Counters Android App

Project using the latest Android APIs and best practices, using asynchronous communication with the local database and remote server.

Some notes

I am not the best UI/UX guy, so I tried to show my architecture, libraries and design pattern knowledge at most of the time.

Each of the features has its on branch and almost of them are mapped inside the issue Feature Roadmap. I followed the conventional commits messages.

The code coverage tool that I use (codecov.io) was not working properly, I couldn't see any coverage reports in the web app, so I tried to cover at least 80% of code looking on the basic report.

Running the Application

1. Clone repository
2. Start server

   $ cd server
   $ npm install
   $ npm start
   

3. Run Android project in Android Studio

Architecture Explanation

I choose to modularize just the project layers instead of the features because there were just two screens and there are no plans to add more. I focused on ease to maintain and on Clean Architecture principles.

This is a representation of the architecture, the connection between UseCases is not obligatory, more details below.

The arrows on the top can be read as "talks to".

:app

This is the presentation layer, it is responsible for what the user sees.

• Fragment: The Fragment is responsible to listen to the user inputs and its ViewModel outputs.
• ViewModel: It expects the Fragment inputs and calls the UseCases, from domain module, then, it can output the data to the Fragments via LiveData observers. All the ViewModels in this project also have a Navigator.
• Navigator: It navigates or pops to other fragments.

---

:domain

This is the domain layer, it holds the business rules of the applications and it is a pure java/kotlin module.

• UseCase: It is responsible for the business rules on the application, it talks to the repositories by dependency inversion or to another use cases.

---

:data

This is the data layer, it does not contain any business rules, it is responsible to get data from local or remote data sources.

• Repository: It is just a composition of local or remote data sources, the interfaces on those are from the domain module.
• DataSource: It is responsible to talk with the remote server or local database.

API Endpoints & Examples

GET /api/v1/counters
# []


PUT /api/v1/counters/sync
Request Body:
# {
#   "deletedCounterIds": [],
#   "counters": [
#     { "id": "-MZ-CFVG--8LbqVX2LaM", "title": "Cupcakes eaten", "count": 3 }
#   ]
# }

Response Body:
# [
#   { "id": "-MZ-CFVG--8LbqVX2LaM", "title": "Cupcakes eaten", "count": 3 }
# ]


PUT /api/v1/counters/sync
Request Body:
# {
#   "deletedCounterIds": [ "-MZ-CFVG--8LbqVX2LaM" ],
#   "counters": [
#     { "id": "-MZ-DTl7e7urGjlsAt3X", "title": "Tequila shots", "count": 30 }
#   ]
# }

Response Body:
# [
#   { "id": "-MZ-DTl7e7urGjlsAt3X", "title": "Tequila shots", "count": 30 }
# ]