Test emails using Redis

Simple gem for testing emails using Redis. It is ready to test for asynchronous emails (using Sidekiq or Resque gems).

Overview

Usage

Gemfile:

gem 'test_email_redis'

Application

Config gem:

# config/initializers/test_email_redis.rb

TestEmailRedis.set_config({
  redis_prefix: "myapp_#{Rails.env}",
  field_user_id: :to
})

Configure mail delivery:

# config/environments/test.rb

Rails.application.configure do
...

    #
    require 'test_email_redis/test_mail_delivery'
    ActionMailer::Base.add_delivery_method :my_test_delivery, TestEmailRedis::TestMailDelivery
    config.action_mailer.delivery_method = :my_test_delivery

end

Tests: RSpec3

Require helpers in your tests and configure

# spec_helper.rb or rspec_helper.rb

require 'test_email_redis'
require 'test_email_redis/helpers'

TestEmailRedis.set_config({
  redis_prefix: "myapp_test",
  field_user_id: :to
})

Test:

RSpec.describe "Register user", :type => :request do

  describe 'register user' do

    before :each do
      # delete all emails if needed
      TestEmailRedis::Helpers.clean_emails_all

    end

    after :each do
      TestEmailRedis::Helpers.clean_emails_all
    end


    it 'sends email' do
       # do smth that sends email

       email = 'myuser@gmail.com'

       #...
       UsersMailer.welcome(email)

       # check email is received
       # by default, it will wait till the email is received
       mail = TestEmailRedis::Helpers.get_last_email_for_user email

       expect(mail).to be_truthy

       # analyze mail content
       html = mail['parts'][0]['body']
       text = mail['parts'][1]['body']

       expect(html).to match(/Welcome/)

    end

  end
end

Mail delivery

The gem provides custom mailers:

TestMailDelivery - add mail message to Redis
TestMailSmtpDelivery - add mail message to Redis and send via SMTP

Use custom mail deliveries:

# config/environments/test.rb

Rails.application.configure do

require 'test_email_redis/test_mail_delivery'
ActionMailer::Base.add_delivery_method :my_test_delivery, TestEmailRedis::TestMailDelivery
# or
# ActionMailer::Base.add_delivery_method :my_test_delivery, TestEmailRedis::TestMailSmtpDelivery
config.action_mailer.delivery_method = :my_test_delivery

end

Test Helpers

TestEmailRedis::Helpers.get_last_email_for_user(user_id) - return the last email for user identified by user_id.

TestEmailRedis::get_last_email_for_user(user_id, wait=true, opts={})

Examples:

# do not wait for message
mail = TestEmailRedis::Helpers.get_last_email_for_user(user_id, false)

TestEmailRedis::n_emails_for_user(user_id) - number of emails for user
TestEmailRedis::wait_for_new_email_for_user(user_id) - just waits till a new message arrived
TestEmailRedis::clean_emails_all - delete all emails
TestEmailRedis::clean_emails_for_user - delete all emails for the user
TestEmailRedis::add_email_to_redis(mail) - adds email to Redis

Config options

field_user_id - field used to identify user by mail message. By default, :to which means what user_id = mail.to

Redis

Data stored in Redis:

<redis_prefix>:emails:content - hash with email contents: {mail_id: content, ..}
<redis_prefix>:emails:by_user:<user_id> - list of mail message IDs for the user: [id1, id2, id3,..]

Examples

Example. Get last email

email = 'myuser@gmail.com'

# emails could be already for the user
n_old = TestEmailRedis::Helpers.n_emails_for_user email

# do smth which might send email
UsersMailer.welcome(email)

# wait for a new message
mail = TestEmailRedis::Helpers.get_last_email_for_user email, true, {n_old_emails: n_old}

# ***WARNING!***
# Do not use TestEmailRedis::Helpers.get_last_email_for_user(email) - it might return an old email currently available in Redis.
# It will not work is asynchronous emails are used

or if you don't need old emails - just delete them before sending a new email:

email = 'myuser@gmail.com'

# emails could be already for the user
TestEmailRedis::Helpers.clean_emails_for_user email

# do smth which might send email
UsersMailer.welcome(email)

# wait for a new message
mail = TestEmailRedis::Helpers.get_last_email_for_user email

Example. Multiple emails in one test example

Multiple emails:

email = 'myuser@gmail.com'

# emails could be already for the user
n_old = TestEmailRedis::Helpers.n_emails_for_user email

# do smth which might send email
UsersMailer.welcome(email)
# so smth else
# send another email
UsersMailer.newsletter(email)

# for now, two emails has been sent.

# wait for a second message to arrive
mail = TestEmailRedis::Helpers.get_last_email_for_user email, true, {n_old_emails: n_old+1}

test_email_redis

Development

Runtime