Merrick Christensen - JavaScript Dependency Injection

Merrick Christensen - JavaScript Dependency Injection

var WelcomeController = function (Greeter) {
    document.write(Greeter.greet());
};

var Injector = {

    dependencies: {},

    process: function(target) {
        console.log('target:', target)
        var FN_ARGS = /^function\s*[^\(]*\(\s*([^\)]*)\)/m;
        var text = target.toString();
        console.log('target.toString():',text)
        var args = text.match(FN_ARGS)[1].split(',');
        console.log('args:', args);
        console.log('this.getDependencies(args):', this.getDependencies(args));

        target.apply(target, this.getDependencies(args));
    },

    getDependencies: function(arr) {
      console.log('fn: getDependencies', arr);
        var self = this;
        return arr.map(function(value) {

            return self.dependencies[value];
        });
    },

    register: function(name, dependency) {
        this.dependencies[name] = dependency;
        console.log('fn:register', this.dependencies)
    }

};

var RobotGreeter = {
  greet: function() {
    return 'Domo Arigato';
  }
};

var OtherGreeter = {
    greet: function() {
      return 'That will do pig.';
    }
};

// Randomly register a different greeter to show that WelcomeController is truly dynamic.
Injector.register('Greeter', Math.random() > 0.5 ? RobotGreeter : OtherGreeter);

Injector.process(WelcomeController);