Creating Messages

Creating messages in Swift Mailer is done by making use of the various MIME entities provided with the library. Complex messages can be quickly created with very little effort.

Quick Reference for Creating a Message

You can think of creating a Message as being similar to the steps you perform when you click the Compose button in your mail client. You give it a subject, specify some recipients, add any attachments and write your message.

To create a Message:

  • Call the newInstance() method of Swift_Message.
  • Set your sender address (From:) with setFrom() or setSender().
  • Set a subject line with setSubject().
  • Set recipients with setTo(), setCc() and/or setBcc().
  • Set a body with setBody().
  • Add attachments with attach().
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require_once 'lib/swift_required.php';

// Create the message
$message = Swift_Message::newInstance()

  // Give the message a subject
  ->setSubject('Your subject')

  // Set the From address with an associative array
  ->setFrom(array('john@doe.com' => 'John Doe'))

  // Set the To addresses with an associative array
  ->setTo(array('receiver@domain.org', 'other@domain.org' => 'A name'))

  // Give it a body
  ->setBody('Here is the message itself')

  // And optionally an alternative body
  ->addPart('<q>Here is the message itself</q>', 'text/html')

  // Optionally add any attachments
  ->attach(Swift_Attachment::fromPath('my-document.pdf'))
  ;

Message Basics

A message is a container for anything you want to send to somebody else. There are several basic aspects of a message that you should know.

An e-mail message is made up of several relatively simple entities that are combined in different ways to achieve different results. All of these entities have the same fundamental outline but serve a different purpose. The Message itself can be defined as a MIME entity, an Attachment is a MIME entity, all MIME parts are MIME entities -- and so on!

The basic units of each MIME entity -- be it the Message itself, or an Attachment -- are its Headers and its body:

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Header-Name: A header value
Other-Header: Another value

The body content itself

The Headers of a MIME entity, and its body must conform to some strict standards defined by various RFC documents. Swift Mailer ensures that these specifications are followed by using various types of object, including Encoders and different Header types to generate the entity.

The Structure of a Message

Of all of the MIME entities, a message -- Swift_Message is the largest and most complex. It has many properties that can be updated and it can contain other MIME entities -- attachments for example -- nested inside it.

A Message has a lot of different Headers which are there to present information about the message to the recipients' mail client. Most of these headers will be familiar to the majority of users, but we'll list the basic ones. Although it's possible to work directly with the Headers of a Message (or other MIME entity), the standard Headers have accessor methods provided to abstract away the complex details for you. For example, although the Date on a message is written with a strict format, you only need to pass a UNIX timestamp to setDate().

Header Description Accessors
Message-ID Identifies this message with a unique ID, usually containing the domain name and time generated getId() / setId()
Return-Path Specifies where bounces should go (Swift Mailer reads this for other uses) getReturnPath() / setReturnPath()
From Specifies the address of the person who the message is from. This can be multiple addresses if multiple people wrote the message. getFrom() / setFrom()
Sender Specifies the address of the person who physically sent the message (higher precedence than From:) getSender() / setSender()
To Specifies the addresses of the intended recipients getTo() / setTo()
Cc Specifies the addresses of recipients who will be copied in on the message getCc() / setCc()
Bcc Specifies the addresses of recipients who the message will be blind-copied to. Other recipients will not be aware of these copies. getBcc() / setBcc()
Reply-To Specifies the address where replies are sent to getReplyTo() / setReplyTo()
Subject Specifies the subject line that is displayed in the recipients' mail client getSubject() / setSubject()
Date Specifies the date at which the message was sent getDate() / setDate()
Content-Type Specifies the format of the message (usually text/plain or text/html) getContentType() / setContentType()
Content-Transfer-Encoding Specifies the encoding scheme in the message getEncoder() / setEncoder()

Working with a Message Object

Although there are a lot of available methods on a message object, you only need to make use of a small subset of them. Usually you'll use setSubject(), setTo() and setFrom() before setting the body of your message with setBody().

