Architectural solution explanation - LevNovikov92/movie-database GitHub Wiki

Overview

Project architecture was developed for the big scalable project and working in a large team.

1. Structure

The project is using multi-module structure to separate code by logical meaning, stability and keep explicit dependencies between components. Additionally, we can specify module owners to make changes more safety and make the code more maintainable.

Different module levels introducing strict limits for dependencies and help to avoid wrong architectural solutions, cyclic dependencies and build time increasing, that is very important for big projects.

Module-levels, purpose and dependencies restrictions specified in gradle.settings. Current module tree picture is provided on this image

2. Dependency injection

Two types of DI components are used in the current project: explicit dependency (Dagger components) and implicit dependency (Dagger subcomponents).

Component injection is used to connect modules (like app and feature-movies_list). This will help to see clearly what kind of dependencies module have and provide an interface for a parent to resolve (for instance MainComponentDependencies). It will help to control dependency changing. Additionally, this solution will help to improve build time since subcomponents injection will take more time to compile if it is used for the whole app. The incremental build will also be improved because components are separated explicitly. Subcomponents tree will be recompiled every time.

Inside the module, subcomponents are used. It will not affect build time, will reduce boilerplate and simplify development.

3. UI layer architecture

For learning purpose in a project are used two patterns: MVP and MVVM. feature-movies_list following MVP pattern. feature-movie_details following MVVM pattern with dataBinding usage.

feature-movies_list UI was split into two views in order to keep two independent axes of changes. That will help to make UI more flexible.