How to test email with Selenium

What you'll find in this guide

How to test various aspects of emails
Testing links and codes
Managing email tests

What you'll need

An understanding of Selenium and how it works.
A Mailosaur account with the SMS feature enabled. You can start a free trial if you don't have one.
A Selenium project with Mailosaur's API client configured. See our short guide on this.

Basic usage

To perform email testing with Selenium, all you need to do is:

Send an email message to your Mailosaur inbox (e.g. by requesting a password reset)
Connect to the Mailosaur API with the official client library.
Search for the email you sent in step 1.
Perform assertions in the same way you would for any other test.

To learn about Server IDs, and what to replace SERVER_ID with, see sending test emails to Mailosaur.

// Setup the API client
MailosaurClient mailosaur = new MailosaurClient("API_KEY");

MessageSearchParams params = new MessageSearchParams();
params.withServer("SERVER_ID");

SearchCriteria searchCriteria = new SearchCriteria();
searchCriteria.withSentTo("my-test@SERVER_ID.mailosaur.net");

// Search for the message
Message message = mailosaur.messages().get(params, searchCriteria);

// Perform test assertions
assertEquals("Support", message.from().get(0).name());
assertEquals("noreply@acme.com", message.from().get(0).phone());

This example will search for the email address that a message was sent to, but you can also search using any of the below criteria:

Parameter	Description
sentTo	The full email address to which the target message was sent
sentFrom	The full email address from which the target message was sent
subject	Finds messages where the subject line contains this text
body	Finds messages where the message body contains this text

Test email addresses

Each inbox in your account (also known as a server) has a unique identifier, referred to as a Server ID. This ID is used to give your inbox a domain name like this: SERVER_ID.mailosaur.net.

This domain supports a wildcard email pattern, meaning any email address ending @SERVER_ID.mailosaur.net works out the box.

You don't need to create email addresses before using item, they just work! However, if you need help thinking of a unique email address, you can use this helper method:

String emailAddress = mailosaur.servers().generateEmailAddress("SERVER_ID");

System.out.println(emailAddress); // "bgwqj@SERVER_ID.mailosaur.net"

Find an email

Search for a specific message within your inbox, it's always better to use messages.get(), as it will automatically wait for messages to arrive, and will return the full message result.

MessageSearchParams params = new MessageSearchParams();
params.withServer("SERVER_ID");

SearchCriteria searchCriteria = new SearchCriteria();
searchCriteria.withSentTo("test123@SERVER_ID.mailosaur.net");

Message message = mailosaur.messages().get(params, searchCriteria);

System.out.println(message.html().body());

Other ways to fetch emails

It is usually better to use messages.get()

The list and search methods will only return basic summaries, meaning several properties (including the message body) are not included. To get this data, you need to use .getById(). Instead, we recommend using the messages.get() as this automatically waits for a matching result and returns the message in the result.

List current inbox contents

See a full list of everything currently in your inbox.

// List the most recent messages
MessageListParams params = new MessageListParams();
params.withServer("SERVER_ID");
MessageListResult result = mailosaur.messages().list(params);

// Get the most recent message (the first one in the list)
MessageSummary latestMessage = result.items().get(0);

// Get the full message object
Message message = mailosaur.messages().getById(latestMessage.id());

System.out.println(message.html().body());

Searching for multiple messages

Identify if multiple messages meet the same criteria.

// Search for all messages sent to someone@SERVER_ID.mailosaur.net.
// Limit results to the first 10 matches only.
MessageSearchParams params = new MessageSearchParams();
params.withServer("SERVER_ID")
  .withPage(0)
  .withItemsPerPage(10);

MessageListResult result = mailosaur.messages().search(params, criteria);

// Get the most recent message (the first one in the list)
MessageSummary latestMessage = result.items().get(0);

// Get the full message object
Message message = mailosaur.messages().getById(latestMessage.id());

System.out.println(message.html().body());

Common test scenarios

Testing basic properties

Once you have fetched an email (e.g. using messages.get), you can easily test the properties of that email:

// Test the email subject line
assertEquals("Password reset", message.subject());

