Add hidden email_host field on site.

Use this in case your email domain is different than your web domain.

To change:

> rails console
> Site.current.update_attribute(:email_host, 'emaildomain.com')

app/models/group.rb

@@ -173,7 +173,7 @@ def can_share?(person)
   end
 
   def full_address
-    address.to_s.any? ? (address + '@' + Site.current.host) : nil
+    address.to_s.any? ? (address + '@' + Site.current.email_host) : nil
   end
 
   def get_people_attendance_records_for_date(date)

app/models/message.rb

@@ -147,7 +147,7 @@ def reply_instructions(to_person)
       msg << "Hit \"Reply\" to send a message to #{self.person.name rescue 'the sender'} only.\n"
       if group.can_post? to_person
         if group.address.to_s.any?
-          msg << "Hit \"Reply to All\" to send a message to the group, or send to: #{group.address + '@' + Site.current.host}\n"
+          msg << "Hit \"Reply to All\" to send a message to the group, or send to: #{group.address + '@' + Site.current.email_host}\n"
           msg << "Group page: #{Setting.get(:url, :site)}groups/#{group.id}\n"
         else
           msg << "To reply: #{reply_url}\n"

app/models/notifier.rb

@@ -65,7 +65,7 @@ def full_message(to, msg, id_and_code=nil)
         'List-Archive' => "<#{Setting.get(:url, :site)}groups/#{msg.group.id}>"
       ) unless to.new_record? # allows preview to work
       if msg.group.address.to_s.any? and msg.group.can_post?(msg.person)
-        h.update 'CC' => "\"#{msg.group.name}\" <#{msg.group.address + '@' + Site.current.host}>"
+        h.update 'CC' => "\"#{msg.group.name}\" <#{msg.group.address + '@' + Site.current.email_host}>"
       end
     end
     headers h
@@ -222,7 +222,7 @@ def receive(email)
     sent_to.each do |address|
       address, domain = address.strip.downcase.split('@')
       next unless address.any? and domain.any?
-      our_domain = [Site.current.host, Site.current.secondary_host].compact.include?(domain)
+      our_domain = [Site.current.email_host, Site.current.secondary_host].compact.include?(domain)
       if our_domain and group = Group.where(address: address).first and group.can_send?(@person)
         message = group_email(group, email, body)
         if @message_sent_to_group

app/models/site.rb

@@ -65,8 +65,12 @@ def multisite_host
     end
   end
 
+  def email_host
+    self[:email_host].presence || host
+  end
+
   def noreply_email
-    "noreply@#{self.host}"
+    "noreply@#{self.email_host}"
   end
 
   def visible_name

app/views/groups/_form_features.haml

@@ -5,7 +5,7 @@
   .input-group
     = form.text_field :address, size: 15, class: 'form-control'
     %span.input-group-addon
-      @#{Site.current.host}
+      @#{Site.current.email_host}
   %span.help-block
     = t('groups.edit.address.help')
 .form-group

db/migrate/20140718012829_add_email_host_to_sites.rb

@@ -0,0 +1,7 @@
+class AddEmailHostToSites < ActiveRecord::Migration
+  def change
+    change_table :sites do |t|
+      t.string :email_host
+    end
+  end
+end