SocialSync (Digital Marketing Automation Tool)

A full-stack digital marketing application designed to help users schedule, manage, and publish content across multiple social media platforms simultaneously, including LinkedIn and X/Twitter.

This project demonstrates modern .NET development, React, Clean Architecture, and complex third-party API integrations such as OAuth 2.0, media uploads, and background processing.

🛠 Tech Stack

• Backend: .NET 10, C# 12
• Frontend: React.js, Tailwind CSS, Vite
• Database: PostgreSQL
• ORM: Entity Framework Core
• Background Processing: Hangfire with PostgreSQL storage
• Cloud Storage: Cloudinary for media assets
• AI Integration: Azure OpenAI / Gemini for AI-assisted post generation

Features & Architecture

The application was engineered with scalability, security, and reliability in mind, following Clean Architecture principles.

1. Clean Architecture & Modular Services

The codebase is decoupled to support testability and maintainability:

• Domain: Core entities such as User, Post, and SocialAccount.
• Application: Business rules and interfaces such as IPostService, ISocialMediaProvider, and IEncryptionService.
• Infrastructure: EF Core DbContext, migrations, and external API implementations.
• API: Presentation layer, Hangfire configuration, rate limiting, and dependency injection setup.

2. Advanced Security & Encryption

• Zero plain-text tokens: OAuth access and refresh tokens are encrypted at rest and decrypted only at runtime using AES encryption.
• OAuth 2.0 and PKCE: Complete authorization flows were implemented, including PKCE challenge handling for the X API.
• Secure configuration: API keys and secrets are excluded from source control with .gitignore; local development can use .NET User Secrets.

3. Queue System & Scheduled Publishing

• Hangfire powers asynchronous background processing.
• Users can schedule posts for future dates.
• The background worker retrieves due posts, decrypts the required platform tokens, and publishes content asynchronously.

4. Resiliency & Retry Mechanisms

• Hangfire retries background jobs automatically for transient failures.
• Publication state is tracked per platform so a multi-platform post can recover platform-by-platform.

5. Rate Limiting

• Inbound protection: ASP.NET Core rate limiting protects expensive endpoints such as AI generation.
• Outbound throttling: Background jobs delay between HTTP requests to reduce 429 responses and avoid spam restrictions.

6. Native Media Uploads

• LinkedIn: Implements the UGC image upload flow for native media publishing.
• X/Twitter: Supports media upload flow for attaching images to posts.

🚀 Getting Started

Prerequisites

• .NET 10 SDK
• Node.js and npm
• PostgreSQL running locally or via Docker
• API keys for X Developer Portal, LinkedIn Developer Portal, and Cloudinary

Backend Setup

1. Navigate to the API directory:

   cd SocialMediaManager.API

2. Configure secrets. Do not place real keys in appsettings.json.

   dotnet user-secrets init
   dotnet user-secrets set "ConnectionStrings:DefaultConnection" "Host=localhost;Database=SocialDb;Username=postgres;Password=yourpassword"
   dotnet user-secrets set "OAuth:X:ClientId" "<YOUR_X_CLIENT_ID>"
   dotnet user-secrets set "OAuth:X:ClientSecret" "<YOUR_X_CLIENT_SECRET>"
   dotnet user-secrets set "OAuth:LinkedIn:ClientId" "<YOUR_LINKEDIN_CLIENT_ID>"
   dotnet user-secrets set "OAuth:LinkedIn:ClientSecret" "<YOUR_LINKEDIN_CLIENT_SECRET>"

3. Apply database migrations:

   dotnet ef database update --project ../SocialMediaManager.Infrastructure

4. Run the API:

   dotnet run

Frontend Setup

1. Navigate to the frontend directory:

   cd ../SocialMediaManager.UI

2. Install dependencies:

   npm install

3. Start the Vite development server:

   npm run dev

Screenshots

Connect Channels

Connect and manage your LinkedIn and X/Twitter accounts securely. The application displays your account usernames and allows easy disconnection when needed.

Create Post

Compose posts with optional AI-generated captions using OpenAI or Gemini. Add images, select target platforms, and schedule publication directly from the interface.

Scheduled Posts

View all scheduled posts with per-platform publication status. Track which posts have been published or are pending, with real-time status updates from the background job processor.

💡 Technical Challenges Overcome

• Strict API scopes: Requested the correct X scopes, including tweet.read, tweet.write, and users.read, to avoid authorization errors.
• Complex JSON schemas: Used dynamic dictionary-based payloads to match LinkedIn UGC API requirements.
• React StrictMode OAuth handling: Added a useRef guard to prevent duplicate OAuth code exchanges during development.