How to Send Mail in the Future with Rails
This post was originally posted on Max's blog, Maxgrok.
This post assumes you already have setup Sidekiq, Sidetiq, Rails 5.1.2, and are familiar with the command line.
Let's run rails generate mailer InsertMailerName in the command line in the root directory of your Rails app.
This will create the following output in your terminal (minus the 'identical' files, it will just say created then the file name):
# app/mailers/insert_name_mailer.rb
class InsertNameMailer < ActionMailer::Base
default from: "from@example.com"
def welcome_email
mail(to: "to@example.com", subject: "Your Future Email")
end
end
Create a Mailer View by making a new file called app/views/insert_name_mailer/welcome_email.html.haml (or just .html if you do not have a .haml linter setup).
Inside that welcome_email.html.haml file, place the following code:
<!DOCTYPE html>
<html>
<head>
<meta content='text/html; charset=UTF-8' http-equiv='Content-Type' />
</head>
<body>
<h1>Welcome to example.com!</h1>
<p>
You have successfully signed up to example.com.<br>
</p>
<p>
To login to the site, just follow this link:<a href="http://www.example.com/">example.com</a>.
</p>
<p>Thanks for joining and have a great day!</p>
</body>
</html>
Go to app/workers/name_of_worker_worker.rb
You will see the following:
class NameOfWorkerWorker
include Sidekiq::Worker
def perform(*args)
# Do something
end
end
Let's add the mailer in the perform method.
class NameOfWorkerWorker
include Sidekiq::Worker
def perform(*args)
InsertNameMailer.welcome_email.deliver # calls the mailer we made's method and delivers the email immediately
end
end
Now, whenever the worker runs, it will send a welcome email.
Let's test this out.
Go to rails c test to load your test environment.
Inside the rails console, run NameOfWorker.new.perform.
If successful, you will see a load of text followed by an output that is green and looks like this:
=> #<Mail::Message:LongNumberHere>, Multipart: true, Headers: <Date: TodaysDateHere>, <From: "from@example.com">, <To: "to@example.com">, <Message-ID: <RandomStringOfLettersAndNumbersHere@YourComputer'sName>>,<Subject: "Your Future Email">, <Mime-Version: 1.0>, <Content-Type: multipart/alternative; boundary="--==mimepart_(randonstringoflettersandnumbers)"; charset=UTF-8>, <Content-Transfer-Encoding: 7bit>>
Now, let's add the scheduling to the Sidekiq Worker with one line thanks to Sidetiq!
class NameOfWorkerWorker
include Sidekiq::Worker
include Sidetiq::Schedulable # new line includes the Schedulable module from Sidetiq
recurrence { daily } # makes the worker run daily
def perform(*args)
InsertNameMailer.welcome_email.deliver # calls the mailer we made's method and delivers the email immediately
end
end
Congratulations your Sidekiq Worker now sends email daily!
Where ever you call your Sidekiq Worker, you will send an email daily in the future.