AngularJS Project Structure Tutorial

Elliot Forbes ⏰ 4 Minutes 📅 Apr 9, 2017

Project organization is important for all angularjs applications. Having a well defined and easy to traverse project structure can be hugely beneficial further down the line when you have to deal with maintenance and enhancements.

I’m going to start off by showing you sub-optimal project structures and then move on to the most recommended way of structuring your angularjs projects.

Simple PoCs and Tiny Applications

There are multiple ways we can structure applications and of course different structures are better suited for different applications. For incredibly simple PoCs and technical demos then you might be better suited to a flat structure that looks like so:

Project Structure
-- index.html
-- app.js
-- angular.min.js
-- controller.js
-- service.js

But this structure, if the app grows, becomes ungainly and your app.js, controller.js and service.js become packed with thousands of lines of code.

Pro/Con Justification
Pro incredibly quick and easy to put together
Pro good for initial PoCs
Con As soon as your application grows this becomes a mess
Con Having one file for controllers and services could lead to a haystack of code

File Type Based Approach

Another well known way of structuring applications is to split applications up based on file type. This leads to a project structure like this:

Project Structure
-- controllers
-- services
-- routes
-- directives
-- index.html
-- app.js

Now whilst this may seem to offer a nice structure, it essentially leaves you jumping around the project when adding a new feature to your application. Code for one piece of functionality is spread across multiple directories and as soon as your application grows, you’ll suddenly have a haystack of controllers to wade through.

Pro/Con Justification
Pro features a more structured approach than the flat structure featured above
Pro Good for small-medium sized applications where number of files won’t grow into a haystack
Con Code for each feature is split across multiple directories
Con As soon as you hit more than 10 or so of a file type, it becomes a haystack

Component Based Approach

A new style of structuring your application is to follow a component based approach. This makes sense as we can break our applications down into a series of components and sub-components.

This gives us a number of benefits including easy extendability and maintainability. Take for instance a very simple website admin application, the file structure for that if broken into components could look something like so:

Project Structure
-- libs/
-- src/
---- assets/
---- common/
------ top-nav/
-------- top-nav.html
---- components/
------ articles/
-------- articles-edit/
-------- articles-new/
-------- articles-all/
-------- article.routes.js
-------- article.component.js
-------- article.service.js
---- app.js
---- app.routes.js
---- index.html

Notice how within our articles directory we have multiple sub-directories such as articles-edit And articles-new which would in theory contain all our code for creating new articles and editing them.

Now imagine we wanted to add a comments section that showed us all the new comments on our site. We could easily extend this structure by adding a comments/ directory underneath our components/ directory. This comments/ subdirectory would encapsulate all our comments related code.

Pro/Con Justification
Pro Applications can be broken down into an unlimited number of sub-components
Pro Easy to extend and add new components that fit into project structure
Pro Easy to maintain, all structure for a component is grouped under one directory
Pro Parallel development becomes easier
Con Interaction between components may be challenging to implement

Examples of Component Based Applications

For examples of how to write your own component based applications then please check out my post: Working with Component Based AngularJS Projects.

Todd Motto, one of the most respected AngularJS community members has an excellent github repo that showcases a component based application : Angular 1.5 Components App

Conclusion

If you found this tutorial or have any further questions then please let me know in the comments section below.