Mailing

Note: This section is under development.

Yii supports composition and sending of the email messages. However, the framework core provides only the content composition functionality and basic interface. Actual mail sending mechanism should be provided by the extension, because different projects may require its different implementation and it usually depends on the external services and libraries.

For the most common cases you can use yii2-swiftmailer official extension.

Configuration

Mail component configuration depends on the extension you have chosen. In general your application configuration should look like:

return [
    //....
    'components' => [
        'mailer' => [
            'class' => 'yii\swiftmailer\Mailer',
        ],
    ],
];

Basic usage

Once the mailer component is configured, you can use the following code to send an email message:

Yii::$app->mailer->compose()
    ->setFrom('from@domain.com')
    ->setTo('to@domain.com')
    ->setSubject('Message subject')
    ->setTextBody('Plain text content')
    ->setHtmlBody('<b>HTML content</b>')
    ->send();

In the above example the method compose() creates an instance of the mail message, which then is populated and sent. You may put more complex logic in this process if needed:

$message = Yii::$app->mailer->compose();
if (Yii::$app->user->isGuest) {
    $message->setFrom('from@domain.com');
} else {
    $message->setFrom(Yii::$app->user->identity->email);
}
$message->setTo(Yii::$app->params['adminEmail'])
    ->setSubject('Message subject')
    ->setTextBody('Plain text content')
    ->send();

Note: each mailer extension comes in 2 major classes: Mailer and Message. Mailer always knows the class name and specific of the Message. Do not attempt to instantiate Message object directly — always use compose() method for it.

You may also send several messages at once:

$messages = [];
foreach ($users as $user) {
    $messages[] = Yii::$app->mailer->compose()
        // ...
        ->setTo($user->email);
}
Yii::$app->mailer->sendMultiple($messages);

Some particular mail extensions may benefit from this approach, using single network message etc.

Composing mail content

Yii allows composition of the actual mail messages content via special view files. By default these files should be located at @app/mail path.

Example mail view file content:

<?php
use yii\helpers\Html;
use yii\helpers\Url;

/* @var $this \yii\web\View view component instance */
/* @var $message \yii\mail\BaseMessage instance of newly created mail message */

?>
<h2>This message allows you to visit our site home page by one click</h2>
<?= Html::a('Go to home page', Url::home('http')) ?>

In order to compose message content via view file simply pass view name to the compose() method:

Yii::$app->mailer->compose('home-link') // a view rendering result becomes the message body here
    ->setFrom('from@domain.com')
    ->setTo('to@domain.com')
    ->setSubject('Message subject')
    ->send();

You may pass additional view parameters to compose() method, which will be available inside the view files:

Yii::$app->mailer->compose('greetings', [
    'user' => Yii::$app->user->identity,
    'advertisement' => $adContent,
]);

You can specify different view files for HTML and plain text message contents:

Yii::$app->mailer->compose([
    'html' => 'contact-html',
    'text' => 'contact-text',
]);

If you specify view name as a scalar string, its rendering result will be used as HTML body, while plain text body will be composed by removing all HTML entities from HTML one.

View rendering result can be wrapped into the layout, which can be setup using yii\mail\BaseMailer::$htmlLayout and yii\mail\BaseMailer::$textLayout. It will work the same way like layouts in regular web application. Layout can be used to setup mail CSS styles or other shared content:

<?php
use yii\helpers\Html;

/* @var $this \yii\web\View view component instance */
/* @var $message \yii\mail\MessageInterface the message being composed */
/* @var $content string main view render result */
?>
<?php $this->beginPage() ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=<?= Yii::$app->charset ?>" />
    <style type="text/css">
        .heading {...}
        .list {...}
        .footer {...}
    </style>
    <?php $this->head() ?>
</head>
<body>
    <?php $this->beginBody() ?>
    <?= $content ?>
    <div class="footer">With kind regards, <?= Yii::$app->name ?> team</div>
    <?php $this->endBody() ?>
</body>
</html>
<?php $this->endPage() ?>

File attachment

You can add attachments to message using methods attach() and attachContent():

$message = Yii::$app->mailer->compose();

// attach file from local file system
$message->attach('/path/to/source/file.pdf');

// create attachment on-the-fly
$message->attachContent('Attachment content', ['fileName' => 'attach.txt', 'contentType' => 'text/plain']);

Embedding images

You can embed images into the message content using embed() method. This method returns the attachment id, which should be then used at img tag. This method is easy to use when composing message content via view file:

Yii::$app->mailer->compose('embed-email', ['imageFileName' => '/path/to/image.jpg'])
    // ...
    ->send();

Then inside the view file you can use the following code:

<img src="<?= $message->embed($imageFileName); ?>">

Testing and debugging

A developer often has to check, what actual emails are sent by the application, what was their content and so on. Such ability is granted by Yii via yii\mail\BaseMailer::useFileTransport. If enabled, this option enforces saving mail message data into the local files instead of regular sending. These files will be saved under yii\mail\BaseMailer::fileTransportPath, which is @runtime/mail by default.

Note: you can either save the messages to the files or send them to the actual recipients, but can not do both simultaneously.

A mail message file can be opened by a regular text file editor, so you can browse the actual message headers, content and so on. This mechanism may prove itself, while debugging application or running unit test.

Note: the mail message file content is composed via \yii\mail\MessageInterface::toString(), so it depends on the actual mail extension you are using in your application.

Creating your own mail solution

In order to create your own custom mail solution, you need to create 2 classes: one for the Mailer and another one for the Message. You can use yii\mail\BaseMailer and yii\mail\BaseMessage as the base classes for your solution. These classes already contain the basic logic, which is described in this guide. However, their usage is not mandatory, it is enough to implement yii\mail\MailerInterface and yii\mail\MessageInterface interfaces. Then you need to implement all the abstract methods to build your solution.