// Test sender information
assertEquals("Support", message.from().get(0).name());
assertEquals("noreply@acme.com", message.from().get(0).email());

// Test recipient information
assertEquals("John Smith", message.to().get(0).name());
assertEquals("john@SERVER.mailosaur.net", message.to().get(0).email());

Testing carbon-copy recipients

// Carbon copy (CC) recipients
assertEquals("Jane Smith", message.cc().get(0).name());
assertEquals("jane@SERVER.mailosaur.net", message.cc().get(0).email());

// Blind carbon copy (BCC) recipients
assertEquals("Jill Smith", message.bcc().get(0).name());
assertEquals("jill@SERVER.mailosaur.net", message.bcc().get(0).email());

Testing email contents

Most emails will contain separate HTML and plain text content. You can see below how to test either content type:

Plain text content

// Check that the email contains some text
System.out.println(message.text().body()); // "Hi Jason, ..."

HTML content

When testing HTML content, you can perform basic contains or equals assertions in the same way as with plain text content:

// Check that raw HTML contains some expected content
System.out.println(message.html().body()); // "<span>Hello world</span>"

Testing links

Any links that are found in the content of your email are instantly available via the html.links or text.links arrays, depending on which content the link was found in:

// Working with links in HTML content
Link linkInHtml = message.text().links().get(0);
assertEquals("Google Search", linkInHtml.text());
assertEquals("https://www.google.com/", linkInHtml.href());

// Working with links in plain text content
Link linkInPlainText = message.text().links().get(0);
assertEquals("https://www.google.com/", linkInPlainText.href());

Clicking a link

If you just need to simulate a link being clicked and do not need to do anything on the target page, you can do this with HttpClient:

String href = message.html().links().get(0).href();

// Make an HTTP call to simulate someone clicking a link
var client = HttpClient.newHttpClient();
var request = HttpRequest.newBuilder(URI.create(href)).build();
var response = client.send(request, null);
System.out.println(response.statusCode()); // 200

Testing verification codes

Codes are automatically extracted from the content of your message. They are then made available via the html.codes or text.codes arrays:

// Working with codes in HTML content
Link codeInHtml = message.html().codes().get(0);
assertEquals("456812", codeInHtml.value());

// Working with codes in plain text content
Link codeInHtml = message.text().codes().get(0);
assertEquals("456812", codeInHtml.value());

Testing attachments

Any email attachments are made available via the attachments array:

// Number of attachments found
System.out.println(message.attachments().size()); // 2

// Get the first attachment
Attachment attachment = message.attachments().get(0);

// Check attachment attributes
assertEquals("example.pdf", attachment.fileName());
assertEquals("application/pdf", attachment.contentType());

assertEquals(4028, attachment.length());

Save an attachment to disk

You can download and save attachments using the files.getAttachment and Files.write methods:

Attachment firstAttachment = message.attachments().get(0);
byte[] file = mailosaur.files().getAttachment(firstAttachment.id());
Files.write(Paths.get(firstAttachment.fileName()), file);

Encoding attachments

In some scenarios you may need a base64-encoded copy of an attachment. You can achieve this using Base64.getEncoder:

Attachment firstAttachment = message.attachments().get(0);
byte[] file = mailosaur.files().getAttachment(firstAttachment.id());
String base64 = new String(Base64.getEncoder().encode(file));
System.out.println(base64);

Testing images and web beacons

Any images found within the HTML content of an email are made available via the html.images array:

// Number of images found
System.out.println(message.html().images().size());

// Get the first attachment
var image = message.html().images().get(0);

// Check image attributes
assertEquals("https://example.com/balloon.png", image.src());
assertEquals("A hot air balloon", image.alt());

To test whether an image is accessible online, or that a web beacon is working as expected, you can simply perform an HTTP request:

// Make an HTTP call to trigger the web beacon
var client = HttpClient.newHttpClient();
var request = HttpRequest.newBuilder(URI.create(image.src())).build();
var response = client.send(request, null);
System.out.println(response.statusCode()); // 200

Sending an email

If your product is capable of handling inbound emails, you can use Mailosaur’s sending feature to trigger this functionality in your product.

