Songly - Music Lovers App

Songly is an all-in-one application for music enthusiasts. It offers a complete experience with product listing, product cart, checkout, and detailed product information—all designed for music lovers.

Features

• Product Listing: Browse a wide variety of music products.
• Product Cart & Checkout: Easily add products to your cart and complete purchases.
• Product Details: View comprehensive details for each product.
• Data Caching: Loads products from the network initially, then caches them locally for faster subsequent access.
• Force Refresh: Pull-to-refresh functionality to manually update product listings.
• Advanced Navigation: Uses AutoRoute for flexible and intuitive routing.
• State Management: Follows the MVVM & Clean Architecture patterns using Bloc Cubit.
• Dependency Injection: Uses Injectable with GetIt for service location and dependency management.
• Multi-Module App: Organized as a multi-module app leveraging a monorepo setup managed by Melos.

Architecture & Modules

Module	Description
app	Presentation layer containing UI components, navigation, and view logic.
data	Data layer with repository implementations and data provider contracts for products.
domain	Business logic layer defining use cases and repository contracts, containing core business rules.
shared	Shared models and utilities (a lighter version of clean architecture) to reduce redundant data transformations.
config	Configuration module that leverages Flutter environment variables (using Dart defines and .env files) for secure configuration.
dependency_injection / dependency_registry	Provides common dependency injection contracts and wiring of all modules through advanced annotation-based coding and code generation.
localisation	Supports multi-language functionality (currently English).
network-retrofit	API data provider module that uses Retrofit (with Dio internally) for network calls.
database-realm	Local storage module using Realm, a NoSQL database for caching data.

Screenshots

Below are some screenshots showcasing the app's features:

Screenshot 1	Screenshot 2	Screenshot 3

Screenshot 4	Screenshot 5	Screenshot 6

Technology Stack

• Flutter: UI framework for building cross-platform applications.
• Bloc/Cubit: For state management, following MVVM & Clean Architecture principles.
• AutoRoute: For advanced navigation and routing.
• Injectable & GetIt: For dependency injection and service location.
• Dio & Retrofit: For making network API calls.
• Realm: For local data caching.
• Melos: For managing a multi-module monorepo.

Project Structure

Module	Description
app	Presentation layer (UI, Navigation, etc.)
data	Data layer (Repositories, Data Providers)
domain	Business Logic (Use Cases, Repository Contracts)
shared	Shared Models and Utilities
config	Environment configuration using Flutter environment variables
dependency_injection & dependency_registry	DI setup and module wiring
localisation	Multi-language support
network-retrofit	API Data Provider using Retrofit/Dio
database-realm	Local NoSQL database using Realm

Test Cases

The project includes a comprehensive suite of tests to ensure the reliability and consistency of the application. The tests are organized into three main categories:

Data Layer Tests

• Repository Tests:
  Verify that data is correctly fetched from the network and cached locally. These tests cover:

  • Successful data retrieval from both remote and local sources.
  • Handling error scenarios when fetching data.
  • Ensuring that caching mechanisms work as expected.

• API Provider & Local Storage Tests:
  Validate that the API providers and local database (Realm) components correctly parse and store data.

Domain Layer Tests

• Use Case Tests:
  Test the business logic and repository contracts defined in the domain module. For example:
  • Verifying that the FetchTrendingSongsUseCase correctly calls the repository with the appropriate parameters.
  • Ensuring that parameter validation (e.g., verifying positive limits) behaves correctly.

UI & Golden Tests

• Widget Tests:
  These tests confirm that the UI components (such as buttons, list items, and dashboards) behave correctly:

  • Correct rendering of text and icons.
  • Proper response to user interactions (e.g., tapping a button).

• Golden Tests:
  Golden tests perform visual regression testing by comparing the rendered output of UI components against pre-approved "golden" images. Key golden tests include:

  • Rendering of the AppButton and CartButton in different themes and states.
  • Ensuring that any visual changes are intentional.
    To run the golden tests and update the images if needed, use:

  flutter test --update-goldens
  

Navigation & Dependency Injection

Navigation:

The app uses AutoRoute for managing navigation between pages.

Dependency Injection:

Uses Injectable (backed by GetIt) to manage dependencies across modules. Each module has its own DI configuration.

Contributing

Contributions are welcome! Please open an issue or submit a pull request with your improvements or bug fixes.