Subject

The SmtpRequest JavaScript class has been introduced with version 0.9.21 of the Presentation Engine. The class is fairly simple to use and is similar to the existing HttpRequest class. The class provides complete control of email generation including the ability to create multipart emails (for example to include attachments or to include a rich text HTML variant of an email).

The class encapsulates and abstracts the standard interface to an SMTP server. The formal class specification is available as the SmtpRequest JavaScript class.

Previous version of the Whitebeam system have included basic access to email via the Message Template. The advantages of this new mechanism include:

• Unlimited message size.
• Ability to control the SMTP headers, including the Content-Type, allowing generation of rich text 'newsletter' emails.
• Support for 'multipar/*' content type allowing the creation of emails with attachements.

SmtpRequest fields in more detail

The SmtpRequest is controlled by the properties the client sets on the object before invoking the 'send' method. The properties on the object are described as follows:

The 'msg.body' parameter provides the body of the email message provided the 'rawData' flag is absent or set to false. The object may be either:

• A single object or an array of exactly one object, in which case a 'standard' single part message is generated or
• It is an array with >1 element in which case a multipart message is created, with each array element representing a different part.

Single Part

The 'msg.body' property is a single object or an Array object with one entry. The proprties should either be a string object or a Binary object. The properties are:

Multiple Part

More interesting condition is the multipart encoding. This is triggered if the 'msg.body' is an array that contains MORE THAN 1 element. In this case each entry in the array is treated in the following way:

Nested Multi-part

This is a recent enhancements to the SmtpRequest object and only available in Whitebeam release 1.1.3 and above.

Nested multi-part enables complex emails to be constructed that can support, for example, emails with embedded images.

Nested multi-part is a simple extension of multi-part. In this case one of the entries in the 'body' array is itself an array. This can best be illustrated by an example structure. In the following the two top-level body components are a plain text 'thing' and then a collection of things (HTML and images) that make up the main message :

  var msg = new SmptRequest;

  var plainText = new String('This is a plain text message');

  // The HTML part is incomplete!
  var html = [
    // Note must be a string object - not a literal!
    new String('<h1>Message</h1> <p><img src="cid:000000123">')
  ];

  // Load the image and add it to the HTML part
  var img = new Binary;
  img.load('/images/img.gif');

  html.push(img);

  // Set appropriate header/encoding information
  plainText.contentType = 'text/plain';
  plainText.quotedPrintable = true;
  plainText.headers = {'Content-Transfer-Encoding':'quoted-printable'};

  html[0].contentType = 'text/html';
  html[0].quotedPrintable = true;
  html[0].headers = {'Content-Transfer-Encoding':'quoted-printable'};

  html[1].contentType = 'image/gif';
  html[1].headers = {
    'Content-ID':'000000123'
    'Content-Disposition':'inline;\n\tfilename="img.gif"',
  };

  html.multipart = 'related';

  msg.body = [plainText, html];
  msg.to = 'xxxxx@yyyyyy.zz';
  msg.send();