The messages.create command creates and sends an email to a verified external email address:

CodeMessageCreateOptions options = new MessageCreateOptions();
options.withTo("verified-address@example.com")
  .withSend(true)
  .withSubject("Request")
  .withText("Please can you give us a call back?");

mailosaur.messages().create("SERVER_ID", options);

The options available to use with this method are:

Parameter	Description
send	This must be set to true if you are sending an outbound email
to	The email address to which the email will be sent. Must be a verified email address.
subject	The email subject line
text	The plain text body of the email.
html	The HTML body of the email.
attachments	Optional attachments (see 'include attachments' below)

Include attachments

You can include attachments in emails sent via the API, by including an array of base64-encoded attachment objects:

Attachment attachment = new Attachment();
		attachment.withFileName("cat.png");
		attachment.withContent("{BASE64_ENCODED_FILE}");
		attachment.withContentType("image/png");

CodeMessageCreateOptions options = new MessageCreateOptions();
options.withTo("verified-address@example.com")
  .withSend(true)
  .withSubject("Request")
  .withText("Please can you give us a call back?")
  .withAttachments(Arrays.asList(new Attachment[] { attachment }));

mailosaur.messages().create("SERVER_ID", options);

Replying to an email

If your product is capable of handling SMS replies from your customers, you can use Mailosaur’s reply feature to simulate this. When you reply, the SMS is sent back to the phone number it was originally sent to Mailosaur from:

MessageReplyOptions options = new MessageReplyOptions();
options.withText("FYI");

mailosaur.messages().reply("MESSAGE_ID", options);

Parameter	Description
text	Any additional text content to include in the reply
html	Any additional HTML content to include in the reply
subject	Optionally override the default subject line
attachments	Optional attachments (see 'include attachments' above)

Forwarding a message to email

You can forward messages from your Mailosaur account to external email addresses either one-by-one, or via the creation of automated forwarding rules. Before you can forward messages, you must set up a verified external email address, so you can send email to it:

MessageForwardOptions options = new MessageForwardOptions();
options.withTo("verified-address@example.com")
  .withText("FYI");

mailosaur.messages().forward("MESSAGE_ID", options);

Parameter	Description
to	The email address to which the message will be sent. Must be a verified email address
text	Any additional text content to forward the message with
html	Any additional HTML content to forward the message with
subject	Optionally override the default subject line

Deleting messages

Deleting an individual message

Permanently deletes a single message. Also deletes any attachments related to the message. This operation cannot be undone:

mailosaur.messages().delete("MESSAGE_ID");

Delete all messages

Permanently deletes all messages held in the specified server/inbox. Also deletes any attachments related to each message. This operation cannot be undone:

mailosaur.messages().deleteAll("SERVER_ID");

Email testing for Selenium

What you'll find in this guide

What you'll need

Basic usage

Test email addresses

Find an email

Other ways to fetch emails

It is usually better to use `messages.get()`

List current inbox contents

Searching for multiple messages

Common test scenarios

Testing basic properties

Testing carbon-copy recipients

Testing email contents

Plain text content

HTML content

Testing links

Clicking a link

Testing verification codes

Testing attachments

Save an attachment to disk

Encoding attachments

Testing images and web beacons

Sending an email

Include attachments

Replying to an email

Forwarding a message to email

Deleting messages

Deleting an individual message

Delete all messages

See also

Email testing for Selenium

What you'll find in this guide

What you'll need

Basic usage

Test email addresses

Find an email

Other ways to fetch emails

It is usually better to use messages.get()

List current inbox contents

Searching for multiple messages

Common test scenarios

Testing basic properties

Testing carbon-copy recipients

Testing email contents

Plain text content

HTML content

Testing links

Clicking a link

Testing verification codes

Testing attachments

Save an attachment to disk

Encoding attachments

Testing images and web beacons

Sending an email

Include attachments

Replying to an email

Forwarding a message to email

Deleting messages

Deleting an individual message

Delete all messages

See also

It is usually better to use `messages.get()`