JST Handlebars templates

README.md

I really struggled to get this working. I initially found https://gist.github.com/1990736 but it wasn't working for me, so I decided to throw it out, copy the original JST task and adapt it.

The jsthb helper has been lifted entirely from https://gist.github.com/1990736, the rest I've hacked at myself. This has been tested with both ajax loading and a release build.

fetchTemplate.js

fetchTemplate: function(path, done) {
      var JST = window.JST = window.JST || {};
      var def = new $.Deferred();

      // Should be an instant synchronous way of getting the template, if it
      // exists in the JST object.
      if (JST[path]) {
        if (_.isFunction(done)) {
          done(JST[path]);
        }

        return def.resolve(JST[path]);
      }

      // Fetch it asynchronously if not available from JST, ensure that
      // template requests are never cached and prevent global ajax event
      // handlers from firing.
      $.ajax({
        url: path,
        type: "get",
        dataType: "text",
        cache: false,
        global: false,

        success: function(contents) {
          JST[path] = Handlebars.compile(contents);

          // Set the global JST cache and return the template
          if (_.isFunction(done)) {
            done(JST[path]);
          }

          // Resolve the template deferred
          def.resolve(JST[path]);
        }
      }

jsthb.js

/*
 *
 * Task: jsthb
 * Description: Compile Handlebars templates to JST file
 * Contributor(s): @mheap
 *
 */

module.exports = function(grunt) {

  var file = grunt.file,
       log = grunt.log;

  var _ = grunt.utils._;

  grunt.registerMultiTask("jsthb",
    "Compile underscore templates to JST file", function() {

    var options = grunt.config("jsthb", this),
      namespace = options.namespace || "JST",
       settings = options.templateSettings || null,
          files = file.expand(this.data);

    // Create JST file.
    file.write(this.target, grunt.helper("jsthb", files, namespace, settings));

    // Fail task if errors were logged.
    if (grunt.errors) { return false; }

    // Otherwise, print a success message.
    log.writeln("File \"" + this.target + "\" created.");
  });

  grunt.registerHelper("jsthb", function(files, namespace, templateSettings) {
    // Ensure we get the underscore from the node_modules folder
  var Handlebars = require("handlebars");

  // Comes out looking like this["JST"] = this["JST"] || {};
  var contents = "(function() {\n  var template = Handlebars.template, templates = Handlebars.templates = Handlebars.templates || {};\n";

  // Compile the template and get the function source
  contents += files ? files.map(function(filepath) {
    var templateFunction = 'templates[\'' + filepath + '\'] = template(' + Handlebars.precompile(file.read(filepath)) + ');\n';

    return templateFunction;
  }).join("\n\n") : "";

  return contents + "})();";
  });

};