🔧 Mechanical Workshop Management System

📖 Project Overview

The Mechanical Workshop Management System is designed to manage and organize workshop operations in a clean, scalable, and maintainable way. The project focuses heavily on Business Logic enforcement, clear separation of concerns, and modern backend architecture patterns.

The system helps manage:

• Customers and their Vehicles
• Repair Tasks and Parts need for workOrder
• Work Orders lifecycle and status transitions
• Labors / Employees assignments
• Authorization & Access Control based on roles and policies

The goal of the project is not just CRUD operations, but a real-world, production-ready architecture that reflects best practices.

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🏗️ Architecture

The project is built using:

✅ Clean Architecture

• Clear separation between Domain, Application, Infrastructure, and API layers
• Business rules are isolated from external frameworks
• High testability and maintainability

✅ CQRS Pattern (Command Query Responsibility Segregation)

• Commands for write operations
• Queries for read operations
• Improved scalability and clarity of intent

✅ Vertical Slice Architecture

• Features are grouped by use-case, not by technical concern

• Each slice contains its own:

  • Command / Query
  • Handler
  • Validator
  • Request / Response (Contracts)

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🧠 Core Design Concepts

🔹 Result Pattern

• Custom Result<T> implementation
• Unified success & failure handling
• Clear error propagation without throwing exceptions in business logic

🔹 Business Logic First

• All rules are enforced inside the Application layer
• No business logic leaks into Controllers or Infrastructure

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🔐 Security & Authorization

✅ Custom Authorization Policies

• Custom authorization policy to allow only assigned labors to change a Work Order status
• Prevents unauthorized status transitions
• Enforces real business constraints

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🧩 CQRS Pipeline Behaviors

Implemented using MediatR Pipeline Behaviors:

• 🔍 Validation Behavior

  • Uses FluentValidation
  • Automatically validates commands and queries

• 📊 Performance Monitoring Behavior

  • Logs execution time for each request
  • Helps detect slow operations

• 📝 Logging Behavior

  • Logs request details for observability and debugging

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Global Exception Handling

✅ Custom Exception Handling Middleware

• Centralized exception handling
• Consistent error responses
• Clean separation between exception handling and business logic

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🗄️ Data Access Layer

✅ Entity Framework Core

• Code First approach
• Clear entity configuration
• Migrations used for database evolution

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⚙️ Background Services & Real-Time Features

🔄 Background Services

• Background services are used to periodically check customer appointments
• If a customer is delayed beyond the allowed time, the related Work Order is automatically canceled
• Ensures workshop schedule consistency and reduces manual intervention

🔔 Real-Time Notifications

• Real-time communication is implemented to notify the team immediately when a Work Order status changes
• Enables instant UI updates without manual refresh
• Improves operational awareness and response time

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📦 Project Structure

src/
│
├── MechanicShop.API
│   ├── Controllers
│   ├── Middlewares          
│              
│
├── MechanicShop.Application
│   ├── Common               # Result Pattern, helpers, base abstractions
│   ├── Features             # CQRS Vertical Slices (Commands / Queries / Handlers)
│   └── DependencyInjection.cs
│
├── MechanicShop.Contracts
│   ├── Common              
│   ├── Requests             
│   ├── Responses            
│   └── Class1.cs           
│
├── MechanicShop.Domain
│   ├── Common               
│   ├── Customers           
│   ├── Employees            
│   ├── Identity            
│   ├── RepairTasks          
│   └── WorkOrders           
│
├── MechanicShop.Infrastructure
│   ├── BackgroundJobs       
│   ├── Data            
│   ├── Identity             
│   ├── Migrations           
│   ├── RealTime            
│   ├── Services             
│   ├── Settings             
│   └── DependencyInjection.cs
│
└── tests                    # Unit & integration tests

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🎯 Key Highlights

• ✔ Clean Architecture
• ✔ CQRS with MediatR
• ✔ Result Pattern
• ✔ Vertical Slice Architecture
• ✔ Custom Authorization Policies
• ✔ Pipeline Behaviors (Validation, Logging, Performance)
• ✔ Custom Exception Middleware
• ✔ EF Core Code First

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🧪 Project Status

✅ Development Completed

🧪 Currently Under Testing

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🚀 Final Notes

This project is built as a learning-focused yet production-oriented system, emphasizing:

• Correct architecture decisions
• Strong business logic enforcement
• Clean, readable, and maintainable code

It serves as a solid foundation for extending into a full-scale workshop management platform.