Calling methods is simple. You just call them like functions, but using the object operator "->" to do so. If you've created a message object and called it $message then you'd set a subject on it like so:

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require_once 'lib/swift_required.php';

$message = Swift_Message::newInstance();
$message->setSubject('My subject');

All MIME entities (including a message) have a toString() method that you can call if you want to take a look at what is going to be sent. For example, if you echo $message->toString(); you would see something like this:

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Message-ID: <1230173678.4952f5eeb1432@swift.generated>
Date: Thu, 25 Dec 2008 13:54:38 +1100
Subject: Example subject
From: Chris Corbyn <chris@w3style.co.uk>
To: Receiver Name <recipient@example.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable

Here is the message

We'll take a closer look at the methods you use to create your message in the following sections.

Adding Content to Your Message

Rich content can be added to messages in Swift Mailer with relative ease by calling methods such as setSubject(), setBody(), addPart() and attach().

Setting the Subject Line

The subject line, displayed in the recipients' mail client can be set with the setSubject() method, or as a parameter to Swift_Message::newInstance().

To set the subject of your Message:

  • Call the setSubject() method of the Message, or specify it at the time you create the message.

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    // Pass it as a parameter when you create the message
    $message = Swift_Message::newInstance('My amazing subject');
    
    // Or set it after like this
    $message->setSubject('My amazing subject');
    

Setting the Body Content

The body of the message -- seen when the user opens the message -- is specified by calling the setBody() method. If an alternative body is to be included addPart() can be used.

The body of a message is the main part that is read by the user. Often people want to send a message in HTML format (text/html), other times people want to send in plain text (text/plain), or sometimes people want to send both versions and allow the recipient to choose how they view the message.

As a rule of thumb, if you're going to send a HTML email, always include a plain-text equivalent of the same content so that users who prefer to read plain text can do so.

To set the body of your Message:

  • Call the setBody() method of the Message, or specify it at the time you create the message.
  • Add any alternative bodies with addPart().

If the recipient's mail client offers preferences for displaying text vs. HTML then the mail client will present that part to the user where available. In other cases the mail client will display the "best" part it can - usually HTML if you've included HTML.

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// Pass it as a parameter when you create the message
$message = Swift_Message::newInstance('Subject here', 'My amazing body');

// Or set it after like this
$message->setBody('My <em>amazing</em> body', 'text/html');

// Add alternative parts with addPart()
$message->addPart('My amazing body in plain text', 'text/plain');

Attaching Files

Attachments are downloadable parts of a message and can be added by calling the attach() method on the message. You can add attachments that exist on disk, or you can create attachments on-the-fly.

Attachments are actually an interesting area of Swift Mailer and something that could put a lot of power at your fingertips if you grasp the concept behind the way a message is held together.

Although we refer to files sent over e-mails as "attachments" -- because they're attached to the message -- lots of other parts of the message are actually "attached" even if we don't refer to these parts as attachments.

File attachments are created by the Swift_Attachment class and then attached to the message via the attach() method on it. For all of the "every day" MIME types such as all image formats, word documents, PDFs and spreadsheets you don't need to explicitly set the content-type of the attachment, though it would do no harm to do so. For less common formats you should set the content-type -- which we'll cover in a moment.

Attaching Existing Files

Files that already exist, either on disk or at a URL can be attached to a message with just one line of code, using Swift_Attachment::fromPath().

You can attach files that exist locally, or if your PHP installation has allow_url_fopen turned on you can attach files from other websites.

To attach an existing file:

  • Create an attachment with Swift_Attachment::fromPath().
  • Add the attachment to the message with attach().

The attachment will be presented to the recipient as a downloadable file with the same filename as the one you attached.

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// Create the attachment
// * Note that you can technically leave the content-type parameter out
$attachment = Swift_Attachment::fromPath('/path/to/image.jpg', 'image/jpeg');

// Attach it to the message
$message->attach($attachment);


// The two statements above could be written in one line instead
$message->attach(Swift_Attachment::fromPath('/path/to/image.jpg'));


// You can attach files from a URL if allow_url_fopen is on in php.ini
$message->attach(Swift_Attachment::fromPath('http://site.tld/logo.png'));

Setting the Filename

Usually you don't need to explicitly set the filename of an attachment because the name of the attached file will be used by default, but if you want to set the filename you use the setFilename() method of the Attachment.

