Take the 2-minute tour ×
Stack Overflow is a question and answer site for professional and enthusiast programmers. It's 100% free, no registration required.

Thanks to the great article from Dan Wahlin, I managed to implement lazy loading of Angular's controllers and services. However, there does not seem to be a clean way to lazy load independent modules.

To better explain my question, assume that I have an app would be structure as below without RequireJS:

// Create independent module 'dataServices' module with 'Pictures' object
angular.module("dataServices", []).factory("Pictures", function (...) {...});

// Create 'webapp' ng-app, with dependency to 'dataServices', defining controllers
angular.module("webapp", ['dataServices'])
.controller("View1Controller", function (...) {...})
.controller("View2Controller", function (...) {...});

Here is the sample app with RequireJS in Plunker:
http://plnkr.co/aiarzVpMJchYPjFRrkwn

The core of the problem is that Angular does not allow adding dependency to ng-app post instantiation. As result, my solution is to use angular.injector to retrieve the instance of Picture object to be used in my View2Controller. See js/scripts/controllers/ctrl2.js file.

This creates 2 problems for me:

  1. The injected services runs outside of angular and therefore all async call must end with $scope.$apply()
  2. Messy code where some object can be injected using standard angular syntax while others require the explicit use of injector.

Have any of you figured out how to lazy load independent module using RequireJS and somehow hook this module in angular so normal angular dependency injection syntax can be used?

Note:
The question is on lazy loading of independent module. One simple solution to this specific example is to create "Pictures" object using cached $providers during ng-app.config but that is not what I am looking for. I am looking for solution that works with 3rd party module such as angular-resource.

share|improve this question

2 Answers 2

up vote 6 down vote accepted

Take a look at my project in GitHub: angular-require-lazy

This project is intended to demonstrate an idea and motivate discussions. But is does what you want (check expenses-view.js, it loads ng-grid lazily).

I am very interested in comments, ideas etc.


(EDIT) The ng-grid Angular module is lazy loaded as follows:

  1. expenses-view.js is loaded lazily, when the /expenses route is activated
  2. expenses-view.js specifies ng-grid as a dependency, so RequireJs loads ng-grid first
  3. ng-grid is the one that calls angular.module(...)

In order to accomplish this, I replaced (proxied actually) the real angular.module method with my own, that supports laziness. See bootstrap.js and route-config.js (the functions initLazyModules() and callRunBlocks()).

This implementation has its drawbacks that you should be aware of:

  1. Config functions are not implemented (yet). I do not know if it is possible to lazily provide config-time dependencies.
  2. Order matters in definitions. If service A depends on B but A is defined after B in your module, DI wil fail. This is because the lazyAngular proxy executes definitions immediately, unlike real Angular that makes sure dependencies are resolved before executing the definitions.
share|improve this answer
    
Interesting implementation but it does not really answer my question on lazy loading of "angular.module", unless I am missing something. None of your expenses-view.js' dependencies are coded using "angular.module". But I will keep this in mind for what I am trying to do. –  marcoseu Oct 2 '13 at 10:37
    
Maybe the edit explains things a bit better. –  Nikos Paraskevopoulos Oct 2 '13 at 10:55
    
I copied your code in bootstrap.js, more specifically everything related to makeLazyModule and lazyAngular.module and it actually works. Now, if I only understood why it is working... –  marcoseu Oct 2 '13 at 16:16
    
Took me a while but I think I finally got it. You created a proxy version of angular.module that calls the cached $provider during ng-app.config for lazy loaded modules. Brilliant!!! –  marcoseu Oct 2 '13 at 19:52
    
@marcoseu Hi, thanks for the kudos; please take a look at the drawbacks of my solution, added to the answer! –  Nikos Paraskevopoulos Oct 3 '13 at 14:33

I finalized my own implementation called angularAMD and here is the sample site that uses it:

http://marcoslin.github.io/angularAMD/

It handles config functions and out of order module definitions.

Hopefully this can help other looking for something to help them with RequireJS and AngularJS integration.

share|improve this answer
    
Hi i am trying to implement angularAMD. Does using it have to follow your folder structure?? I want to include the services and directives if they are in different folders? Can i do that? –  VishwaKumar Mar 3 at 13:23
    
@VishwaKumar no, you do not need to follow my folder structure at all. It is all relative to baseUrl in your main.js. –  marcoseu Mar 3 at 14:14

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.