ActionMailer works with only one smtp account; a single google apps account is limited to 500 (or 2000) mails per day; my app legitimately needs more. Besides, I'd rather notifications come from an appropriately named account rather than a generic "no-reply@example.com" address. Here's what I came up with. Firstly, config/smtp.yml describes my various accounts - I settled on one per mailer class. Secondly, a patch to ActionMailer::Base enables switching smtp accounts based on the mailer class.
Here's an example with four mailers: an account mailer, an exception notifier (works with the lovely ExceptionNotifier plugin), a "share this" mailer so your site can be all viral and stuff, and a prize mailer for the good news.
config/smtp.yml
defaults: &defaults address: smtp.gmail.com port: 587 domain: example.com authentication: !ruby/sym plain account_mailer: <<: *defaults user_name: accounts@example.com password: "pw1" prize_mailer: <<: *defaults user_name: winner@example.com password: "pw2" exception_notifier: <<: *defaults user_name: dev_team_obviously_sucks@example.com password: "pw3" share_this_mailer: <<: *defaults user_name: share_this@example.com password: "pw4"
ActionMailer::Base patch
require 'smtp_tls'
module ActionMailer
class Base
cattr_accessor :smtp_config
self.smtp_config = YAML::load(File.open("#{RAILS_ROOT}/config/smtp.yml"))
def smtp_settings
smtp_config[mailer_name].symbolize_keys
end
end
end
I put this in config/initializers/action_mailer.rb.
And that's it!
No changes required to your mailers or email templates or anything else in your application.
As you can see, the patch merely overrides ActionMailer's smtp_settings class method
and replaces it with an instance method that decides at sending-time which smtp configuration to use.
We needed to do this because sendmail was failing erratically - some users weren't getting any mail from our app at all - presumably due to hypersensitive spam filters somewhere on the chain, maybe related to my not understanding how SPF records are supposed to work.
You could easily fancify this to switch SMTP config based on the time of day,
or based on your user's locale
(so you can use a nicely localised "from" address - Google overrides the "from" address sent by ActionMailer),
or even based on whether the Moon is in Scorpio if you cared.
Just replace the call to mailer_name with a call to your config-switching method.
I understand that rails 3 is beautifuller in many ways including the way ActionMailer works so this might well be obsolete in a few months except for you suckers working on legacy systems. I hope this helps, let me know one way or the other.