To change the filename of an attachment:

  • Call its setFilename() method.

The attachment will be attached in the normal way, but meta-data sent inside the email will rename the file to something else.

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// Create the attachment and call its setFilename() method
$attachment = Swift_Attachment::fromPath('/path/to/image.jpg')
  ->setFilename('cool.jpg');


// Because there's a fluid interface, you can do this in one statement
$message->attach(
  Swift_Attachment::fromPath('/path/to/image.jpg')->setFilename('cool.jpg')
);

Attaching Dynamic Content

Files that are generated at runtime, such as PDF documents or images created via GD can be attached directly to a message without writing them out to disk. Use the standard Swift_Attachment::newInstance() method.

To attach dynamically created content:

  • Create your content as you normally would.
  • Create an attachment with Swift_Attachment::newInstance(), specifying the source data of your content along with a name and the content-type.
  • Add the attachment to the message with attach().

The attachment will be presented to the recipient as a downloadable file with the filename and content-type you specify.

Note

If you would usually write the file to disk anyway you should just attach it with Swift_Attachment::fromPath() since this will use less memory:

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// Create your file contents in the normal way, but don't write them to disk
$data = create_my_pdf_data();

// Create the attachment with your data
$attachment = Swift_Attachment::newInstance($data, 'my-file.pdf', 'application/pdf');

// Attach it to the message
$message->attach($attachment);


// You can alternatively use method chaining to build the attachment
$attachment = Swift_Attachment::newInstance()
  ->setFilename('my-file.pdf')
  ->setContentType('application/pdf')
  ->setBody($data)
  ;

Changing the Disposition

Attachments just appear as files that can be saved to the Desktop if desired. You can make attachment appear inline where possible by using the setDisposition() method of an attachment.

To make an attachment appear inline:

  • Call its setDisposition() method.

The attachment will be displayed within the email viewing window if the mail client knows how to display it.

Note

If you try to create an inline attachment for a non-displayable file type such as a ZIP file, the mail client should just present the attachment as normal:

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// Create the attachment and call its setDisposition() method
$attachment = Swift_Attachment::fromPath('/path/to/image.jpg')
  ->setDisposition('inline');


// Because there's a fluid interface, you can do this in one statement
$message->attach(
  Swift_Attachment::fromPath('/path/to/image.jpg')->setDisposition('inline')
);

Embedding Inline Media Files

Often people want to include an image or other content inline with a HTML message. It's easy to do this with HTML linking to remote resources, but this approach is usually blocked by mail clients. Swift Mailer allows you to embed your media directly into the message.

Mail clients usually block downloads from remote resources because this technique was often abused as a mean of tracking who opened an email. If you're sending a HTML email and you want to include an image in the message another approach you can take is to embed the image directly.

Swift Mailer makes embedding files into messages extremely streamlined. You embed a file by calling the embed() method of the message, which returns a value you can use in a src or href attribute in your HTML.

Just like with attachments, it's possible to embed dynamically generated content without having an existing file available.

The embedded files are sent in the email as a special type of attachment that has a unique ID used to reference them within your HTML attributes. On mail clients that do not support embedded files they may appear as attachments.

Although this is commonly done for images, in theory it will work for any displayable (or playable) media type. Support for other media types (such as video) is dependent on the mail client however.

Embedding Existing Files

Files that already exist, either on disk or at a URL can be embedded in a message with just one line of code, using Swift_EmbeddedFile::fromPath().

You can embed files that exist locally, or if your PHP installation has allow_url_fopen turned on you can embed files from other websites.

To embed an existing file:

  • Create a message object with Swift_Message::newInstance().
  • Set the body as HTML, and embed a file at the correct point in the message with embed().

The file will be displayed with the message inline with the HTML wherever its ID is used as a src attribute.

