Project: Real-time Task Management System

Overview: This is a task management system where users can create, read, update, and delete tasks. The system will use WebSockets for real-time updates and a database for persistent storage.

Key components:

1. HTTP server for API endpoints
2. WebSocket server for real-time updates
3. Database integration (e.g., PostgreSQL)
4. CRUD operations for tasks
5. Channels for handling concurrent operations

Features:

1. User authentication
2. Create, read, update, and delete tasks
3. Real-time task updates for all connected clients
4. Task filtering and sorting
5. Task assignment to users

Implementation steps:

1. Set up the project structure and database
2. Implement HTTP server with basic CRUD operations
3. Add WebSocket support for real-time updates
4. Use channels for handling concurrent operations
5. Implement user authentication
6. Add advanced features like filtering and sorting

This project will help you learn:

• Go's HTTP package for creating a web server
• Database operations using a SQL driver (e.g., lib/pq for PostgreSQL)
• WebSocket implementation in Go
• Concurrency with goroutines and channels
• JSON marshaling and unmarshaling
• Error handling in Go
• Project structure and organization

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1. Project Setup

   • Initialize a new Go module
   • Set up a project structure with separate packages for handlers, models, and database operations
   • Choose and set up a SQL database (e.g., PostgreSQL)

2. Database Schema

   • Users table: id, username, password_hash, email, created_at
   • Tasks table: id, title, description, status, created_at, updated_at, user_id (foreign key to users)

3. User Authentication

   • Implement user registration with username, email, and password
   • Implement user login with JWT token generation
   • Create middleware for authenticating protected routes

4. HTTP Server

   • Set up an HTTP server using the standard "net/http" package
   • Implement the following RESTful API endpoints:
     • POST /register - User registration
     • POST /login - User login
     • GET /tasks - Retrieve all tasks for the authenticated user
     • GET /tasks/:id - Retrieve a specific task
     • POST /tasks - Create a new task
     • PUT /tasks/:id - Update an existing task
     • DELETE /tasks/:id - Delete a task

5. WebSocket Server

   • Implement a WebSocket server for real-time updates
   • Create a handler for WebSocket connections
   • Implement a mechanism to broadcast task updates to all connected clients

6. CRUD Operations

   • Implement Create, Read, Update, and Delete operations for tasks
   • Use prepared statements for database queries to prevent SQL injection
   • Implement proper error handling for database operations

7. Concurrency with Channels

   • Use channels to handle communication between HTTP handlers and WebSocket broadcasts
   • Implement a goroutine to listen for task updates and broadcast them to WebSocket clients

8. Task Filtering and Sorting

   • Implement query parameters for the GET /tasks endpoint to allow filtering by status and sorting by creation date

9. Error Handling

   • Implement custom error types for different scenarios (e.g., NotFoundError, ValidationError)
   • Return appropriate HTTP status codes and error messages in API responses

10. Logging

    • Implement logging for server events, errors, and access logs

11. Configuration

    • Use environment variables or a configuration file for database credentials, server port, and JWT secret

12. Testing

    • Write unit tests for critical functions
    • Implement integration tests for API endpoints

13. Documentation

    • Create API documentation using a tool like Swagger
    • Write a README.md file with project setup and running instructions

14. (Optional) Docker

    • Create a Dockerfile for the application
    • Set up docker-compose for easy deployment with the database

Detailed Implementation Steps:

1. Project Setup

   mkdir task-management-system
   cd task-management-system
   go mod init github.com/yourusername/task-management-system
   

2. Create main.go file with basic server setup

   package main
   
   import (
       "log"
       "net/http"
   )
   
   func main() {
       // TODO: Initialize database connection
       // TODO: Set up routes
       log.Println("Server starting on :8080")
       log.Fatal(http.ListenAndServe(":8080", nil))
   }

3. Set up database connection in a separate package

4. Implement user authentication

5. Create handlers for CRUD operations

6. Implement WebSocket functionality

7. Add channels for real-time updates

8. Implement filtering and sorting

9. Add error handling and logging

10. Write tests

11. Document the API

This structure provides a solid foundation for building the Real-time Task Management System. As you implement each part, you'll gain experience with Go's core concepts, including HTTP servers, database operations, WebSockets, channels, and concurrency.