An example app that utilizes Github users API.

At 4/23, I've refactored the source code to use clean architecture. You can see the old implementation before refactoring here: https://github.com/lutfime/GithubList/tree/633937225f3e5def9ceede6d152f6fcf57058e8e

The commits has been done in smaller scale with description, you can follow the refactoring processes here. https://github.com/lutfime/GithubList/commits/master

Improvements of the implementation using clean architecture:

• Use of composition root to compose dependencies
• Use dependency injection for better components testability
• Use dependency inversion for APILoader and LocalLoader instead of using concrete infrastructure implementation. This makes the components more reusable and testable.
• Use adapter, decorator and composite patterns to compose different behaviour of LocalLoader, RemoteLoader and ImageLoader
• Move cross cutting concern such as threading and internet connection check from view model and view controller to composition root.
• Better separation of code
• Added more unit tests
• Added snapshot tests
• Use observer instead of delegate in view model for better readability
• Remove anti-pattern singleton usage
• Now view controller become more clean, only used for displaying UI instead of contains logic.

There are multiple improvements still can be done in the future

• Add more unit tests that tests each class components to work correctly
• Add acceptance tests that test the overall behaviour of the app. For example test when offline app load and render data from cache
• Separate User object to User and UserProfile so each UserList and UserProfile screens use either one only. By separating model objects, we can make the properties immutable which are more type safe.

Note: Composition root is not shown in the diagram as composition root uses have dependencies to most modules because composition root is a centralized place to compose the dependencies.