Note

Swift_Image and Swift_EmbeddedFile are just aliases of one another. Swift_Image exists for semantic purposes.

Note

You can embed files in two stages if you prefer. Just capture the return value of embed() in a variable and use that as the src attribute.

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// Create the message
$message = Swift_Message::newInstance('My subject');

// Set the body
$message->setBody(
'<html>' .
' <head></head>' .
' <body>' .
'  Here is an image <img src="' . // Embed the file
     $message->embed(Swift_Image::fromPath('image.png')) .
   '" alt="Image" />' .
'  Rest of message' .
' </body>' .
'</html>',
  'text/html' // Mark the content-type as HTML
);

// You can embed files from a URL if allow_url_fopen is on in php.ini
$message->setBody(
'<html>' .
' <head></head>' .
' <body>' .
'  Here is an image <img src="' .
     $message->embed(Swift_Image::fromPath('http://site.tld/logo.png')) .
   '" alt="Image" />' .
'  Rest of message' .
' </body>' .
'</html>',
  'text/html'
);


// If placing the embed() code inline becomes cumbersome
// it's easy to do this in two steps
$cid = $message->embed(Swift_Image::fromPath('image.png'));

$message->setBody(
'<html>' .
' <head></head>' .
' <body>' .
'  Here is an image <img src="' . $cid . '" alt="Image" />' .
'  Rest of message' .
' </body>' .
'</html>',
  'text/html' // Mark the content-type as HTML
);

Embedding Dynamic Content

Images that are generated at runtime, such as images created via GD can be embedded directly to a message without writing them out to disk. Use the standard Swift_Image::newInstance() method.

To embed dynamically created content:

  • Create a message object with Swift_Message::newInstance().
  • Set the body as HTML, and embed a file at the correct point in the message with embed(). You will need to specify a filename and a content-type.

The file will be displayed with the message inline with the HTML wherever its ID is used as a src attribute.

Note

Swift_Image and Swift_EmbeddedFile are just aliases of one another. Swift_Image exists for semantic purposes.

Note

You can embed files in two stages if you prefer. Just capture the return value of embed() in a variable and use that as the src attribute.

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// Create your file contents in the normal way, but don't write them to disk
$img_data = create_my_image_data();

// Create the message
$message = Swift_Message::newInstance('My subject');

// Set the body
$message->setBody(
'<html>' .
' <head></head>' .
' <body>' .
'  Here is an image <img src="' . // Embed the file
     $message->embed(Swift_Image::newInstance($img_data, 'image.jpg', 'image/jpeg')) .
   '" alt="Image" />' .
'  Rest of message' .
' </body>' .
'</html>',
  'text/html' // Mark the content-type as HTML
);


// If placing the embed() code inline becomes cumbersome
// it's easy to do this in two steps
$cid = $message->embed(Swift_Image::newInstance($img_data, 'image.jpg', 'image/jpeg'));

$message->setBody(
'<html>' .
' <head></head>' .
' <body>' .
'  Here is an image <img src="' . $cid . '" alt="Image" />' .
'  Rest of message' .
' </body>' .
'</html>',
  'text/html' // Mark the content-type as HTML
);

Adding Recipients to Your Message

Recipients are specified within the message itself via setTo(), setCc() and setBcc(). Swift Mailer reads these recipients from the message when it gets sent so that it knows where to send the message to.

Message recipients are one of three types:

  • To: recipients -- the primary recipients (required)
  • Cc: recipients -- receive a copy of the message (optional)
  • Bcc: recipients -- hidden from other recipients (optional)

Each type can contain one, or several addresses. It's possible to list only the addresses of the recipients, or you can personalize the address by providing the real name of the recipient.

Make sure to add only valid email addresses as recipients. If you try to add an invalid email address with setTo(), setCc() or setBcc(), Swift Mailer will throw a Swift_RfcComplianceException.

If you add recipients automatically based on a data source that may contain invalid email addresses, you can prevent possible exceptions by validating the addresses using Swift_Validate::email($email) and only adding addresses that validate. Another way would be to wrap your setTo(), setCc() and setBcc() calls in a try-catch block and handle the Swift_RfcComplianceException in the catch block.

