Templates

Introduction

There are many libraries that provides templates. Mustache is one of the best known.

It is fairly easy to roll your own template solution. You just need to traverse the DOM and replaces string with a specific prefix and suffix, for instance <<< and >>> with some other string.

code

Example of template solution:

<!DOCTYPE html>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
</head>
<body gz-templ-prefix='<<<' gz-templ-suffix='>>>'>
  <h1>A nice header</h1>
  <p id='1'>First paragraph. Here is a
    <strong>bold</strong> word in the middle of everything.</p>
  <p id='2'>Second paragraph</p>
  <p>English: <<<TEXT1.EN>>> </p>
  <p>Swedish: <<<TEXT1.SE>>> </p>

  <hr/>
  Open the console for more details.

  <script>
    // workaround since NodeList do not inherit Array (not for IE6/7/8)
    NodeList.prototype.forEach = Array.prototype.forEach;
    NamedNodeMap.prototype.forEach = Array.prototype.forEach;

    // Template definitions (typically multi-lingual)
    // ==============================================

    var texts = {};
    texts['TEXT1.EN'] = 'This is the first text string';
    texts['TEXT1.SE'] = 'Det här är den första text strängen';

    // Template logic
    // ==============

    var moduleSelf = this;

    var templPrefix = '<<<';
    var templSuffix = '>>>';

    var transformText = function (text) {
      var re = RegExp(templPrefix + '.*' + templSuffix);
      var found = text.match(re);
      if (!found) {
        return text;
      }

      found.forEach(function (str) {
        // strip out the 
        var index = str.substr(templPrefix.length,
          str.length - templPrefix.length -
          templSuffix.length);

        // do the reaplcement if there is one
        if (texts[index]) {
          text = text.replace(str, texts[index]);
        }

      })

      return text;
    };

    // Process one node in the DOM tree
    var processNode = function (node) {
      var str = 'Name: ' + node.nodeName + ', type: ' +
        node.nodeType;

      // process the text/value
      if (node.nodeValue) {
        str += ', value: ' + node.nodeValue;
        node.nodeValue = transformText(node.nodeValue);
      }

      // Process the children
      if (node.attributes) {
        node.attributes.forEach(function (attr) {
          if (attr.specified) {

            // The prefix and suffix for temapltes can be changed in the body
            if (node.nodeName === 'BODY' && attr.name === 'gz-templ-prefix') {
              templPrefix = attr.value;
            }

            if (node.nodeName === 'BODY' && attr.name === 'gz-templ-suffix') {
              templSuffix = attr.value;
            }

            str += ', name: ' + attr.name + ', value: ' + attr.value;
          }

        });
      }

      console.log(str);
    };

    var traverse = function (node) {

      if (node.nodeName !== 'SCRIPT' && node.nodeName !== 'HTML') {
        processNode(node);
      }

      if (node.nodeName === 'SCRIPT') {
        return;
      }

      node.childNodes.forEach(traverse);
    };

    document.addEventListener('DOMContentLoaded', function (e) {
      traverse(document.documentElement);
    });
  </script>
</body>
</html>