📚 Book Explorer App

An Android app built with Jetpack Compose that lets you explore books using the Google Books API / OpenLibrary API.
This project is designed to practice and demonstrate modern Android development concepts like MVVM, Clean Architecture, Hilt, Flows, RoomDB, Paging 3, Navigation, and Unit Testing.

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✅ Build & Quality Status

This repository enforces static analysis (Detekt) and unit test coverage checks using GitHub Actions.

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📸 Screenshots

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✨ Features

• 🔎 Search books by keywords
• 📖 View detailed book information (title, author, description, cover image)
• ❤️ Save books to favorites/readList (stored locally with RoomDB)
• 📑 Pagination with infinite scroll using Paging 3
• 👤 Simple profile screen

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🛠️ Tech Stack

• UI: Jetpack Compose (Material 3, Navigation Compose)
• Architecture: MVVM + Clean Architecture
• Asynchronous: Kotlin Coroutines, Flow
• Dependency Injection: Hilt
• Networking: Retrofit + OkHttp
• Local Storage: Room Database
• Pagination: Paging 3
• Testing: JUnit, MockK, Turbine
• Static Analysis: Detekt

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🏗️ Project Structure

com.alpha.books_explorer/ 
│ 
├── data/                           # Data Layer (API + DB) 
│   ├── local/                      # Room database 
│   │   ├── converters/ 
│   │   │   ├── Converters.kt 
│   │   ├── dao/ 
│   │   │   ├── FavBookDao.kt 
│   │   │   ├── ReadingList.kt 
│   │   ├── entities/ 
│   │   │   ├── BookEntity.kt 
│   │   │   ├── ReadingListEntity.kt 
│   │   └── FavBookDatabase.kt 
│   │ 
│   ├── paging/  
│   │   ├── BooksPagingSource.kt 
│   ├── remote/                     # Retrofit API 
│   │   ├── BookApiService.kt 
│   │   └── dto/ 
│   │       ├── BookSearchResponse.kt 
│   │ 
│   ├── repository/                 # Repository implementation 
│   │   └── BookRepositoryImpl.kt 
│   │ 
│   └── mappers/                    # DTO ↔ Entity ↔ Domain 
│       ├── BookMapper.kt 
│ 
├── domain/                         # Domain Layer (business logic) 
│   ├── model/ 
│   │   ├── Book.kt 
│   │ 
│   ├── repository/                 # Abstract repository interfaces 
│   │   └── BookRepository.kt 
│   │ 
│   └── usecase/                    # Use cases 
│       ├── GetBooksUseCase.kt 
│       ├── SearchBooksUseCase.kt 
│       ├── GetBookDetailsUseCase.kt 
│       ├── SaveFavoriteBookUseCase.kt 
│       └── GetFavoriteBooksUseCase.kt 
│ 
├── di/                             # Dependency Injection (Hilt) 
│   ├── LocalDbModule.kt 
│   ├── NetworkModule.kt 
│ 
├── presentation/                   # Presentation Layer 
│   ├── ui/                         # Compose UI 
│   │   ├── home/ 
│   │   │   ├── HomeScreen.kt 
│   │   │   ├── HomeViewModel.kt 
│   │   │   └── HomeUiState.kt 
│   │   ├── search/ 
│   │   │   ├── SearchScreen.kt 
│   │   │   ├── SearchViewModel.kt 
│   │   │   └── SearchUiState.kt 
│   │   ├── details/ 
│   │   │   ├── BookDetailScreen.kt 
│   │   │   ├── BookDetailViewModel.kt 
│   │   │   └── BookDetailUiState.kt 
│   │   ├── favorites/ 
│   │   │   ├── FavoritesScreen.kt 
│   │   │   ├── FavoritesViewModel.kt 
│   │   │   └── FavoritesUiState.kt 
│   │   └── profile/ 
│   │       ├── ProfileScreen.kt 
│   │       ├── ProfileViewModel.kt 
│   │       └── ProfileUiState.kt 
│   │ 
│   │ 
│   └── navigation/ 
│       └── NavGraph.kt 
│ 
├── common/                         # Common utilities & helpers 
│   ├── constants/ 
│   │   └── ApiConstants.kt 
│   ├── utils/ 
│   │   ├── NetworkResult.kt        # Sealed class for Success/Error/Loading 
│   │   ├── Extensions.kt           # Common extension functions 
│   │   └── DispatcherProvider.kt   # For coroutines testability 
│ 
├── MainActivity.kt                  # Host Compose + Navigation 
└── BooksExplorerApplication.kt               # Application class (Hilt)  

🔌 API Reference

• Google Books API → https://developers.google.com/books/docs/v1/using

  Example request: https://www.googleapis.com/books/v1/volumes?q=android

📚 Learning Purpose

This app was built to cover:

• Jetpack Compose UI + Navigation
• RoomDB
• Coroutines + Flows
• Hilt Dependency Injection
• MVVM + Clean Architecture
• Retrofit Networking
• Paging 3
• Writing Unit Tests + enforcing coverage thresholds
• Enforcing code quality with Detekt

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👨‍💻 Author

Shubham Gadekar

• GitHub: shubhamgadekar