If you only wish to refer to a single email address (for example your From: address) then you can just use a string.

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$message->setFrom('some@address.tld');

If you want to include a name then you must use an associative array.

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$message->setFrom(array('some@address.tld' => 'The Name'));

If you want to include multiple addresses then you must use an array.

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$message->setTo(array('some@address.tld', 'other@address.tld'));

You can mix personalized (addresses with a name) and non-personalized addresses in the same list by mixing the use of associative and non-associative array syntax.

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$message->setTo(array(
  'recipient-with-name@example.org' => 'Recipient Name One',
  'no-name@example.org', // Note that this is not a key-value pair
  'named-recipient@example.org' => 'Recipient Name Two'
));

Setting To: Recipients

To: recipients are required in a message and are set with the setTo() or addTo() methods of the message.

To set To: recipients, create the message object using either new Swift_Message( ... ) or Swift_Message::newInstance( ... ), then call the setTo() method with a complete array of addresses, or use the addTo() method to iteratively add recipients.

The setTo() method accepts input in various formats as described earlier in this chapter. The addTo() method takes either one or two parameters. The first being the email address and the second optional parameter being the name of the recipient.

To: recipients are visible in the message headers and will be seen by the other recipients.

Note

Multiple calls to setTo() will not add new recipients -- each call overrides the previous calls. If you want to iteratively add recipients, use the addTo() method.

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// Using setTo() to set all recipients in one go
$message->setTo(array(
  'person1@example.org',
  'person2@otherdomain.org' => 'Person 2 Name',
  'person3@example.org',
  'person4@example.org',
  'person5@example.org' => 'Person 5 Name'
));

// Using addTo() to add recipients iteratively
$message->addTo('person1@example.org');
$message->addTo('person2@example.org', 'Person 2 Name');

Setting Cc: Recipients

Cc: recipients are set with the setCc() or addCc() methods of the message.

To set Cc: recipients, create the message object using either new Swift_Message( ... ) or Swift_Message::newInstance( ... ), then call the setCc() method with a complete array of addresses, or use the addCc() method to iteratively add recipients.

The setCc() method accepts input in various formats as described earlier in this chapter. The addCc() method takes either one or two parameters. The first being the email address and the second optional parameter being the name of the recipient.

Cc: recipients are visible in the message headers and will be seen by the other recipients.

Note

Multiple calls to setCc() will not add new recipients -- each call overrides the previous calls. If you want to iteratively add Cc: recipients, use the addCc() method.

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// Using setCc() to set all recipients in one go
$message->setCc(array(
  'person1@example.org',
  'person2@otherdomain.org' => 'Person 2 Name',
  'person3@example.org',
  'person4@example.org',
  'person5@example.org' => 'Person 5 Name'
));

// Using addCc() to add recipients iteratively
$message->addCc('person1@example.org');
$message->addCc('person2@example.org', 'Person 2 Name');

Setting Bcc: Recipients

Bcc: recipients receive a copy of the message without anybody else knowing it, and are set with the setBcc() or addBcc() methods of the message.

To set Bcc: recipients, create the message object using either new Swift_Message( ... ) or Swift_Message::newInstance( ... ), then call the setBcc() method with a complete array of addresses, or use the addBcc() method to iteratively add recipients.

The setBcc() method accepts input in various formats as described earlier in this chapter. The addBcc() method takes either one or two parameters. The first being the email address and the second optional parameter being the name of the recipient.

Only the individual Bcc: recipient will see their address in the message headers. Other recipients (including other Bcc: recipients) will not see the address.

Note

Multiple calls to setBcc() will not add new recipients -- each call overrides the previous calls. If you want to iteratively add Bcc: recipients, use the addBcc() method.

