I saw this post but mine is slightly different:
Rails ActionMailer with multiple SMTP servers
I am allowing the users to send mail using their own SMTP credentials so it actually does come from them.
But they will be sent from the Rails app, so that means for each user I need to send their emails using their own SMTP server.
How can I do that?
Just set the ActionMailer::Base configuration values before each send action.
smtp_config = user.smtp_configuration
ActionMailer::Base.username = smtp_config.username
ActionMailer::Base.password = smtp_config.password
ActionMailer::Base.server = ..
ActionMailer::Base.port = ..
ActionMailer::Base.authentication = ..
Doing what is described in the other answer is not safe; you are setting class variables here, not instanced variables. If your Rails container is forking, you can do this, but now your application is depending on an implementation detail of the container. If you're not forking a new Ruby process, then you can have a race condition here.
You should have a model that is extending ActionMailer::Base, and when you call a method, it will return a Mail::Message object. That is your instance object and is where you should change your settings. The settings are also just a hash, so you can inline it.
msg = MyMailer.some_message
msg.delivery_method.settings.merge!(@user.mail_settings)
msg.deliver
Where in the above mail_settings returns some hash with appropriate keys IE
{:user_name=>username, :password=>password}
Here is a solution that I came up with based on the previous answers and comments. This uses an ActionMailer interceptor class.
class UserMailer < ActionMailer::Base
default from: proc{ @user.mail_settings[:from_address] }
class DynamicSettingsInterceptor
def self.delivering_email(message)
message.delivery_method.settings.merge!(@user.mail_settings)
end
end
register_interceptor DynamicSettingsInterceptor
end
For Rails 3.2.x
You can include AbstractController::Callbacks in your mailer class and the do a "after_filter :set_delivery_options" inside the mailer.
The set_delivery_options method would have access to instance variables setup by you in your mailer action and you can access the mail object as "message".
class MyNailer < ActionMailer::Base
include AbstractController::Callbacks
after_filter :set_delivery_options
def nail_it(user)
@user = user
mail :subject => "you nailed it"
end
private
def set_delivery_options
message.delivery_method.settings.merge!(@user.company.smtp_creds)
end
end
in case somebody needs to set delivery method dynamically together with smtp credentials, u can use Mail::Message instance method to set delivery method together with it's variables so my addapted Aditya Sanghi version is:
class MainMailer < ActionMailer::Base
WHATEVER_CONDITION = true # example only f.e. @ser
include AbstractController::Callbacks
after_filter :set_delivery_options
private
def set_delivery_options
settings = {
:address => 'smtp.mandrillapp.com', # intentionally
:port => 587, # intentionally
:domain => 'your_domain', #insetad of localhost.localdomain'
:user_name => 'smtp_username',
:password => 'smtp_password',
:authentication => 'PLAIN' # or smthing else
}
if WHATEVER_CONDITION
message.delivery_method(:smtp, settings)
end
end
end
Since Rails 4+ it works to give the credentials directly via the delivery_method_options parameter:
class UserMailer < ApplicationMailer
def welcome_email
@user = params[:user]
@url = user_url(@user)
delivery_options = { user_name: params[:company].smtp_user,
password: params[:company].smtp_password,
address: params[:company].smtp_host }
mail(to: @user.email,
subject: "Please see the Terms and Conditions attached",
delivery_method_options: delivery_options)
end
end
See Sending Emails with Dynamic Delivery Options (Rails Guides)