Getting Started with Python

Learn how to automate email testing in Python

Before you start

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

Make sure you know how to send email to Mailosaur first. Once you have this working, you’re ready to start testing!

Installing Mailosaur

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

Install via pip:

pip install --upgrade 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 Python:

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

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

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

# 4. Assert that the email subject is what we expect
assertEqual("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
assertEqual("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;

Finding emails older than 1 hour

By default, the get method will only look for messages that were received by Mailosaur within the last hour. You can override this by setting a received_after value:

client.messages.get("{SERVER_ID}", criteria, received_after=( - timedelta(days=2)))

This code will perform the same query as above, but will now include messages received within the last 2 days.

Note that you’ll need to import datetime and timedelta for this to work:

from datetime import datetime, timedelta

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 Beautiful Soup via pip:

pip install beautifulsoup4

Import Beautiful Soup at the top of your test file:

from bs4 import BeautifulSoup

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
dom = BeautifulSoup(html, 'html.parser')
verification_code = dom.find('.verify-code').text