Getting Started with Ruby

Learn how to automate email testing in Ruby

Testing email in Ruby

Learn how to automate email testing in Ruby.

Before you start

If you don’t already have one, create a Mailosaur account.

Make sure you know [how to send email to Mailosaur/docs/email-testing/overview/sending-emails first. Once you have this working, you’re ready to start testing!

Installing Mailosaur

Mailosaur provides an official Ruby client library to make testing email in Ruby a lot easier.

Install via gem:

gem install mailosaur

Authenticating with Mailosaur

In order to connect to Mailosaur, you need to add your API key to your tests. You access your API key via the account settings screen.

Retrieving an email

Once you have sent an email to test, for example by emailing something.{SERVER_ID}, you can now use the code below to retrieve the message in Ruby:

# 1. Import Mailosaur and create an instance of the MailosaurClient, using your API key
require "mailosaur"
client ="{API_KEY}")

# 2. Build search criteria to find the email you have sent
criteria =
criteria.sent_to = "something.{SERVER_ID}"

# 3. Wait for the message (by default only looks for messages received in the last hour)
message = client.messages.get("{SERVER_ID}", criteria)

# 4. Assert that the email subject is what we expect
assert_equal("Reset your password", message.subject)

Mailosaur extracts any links found within both the HTML and text content of an email. These are then made available via message.html.links and message.text.links.

You can use these links for many scenarios, such as completing a password reset process:

# Wait for the message
message = client.messages.get("{SERVER_ID}", criteria)

# Check that we have the password reset email
assert_equal("Reset your password", message.subject)

# Store the password reset link (e.g. to use in a test that completes the process)
password_reset_link = message.text.links[0].href;

Extracting content from email HTML

If you need to extract content from the body of an email, such as a verification code, then you can use a library in your tests.

Let’s imagine that message.html.body contains:

  <h1>To activate your account, enter this code:</h1>
  <p class="verify-code">542163</p>

To work with the email’s HTML, install nokogiri via gem:

gem install nokogiri

Import nokogiri at the top of your test file:

require 'nokogiri'

Now, you can extract the verification code as follows:

# Wait for the message
message = client.messages.get("{SERVER_ID}", criteria)

# Extract the verification code from HTML
@doc = Nokogiri::HTML(message.body.html)
verification_code = @doc.css(".verify-code").text

puts verification_code