and text) email

Mail makes some basic assumptions and makes doing the common thing as simple as possible.… (asking a lot from a mail library)

 require 'mail'

 mail = Mail.deliver do
   to 'nicolas@test.lindsaar.net.au'
   from 'Mikel Lindsaar <mikel@test.lindsaar.net.au>'
   subject 'First multipart email sent with Mail'
   text_part do
     body 'This is plain text'
   end
   html_part do
     content_type 'text/html; charset=UTF-8'
     body '<h1>This is HTML</h1>'
   end
 end

Mail then delivers the email at the end of the block and returns the resulting Mail::Message object, which you can then inspect if you so desire…

 puts mail.to_s #=>

 To: nicolas@test.lindsaar.net.au
 From: Mikel Lindsaar <mikel@test.lindsaar.net.au>
 Subject: First multipart email sent with Mail
 Content-Type: multipart/alternative;
   boundary=--==_mimepart_4a914f0c911be_6f0f1ab8026659
 Message-ID: <4a914f12ac7e_6f0f1ab80267d1@baci.local.mail>
 Date: Mon, 24 Aug 2009 00:15:46 +1000
 Mime-Version: 1.0
 Content-Transfer-Encoding: 7bit

 ----==_mimepart_4a914f0c911be_6f0f1ab8026659
 Content-ID: <4a914f12c8c4_6f0f1ab80268d6@baci.local.mail>
 Date: Mon, 24 Aug 2009 00:15:46 +1000
 Mime-Version: 1.0
 Content-Type: text/plain
 Content-Transfer-Encoding: 7bit

 This is plain text
 ----==_mimepart_4a914f0c911be_6f0f1ab8026659
 Content-Type: text/html; charset=UTF-8
 Content-ID: <4a914f12cf86_6f0f1ab802692c@baci.local.mail>
 Date: Mon, 24 Aug 2009 00:15:46 +1000
 Mime-Version: 1.0
 Content-Transfer-Encoding: 7bit

 <h1>This is HTML</h1>
 ----==_mimepart_4a914f0c911be_6f0f1ab8026659--

Mail inserts the content transfer encoding, the mime version, the content-id’s and handles the content-type and boundary.

Mail assumes that if your text in the body is only us-ascii, that your transfer encoding is 7bit and it is text/plain. You can override this by explicitly declaring it.

Making Multipart/Alternate, without a block

You don’t have to use a block with the text and html part included, you can just do it declaratively. However, you need to add Mail::Parts to an email, not Mail::Messages.

 require 'mail'

 mail = Mail.new do
   to 'nicolas@test.lindsaar.net.au'
   from 'Mikel Lindsaar <mikel@test.lindsaar.net.au>'
   subject 'First multipart email sent with Mail'
 end

 text_part = Mail::Part.new do
   body 'This is plain text'
 end

 html_part = Mail::Part.new do
   content_type 'text/html; charset=UTF-8'
   body '<h1>This is HTML</h1>'
 end

 mail.text_part = text_part
 mail.html_part = html_part

Results in the same email as done using the block form

Getting error reports from an email:

 require 'mail'

 @mail = Mail.read('/path/to/bounce_message.eml')

 @mail.bounced?         #=> true
 @mail.final_recipient  #=> rfc822;mikel@dont.exist.com
 @mail.action           #=> failed
 @mail.error_status     #=> 5.5.0
 @mail.diagnostic_code  #=> smtp;550 Requested action not taken: mailbox unavailable
 @mail.retryable?       #=> false

Attaching and Detaching Files

  require 'mail'

You can just read the file off an absolute path, Mail will try to guess the mime_type and will encode the file in Base64 for you.

  @mail = Mail.new
  @mail.add_file("/path/to/file.jpg")
  @mail.parts.first.attachment? #=> true
  @mail.parts.first.content_transfer_encoding.to_s #=> 'base64'
  @mail.attachments.first.mime_type #=> 'image/jpg'
  @mail.attachments.first.filename #=> 'file.jpg'
  @mail.attachments.first.decoded == File.read('/path/to/file.jpg') #=> true

Or You can pass in file_data and give it a filename, again, mail will try and guess the mime_type for you.

  @mail = Mail.new
  @mail.attachments['myfile.pdf'] = File.read('path/to/myfile.pdf')
  @mail.parts.first.attachment? #=> true
  @mail.attachments.first.mime_type #=> 'application/pdf'
  @mail.attachments.first.decoded == File.read('path/to/myfile.pdf') #=> true

You can also override the guessed mime type if you really know better than mail (this should be rarely needed)

  @mail = Mail.new
  file_data = File.read('path/to/myfile.pdf')
  @mail.attachments['myfile.pdf'] = { :mime_type => 'application/x-pdf',
                                      :content => File.read('path/to/myfile.pdf') }
  @mail.parts.first.mime_type #=> 'application/x-pdf'

Of course… Mail will round trip an attachment as well

  @mail = Mail.new do
    to 'nicolas@test.lindsaar.net.au'
    from 'Mikel Lindsaar <mikel@test.lindsaar.net.au>'
    subject 'First multipart email sent with Mail'
    text_part do
      body 'Here is the attachment you wanted'
    end
    html_part do
      content_type 'text/html; charset=UTF-8'
      body '<h1>Funky Title</h1><p>Here is the attachment you wanted</p>'
    end
    add_file '/path/to/myfile.pdf'
  end

  @round_tripped_mail = Mail.new(@mail.encoded)

  @round_tripped_mail.attachments.length #=> 1
  @round_tripped_mail.attachments.first.filename #=> 'myfile.pdf'

Using Mail with Testing or Spec’ing Libraries

If mail is part of your system, you’ll need a way to test it without actually sending emails, the TestMailer can do this for you.

  require 'mail'
  => true
  Mail.defaults do
    delivery_method :test
  end
  => #<Mail::Configuration:0x19345a8 @delivery_method=Mail::TestMailer>
  Mail.deliveries
  => []
  Mail.deliver do
    to 'mikel@me.com'
    from 'you@you.com'
    subject 'testing'
    body 'hello'
  end
  => #<Mail::Message:0x19284ec ...
  Mail.deliveries.length
  => 1
  Mail.deliveries.first
  => #<Mail::Message:0x19284ec ...
  Mail.deliveries.clear
  => []

Excerpts from TREC Spam Corpus 2005

The spec fixture files in spec/fixtures/emails/from_trec_2005 are from the 2005 TREC Public Spam Corpus. They remain copyrighted under the terms of that project and license agreement. They are used in this project to verify and describe the development of this email parser implementation.

plg.uwaterloo.ca/~gvcormac/treccorpus/

They are used as allowed by ‘Permitted Uses, Clause 3’:

    "Small excerpts of the information may be displayed to others
     or published in a scientific or technical context, solely for
     the purpose of describing the research and development and
     related issues."

     -- http://plg.uwaterloo.ca/~gvcormac/treccorpus/

License:

(The MIT License)

Copyright © 2009

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ‘Software’), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.