BlazorBuddy is a real-time collaborative study companion application built with Blazor Server and .NET 10. Users can write and categorize markdown notes, chat with other users and sketch on a canvas.

• .NET 10.0 SDK
• SQL Server LocalDB (optional, for default dev config)

This project uses Git Submodules. You must clone recursively or initialize submodules after cloning.

git clone --recursive https://github.com/n4sser77/blazor-buddy.git

If you already cloned without the submodules You can run the command below to get and update the submodules

git clone https://github.com/n4sser77/blazor-buddy.git
cd blazor-buddy
git submodule update --init --recursive

Run the application:

dotnet run --project BlazorBuddy.WebApp

By default, the app uses (localdb)\mssqllocaldb. Ensure you have it installed or update appsettings.json with your connection string.

Open your browser and navigate to https://localhost:7000 (or the port shown in the terminal).

The solution includes integration tests that verify the application flow using an in-memory database.

Run the tests:

   dotnet test

The application follows a Monolithic Layered Architecture using Blazor Server for the presentation layer.

• BlazorBuddy.Core: Contains the domain entities (Models) and shared logic. This layer has no dependencies on the UI or Data Access layers, ensuring high cohesion for domain logic.
• BlazorBuddy.WebApp: The main entry point. It hosts the Blazor Server application, manages Dependency Injection, and handles HTTP requests.
  • Components: Razor components for the UI.
  • Services: Business logic layer (e.g., ChatService, NotesStateService).
  • Repositories: Data access layer using Entity Framework Core.
• BlazorBuddy.Test: Integration tests project.

• Blazor Server: Chosen for its ability to build rich, interactive UIs with C# without needing a separate frontend framework. It maintains a real-time connection via SignalR.
• Dependency Injection (DI): Extensively used to decouple components from concrete implementations. Interfaces (e.g., INoteRepo, IChatService) are injected, promoting loose coupling and testability.
• State Management:
  • Singleton Services: Used for global state or caching (e.g., NotesStateService for caching notes, ChatEventBroker for broadcasting messages).
  • Scoped Services: Used for per-request/per-circuit operations (e.g., Repositories).
• Entity Framework Core: Used for ORM. The app is configured to use SQL Server in production/development and InMemory database for Integration Tests.

• Cohesion: The project is structured to keep related functionality together. Services handle business rules, while Repositories strictly handle data persistence. Core is pure domain.
• Coupling: Low coupling is achieved through the use of Interfaces. The WebApp depends on abstractions rather than concrete implementations where possible, allowing for easier unit testing and maintenance.

The architecture is designed with testability in mind:

• Integration Tests: The BlazorBuddy.Test project uses WebApplicationFactory to spin up the app in-memory.

• Database Abstraction: The CustomWebApplicationFactory replaces the SQL Server provider with an InMemory database, allowing tests to run without external infrastructure dependencies.

• Service Isolation: Services can be unit tested by mocking their repository dependencies.

• Microsoft.AspNetCore.Identity.EntityFrameworkCore: For user authentication and management.
• Microsoft.EntityFrameworkCore.SqlServer: Database provider.
• PSC.Blazor.Components.MarkdownEditor: A Markdown editor component (included as a submodule).

BlazorBuddy/
 BlazorBuddy.Core/       # Domain Models (POCOs)
 BlazorBuddy.WebApp/     # Main Blazor Server Application
    Components/         # UI Components (Pages, Layouts)
    Services/           # Business Logic & State
    Repositories/       # Data Access (EF Core)
    Data/               # EF DbContext & Migrations
    Program.cs          # App Entry & DI Configuration
 BlazorBuddy.Test/       # Integration Tests
 Libs/                   # External Libraries (Submodules)