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// Using setBcc() to set all recipients in one go
$message->setBcc(array(
  'person1@example.org',
  'person2@otherdomain.org' => 'Person 2 Name',
  'person3@example.org',
  'person4@example.org',
  'person5@example.org' => 'Person 5 Name'
));

// Using addBcc() to add recipients iteratively
$message->addBcc('person1@example.org');
$message->addBcc('person2@example.org', 'Person 2 Name');

Specifying Sender Details

An email must include information about who sent it. Usually this is managed by the From: address, however there are other options.

The sender information is contained in three possible places:

  • From: -- the address(es) of who wrote the message (required)
  • Sender: -- the address of the single person who sent the message (optional)
  • Return-Path: -- the address where bounces should go to (optional)

You must always include a From: address by using setFrom() on the message. Swift Mailer will use this as the default Return-Path: unless otherwise specified.

The Sender: address exists because the person who actually sent the email may not be the person who wrote the email. It has a higher precedence than the From: address and will be used as the Return-Path: unless otherwise specified.

Setting the From: Address

A From: address is required and is set with the setFrom() method of the message. From: addresses specify who actually wrote the email, and usually who sent it.

What most people probably don't realise is that you can have more than one From: address if more than one person wrote the email -- for example if an email was put together by a committee.

To set the From: address(es):

  • Call the setFrom() method on the Message.

The From: address(es) are visible in the message headers and will be seen by the recipients.

Note

If you set multiple From: addresses then you absolutely must set a Sender: address to indicate who physically sent the message.

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// Set a single From: address
$message->setFrom('your@address.tld');

// Set a From: address including a name
$message->setFrom(array('your@address.tld' => 'Your Name'));

// Set multiple From: addresses if multiple people wrote the email
$message->setFrom(array(
  'person1@example.org' => 'Sender One',
  'person2@example.org' => 'Sender Two'
));

Setting the Sender: Address

A Sender: address specifies who sent the message and is set with the setSender() method of the message.

To set the Sender: address:

  • Call the setSender() method on the Message.

The Sender: address is visible in the message headers and will be seen by the recipients.

This address will be used as the Return-Path: unless otherwise specified.

Note

If you set multiple From: addresses then you absolutely must set a Sender: address to indicate who physically sent the message.

You must not set more than one sender address on a message because it's not possible for more than one person to send a single message.

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$message->setSender('your@address.tld');

Setting the Return-Path: (Bounce) Address

The Return-Path: address specifies where bounce notifications should be sent and is set with the setReturnPath() method of the message.

You can only have one Return-Path: and it must not include a personal name.

To set the Return-Path: address:

  • Call the setReturnPath() method on the Message.

Bounce notifications will be sent to this address.

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$message->setReturnPath('bounces@address.tld');

Signed/Encrypted Message

To increase the integrity/security of a message it is possible to sign and/or encrypt an message using one or multiple signers.

S/MIME

S/MIME can sign and/or encrypt a message using the OpenSSL extension.

When signing a message, the signer creates a signature of the entire content of the message (including attachments).

The certificate and private key must be PEM encoded, and can be either created using for example OpenSSL or obtained at an official Certificate Authority (CA).

The recipient must have the CA certificate in the list of trusted issuers in order to verify the signature.

Make sure the certificate supports emailProtection.

When using OpenSSL this can done by the including the -addtrust emailProtection parameter when creating the certificate.

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$message = Swift_Message::newInstance();

$smimeSigner = Swift_Signers_SMimeSigner::newInstance();
$smimeSigner->setSignCertificate('/path/to/certificate.pem', '/path/to/private-key.pem');
$message->attachSigner($smimeSigner);

When the private key is secured using a passphrase use the following instead.

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$message = Swift_Message::newInstance();

$smimeSigner = Swift_Signers_SMimeSigner::newInstance();
$smimeSigner->setSignCertificate('/path/to/certificate.pem', array('/path/to/private-key.pem', 'passphrase'));
$message->attachSigner($smimeSigner);

By default the signature is added as attachment, making the message still readable for mailing agents not supporting signed messages.

Storing the message as binary is also possible but not recommended.

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$smimeSigner->setSignCertificate('/path/to/certificate.pem', '/path/to/private-key.pem', PKCS7_BINARY);

When encrypting the message (also known as enveloping), the entire message (including attachments) is encrypted using a certificate, and the recipient can then decrypt the message using corresponding private key.

