# Social Commerce Platform (Intro)

Nexgate is a unified social commerce platform that combines eCommerce, event management, and social networking into a single ecosystem. Built for the East African market, Nexgate enables users to buy, sell, connect, and experience — all in one place.

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## The Concept

Nexgate reimagines how commerce happens online. Instead of separating shopping, events, and social media into different apps, Nexgate brings them together.

**User creates** → Product or Event → **Posts to Social** → Followers see in feed → **Purchase or Book**

A product isn't just listed in a shop — it's shared, liked, and commented on. An event isn't just a ticket page — it's a post that spreads organically through your network.

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## Platform Architecture

Nexgate follows a microservices architecture with nine independent services communicating via RabbitMQ message broker and backed by PostgreSQL databases.

### Core Services

1. **Authentication** — User registration, login, JWT tokens, OAuth, device management
2. **User Profile** — Profiles, followers/following, privacy settings, trust scores
3. **File Manager** — Media uploads, image processing, BlurHash, video transcoding via FFmpeg
4. **Payment** — Payment methods, M-Pesa/Selcom/Tembo Plus integration, escrow, transactions
5. **Direct Message** — Real-time private messaging, conversations, media sharing

### Business Services

6. **E-Commerce** — Shops, products, orders, cart, checkout, reviews, seller verification
7. **E-Events** — Event creation, ticketing, RSA-signed tickets, check-ins, organizer ratings
8. **E-Social** — Posts, feeds, likes, comments, reposts, polls, mentions, hashtags

### External Service

9. **Notification** — Push notifications, in-app alerts, email, SMS (async via RabbitMQ)

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## Architecture Diagram

[![nexgate_arc_diagram.png](https://doc-hub.qbitspark.com/uploads/images/gallery/2025-12/scaled-1680-/nexgate-arc-diagram.png)](https://doc-hub.qbitspark.com/uploads/images/gallery/2025-12/nexgate-arc-diagram.png)

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## Service Relationships

| Service | Role | Connects To |
|---------|------|-------------|
| **Authentication** | Identity, tokens, sessions | Redis, PostgreSQL Core, RabbitMQ |
| **User Profile** | Profiles, follows, trust scores | PostgreSQL Core, RabbitMQ |
| **File Manager** | Media uploads, processing | FFmpeg, MinIO, PostgreSQL Core |
| **Payment** | Transactions, escrow | M-Pesa, Selcom, Tembo Plus, PostgreSQL Core, RabbitMQ |
| **Direct Message** | Private conversations | PostgreSQL Core, RabbitMQ |
| **E-Commerce** | Shops, products, orders | E-Social (embed products in posts), PostgreSQL Core, RabbitMQ |
| **E-Events** | Events, tickets, check-ins | E-Social (embed events in posts), PostgreSQL Core, RabbitMQ |
| **E-Social** | Posts, feeds, interactions | E-Commerce, E-Events (receives embeds), PostgreSQL Core, RabbitMQ |
| **Notification** | Push, email, SMS | RabbitMQ (consumes events), PostgreSQL Notif |

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## Data Flow Summary

| Flow | Path |
|------|------|
| **User creates product** | E-Commerce → Post to E-Social → Followers see in feed |
| **User creates event** | E-Events → Post to E-Social → Followers see in feed |
| **User uploads media** | File Manager → FFmpeg (if video) → MinIO → BlurHash generated |
| **User makes payment** | Payment → External Provider (M-Pesa/Selcom/Tembo) → Callback → Update order |
| **Any action triggers notification** | Service → RabbitMQ → Notification Service → Push/Email/SMS |

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## Infrastructure Components

| Component | Purpose |
|-----------|---------|
| **PostgreSQL (Core)** | Shared DB for Auth, User, File, Payment, DM, E-Commerce, E-Events, E-Social |
| **PostgreSQL (Notif)** | Separate DB for Notification service |
| **Redis** | Session storage, caching, rate limiting |
| **RabbitMQ** | Async messaging, triggers notifications |
| **MinIO** | S3-compatible object storage for all media |
| **FFmpeg** | Video transcoding, thumbnails, compression |

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## Tech Stack

| Layer | Technology |
|-------|------------|
| **Backend** | Java 21, Spring Boot 3.x |
| **Database** | PostgreSQL (Core + Notification) |
| **Cache** | Redis |
| **Messaging** | RabbitMQ |
| **Storage** | MinIO (S3-compatible) |
| **Media Processing** | FFmpeg |
| **Payments** | M-Pesa, Selcom, Tembo Plus |
| **Security** | JWT, RSA signatures, device fingerprinting |