Code Organization in Large AngularJS and JavaScript Applications | Hacker News Reader

Code Organization in Large AngularJS and JavaScript Applications

cliffmeyers.com

92 pointsjoelhooks23 comments

I was surprised at Angular-seed's directory structure. It is fine for toy apps, but that isn't what it is really being billed as.

I'm building a django/angular app. Each django app gets its own angular module, and each angular module roughly shares the seed structure, but may be broken into more files (much like the second example in TFA). So my whole structure looks something like:

  django-project/
    app1/
      views.py
      static/
        coffeescript/
          app1.coffee #defines the module
          app1/
            directives.coffee
            controllers/
              foobaz_controller.coffee
        ...

The only thing I'm not keen on is the duplication of "app1" in the directory structure. It is done to prevent conflicts when static files are collected, but is redundant during development.

Thinking through this, I might be able to build a static files finder that looks for an angular directory in the django app and puts it in the right place. I'll have to think about that, since there are a lot of moving pieces with pipeline, et al, involved in the chain.

I recently completed my struggle with AngularJS/Django and the asset pipeline. I was using django-compressor but that was really not pleasant. What I did was completely decouple my AngularJS app from my Django app. I stopped using Django's collectstatic as well, and now use Grunt to compile my assets into a temporary "static" directory (not stored in version control), from an "assets" directory (stored in version control). I then use a fabric task to upload the contents of "static" to S3, to new directory with an incremented build number (something like s3://my-bucket/dist/v1234/). Once that is done, I update STATIC_URL in my Django app to reflect the new dist path.

My one tip: forget about using Django to manage your assets if you need cache-busting... use fabric and something like grunt.

This has always been a pet peeve of mine with projects like rails. Usually when I work on a piece of the system I'll be working on a single component, be it user, product, report or whatever. That means I will either have a bunch of different directory trees open in my IDE (Which can be bigger than a screen for large projects), or I will be using some quick-open tool (Which still is great when you know what you want, but less so when you just want to get a quick overview of a component).

God forbid I try to edit multiple components at a time, and forget browsing my repo on github. Organization like this would make life so much easier in so many ways.

A nice example of a slightly larger AngularJS app can be seen here: https://github.com/angular-app/angular-app

Say, that is a good example!

I find the general layout suggested for Angular apps to be a bit weird. There are prominent articles by Angular devs that suggest splitting things into services, models etc. I guess it just follows the familiar pattern that Rails etc give you.

I've recently built a couple of large(ish) python web apps. I use Flask for the web frontend but instead of starting with Flask I built all the libraries / core code first and then use Flask to tap into that. It makes for a much better application structure. Instead of thinking about how you should be splitting into blueprints you really think about the application structure as a whole (and you remove dependencies on the framework). I'm _much_ happier with the results.

I'm refactoring the Angular frontend at the moment so the example you've pointed to is a timely piece of code for me to skim. Thanks!

That's just the tip of the iceberg. Many complicated projects have landing page which should not include the whole javascript app, but still need the same collections & models. Or for example website with CMS will include administration part which is fairly different in structure.

My applications are backbone based and my directory structure is similar to :

   scripts/
     classes/
       collections/
         socket.coffee
       ui/
         popup.coffee
       page.coffee
     models/
       user.coffee
     collections/
       items.coffee
       products.coffee
     ui/
       navigation/
         top.coffee
         sidebar.coffee
       overlay.coffee
     pages/
       landing/
         home.coffee
         about.coffee
       cms/
         home.coffee
         admin.coffee
     utils/
       templates.coffee
     landing.coffee
     cms.coffe

What's important in my app is classes path. I put there only reusable classes, and using coffeescript I can simply extend the whole module by

   class Items extend require('classes/collections/socket.coffee')

   module.exports = new Items()

Also I always use utils folder, for general javascript helper functions.

What's in these files?

  models/
    CartModel.js
    ProductModel.js
    SearchResultsModel.js
    UserModel.js

I have a lot of controllers, directives, filters and services which sit fine in their own files/modules but I don't understand what I would put in a model file.

Model files in angularJS are often basic wrappers around either $ressource or $http. From that you can add default values, collection-like functions, etc.

Do you happen to have a link to an example for those of us just getting started in Angular?

I think typically people start them out in 'services.js' since effectively models in angular are constructors that are created, and then injected whenever you need a certain type (so you have a service that returns the constructor function).

A good example of this is how the tutorial treats the restful 'Phone' resource, creating a service that injects the resource where necessary. I've started calling them 'models' rather than 'services' internally as well, so it's interesting to me that others are too.

http://docs.angularjs.org/tutorial/step_11

The Model files are storing state, essentially. In this case they are following a pattern from Robotlegs (as3). I wrote it up here http://joelhooks.com/2011/03/12/an-introduction-to-robotlegs...

These are then injected as "services" in your controllers.

I'm building a rails+angular app at the moment, and sort of fell by default in the component-type folders. Reading this blog makes me think that you're right and topical folders are much better, but then an alarm bell goes off. If this is a good way of doing it, why isn't it the Rails way of doing it?

Does anyone know if the Rails core team ever discussed using this directory layout? I know that it would take a fairly big rewrite of some glue logic in Rails that we all know and love, but merely 'hard to do' often does not stand in the way of 'the right way' in Rails.. right?

Can anyone point out something that immediately stands out as possibly problematic?

I thought the same thing.

In my minds eye I don't see a nice place to stuff views. Module specific ones could live inside the module but Rails has layouts and also typically has shared views.

Sinatra would be a good framework to play around with this structure.

This reminds me of the beginning of Bob Martin's keynote[0] at Ruby Midwest 2011[1]. I don't agree with everything he said, but the code organization point is sound.

[0] http://www.youtube.com/watch?v=WpkDN78P884&t=6m39s

[1] http://www.confreaks.com/events/rubymidwest2011

I'm not sure I agree with the idea of adding utility methods to the $rootScope to avoid wiring in dependencies repeatedly. I would probably go with defining a utility class and indeed injecting it into every controller that needs it. I like the idea of having my utility methods clearly defined in one place. Any opinions here on the pros/cons?

I'm for using services to define whatever object used across controllers and other services. Using rootscope or scope inheritance is very tricky in AngularJS

Agreed. Any utility functions should go into a different service.

Using $rootScope feels like a hack.

Much thanks for the write up! I'm currently pitting together my first Angular app and feel much more confident in a design decisions that I've made so far.

Body text is really light making it hard to read, at least on my eyes. The content seems interesting though.

Thanks for the feedback. I made the text darker.

If you're in the mood for constructive feedback, there's something that makes that page difficult to read. It could just be font rendering at that tiny size, it could be the contrast with the line spacing given the text size. Either way, taking the font-size up to 15px makes it readable, for me.

It's also a good idea to use font-size:100% let the browser/user decide what font size to use , yours is a bit small. It should not break your layout. nice article.

Thanks, I'll look at adjusting the base font size as well. I agree it's a tad small.

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