Encrypting ensures nobody can read the contents of the message without the private key.

Normally the recipient provides a certificate for encrypting and keeping the decryption key private.

Using both signing and encrypting is also possible.

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$message = Swift_Message::newInstance();

$smimeSigner = Swift_Signers_SMimeSigner::newInstance();
$smimeSigner->setSignCertificate('/path/to/sign-certificate.pem', '/path/to/private-key.pem');
$smimeSigner->setEncryptCertificate('/path/to/encrypt-certificate.pem');
$message->attachSigner($smimeSigner);

The used encryption cipher can be set as the second parameter of setEncryptCertificate()

See http://php.net/manual/openssl.ciphers for a list of supported ciphers.

By default the message is first signed and then encrypted, this can be changed by adding.

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$smimeSigner->setSignThenEncrypt(false);

Changing this is not recommended as most mail agents don't support this none-standard way.

Only when having trouble with sign then encrypt method, this should be changed.

Requesting a Read Receipt

It is possible to request a read-receipt to be sent to an address when the email is opened. To request a read receipt set the address with setReadReceiptTo().

To request a read receipt:

  • Set the address you want the receipt to be sent to with the setReadReceiptTo() method on the Message.

When the email is opened, if the mail client supports it a notification will be sent to this address.

Note

Read receipts won't work for the majority of recipients since many mail clients auto-disable them. Those clients that will send a read receipt will make the user aware that one has been requested.

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$message->setReadReceiptTo('your@address.tld');

Setting the Character Set

The character set of the message (and it's MIME parts) is set with the setCharset() method. You can also change the global default of UTF-8 by working with the Swift_Preferences class.

Swift Mailer will default to the UTF-8 character set unless otherwise overridden. UTF-8 will work in most instances since it includes all of the standard US keyboard characters in addition to most international characters.

It is absolutely vital however that you know what character set your message (or it's MIME parts) are written in otherwise your message may be received completely garbled.

There are two places in Swift Mailer where you can change the character set:

  • In the Swift_Preferences class
  • On each individual message and/or MIME part

To set the character set of your Message:

  • Change the global UTF-8 setting by calling Swift_Preferences::setCharset(); or

  • Call the setCharset() method on the message or the MIME part.

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    // Approach 1: Change the global setting (suggested)
    Swift_Preferences::getInstance()->setCharset('iso-8859-2');
    
    // Approach 2: Call the setCharset() method of the message
    $message = Swift_Message::newInstance()
      ->setCharset('iso-8859-2');
    
    // Approach 3: Specify the charset when setting the body
    $message->setBody('My body', 'text/html', 'iso-8859-2');
    
    // Approach 4: Specify the charset for each part added
    $message->addPart('My part', 'text/plain', 'iso-8859-2');
    

Setting the Line Length

The length of lines in a message can be changed by using the setMaxLineLength() method on the message. It should be kept to less than 1000 characters.

Swift Mailer defaults to using 78 characters per line in a message. This is done for historical reasons and so that the message can be easily viewed in plain-text terminals.

To change the maximum length of lines in your Message:

  • Call the setMaxLineLength() method on the Message.

Lines that are longer than the line length specified will be wrapped between words.

Note

You should never set a maximum length longer than 1000 characters according to RFC 2822. Doing so could have unspecified side-effects such as truncating parts of your message when it is transported between SMTP servers.

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$message->setMaxLineLength(1000);

Setting the Message Priority

You can change the priority of the message with setPriority(). Setting the priority will not change the way your email is sent -- it is purely an indicative setting for the recipient.

The priority of a message is an indication to the recipient what significance it has. Swift Mailer allows you to set the priority by calling the setPriority method. This method takes an integer value between 1 and 5:

  • Highest
  • High
  • Normal
  • Low
  • Lowest

To set the message priority:

  • Set the priority as an integer between 1 and 5 with the setPriority() method on the Message.
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// Indicate "High" priority
$message->setPriority(2);

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