Added tag support.

README.rdoc

@@ -25,9 +25,20 @@ Then
       # ...
     end
 
+    # tagging message for tracking delivery
+
+    class TestMailer < ActionMailer::Base
+      def tagged_message
+        subject    'hello'
+        recipients '[email protected]'
+        from       '[email protected]'
+        tag        'delivery' # Tag should be a single string
+      end
+    end
+
 == Limitations
-  Currently postmark API does not support multiple recipients, or attachments. For more information, check the docs here:
-  TODO: URL to docs.
+  Currently postmark API does not support attachments. For more information, check the docs here:
+  http://developer.postmarkapp.com
 
 == Requirements
 

lib/postmark-rails.rb

@@ -5,12 +5,32 @@ module PostmarkMethods
   def perform_delivery_postmark(message)
     Postmark.send_through_postmark(message)
   end
+
+  def tag(value)
+    @tag = value
+  end
+
+  def self.included(base)
+    base.extend(ClassMethods)
+    base.class_eval do
+      alias_method_chain :create_mail, :tag
+    end
+  end
+
+  def create_mail_with_tag
+    returning create_mail_without_tag do |mail|
+      mail.tag = @tag if @tag
+    end
+  end
+
+  module ClassMethods
+    def postmark_api_key=(value)
+      Postmark.api_key = value
+    end
+  end
+
 end
 
 class ActionMailer::Base
   include PostmarkMethods
-
-  def self.postmark_api_key=(value)
-    Postmark.api_key = value
-  end
 end

spec/fixtures/models/test_mailer.rb

@@ -12,4 +12,11 @@ def multipart_message
     from       '[email protected]'
   end
 
+  def tagged_message
+    subject    'hello'
+    recipients '[email protected]'
+    from       '[email protected]'
+    tag        'delivery'
+  end
+
 end

spec/fixtures/views/test_mailer/tagged_message.erb

@@ -0,0 +1 @@
+test

spec/postmark-rails_spec.rb

@@ -1,11 +1,19 @@
 require File.expand_path(File.dirname(__FILE__) + '/spec_helper')
 
 describe "PostmarkRails" do
+
   it "should use postmark for delivery" do
     Postmark.should_receive(:send_through_postmark) do |message|
       message.subject.should == "hello"
     end
     TestMailer.deliver_simple_message
   end
 
+  it "should allow tagging of message" do
+    Postmark.should_receive(:send_through_postmark) do |message|
+      message.tag.to_s.should == "delivery"
+    end
+    TestMailer.deliver_tagged_message
+  end
+
 end