Question

I’ve got a mailer sending through a GMail account, and I want to test that ActionMailer can actually log in to GMail’s SMTP server with the credentials I’ve given it. What’s the best way to test this?

Answer 1

It’s not a full-stack solution, but you can check that the server authentication happens correctly by using Net::SMTP directly. The Mail gem that Rails 3 uses to send ActionMailer emails uses Mail like so (with your ActionMailer.smtp_settings):

  #line 96 of mail-2.2.7/lib/mail/network/delivery_methods/smtp.rb
  smtp = Net::SMTP.new(settings[:address], settings[:port])
  if settings[:enable_starttls_auto]
    smtp.enable_starttls_auto if smtp.respond_to?(:enable_starttls_auto) 
  end

  smtp.start(settings[:domain], settings[:user_name], settings[:password],
   settings[:authentication]) do |smtp|
     smtp.sendmail(message, envelope_from, destinations)
     # @Mason: this line need not be included in your code. SMTP#start throws
     # a Net::SMTPAuthenticationError if the authentication was not successful.
     # So just putting this call to #start with an empty block in a method and
     # calling assert_no_raise Net::SMTPAuthenticationError should do the trick.
     # The empty block is necessary so that the connection gets closed.
     # Reference #{rubydir}/lib/ruby/1.8/net/smtp.rb for more info.
  end

Looks like ActionMailer::Base.smtp_settings is accessible too:

  settings = ActionMailer::Base.smtp_settings

Putting that in your test and commenting out the line spoken of above should have a working example for you.