Implement Simplified Events Management System

Ticket ID: EVENTS-SIMPLE-001
Priority: High

**Feature Description**

Implement a simplified events system for community gatherings. Users can create events and register/unregister with a single click. No calendar integration, no statistics, no complex registration tracking.

**Acceptance Criteria**

1. Database Schema
```
sql

CREATE TABLE events (
id UUID PRIMARY KEY DEFAULT uuid_generate_v7(),
title VARCHAR(200) NOT NULL,
description TEXT NOT NULL,
body TEXT, -- Detailed event description
techs UUID[] DEFAULT ARRAY[]::UUID[], -- Related technologies
partners UUID[] DEFAULT ARRAY[]::UUID[], -- Partner organizations
created_by UUID REFERENCES users(id) ON DELETE SET NULL,
cover_image VARCHAR(500),
start_at TIMESTAMP NOT NULL,
ends_at TIMESTAMP NOT NULL,
registration_link VARCHAR(500), -- External registration (optional)
external_link VARCHAR(500), -- Additional event link
location VARCHAR(200) NOT NULL,
venue_details TEXT, -- Specific venue info
topic VARCHAR(100),
type VARCHAR(50) DEFAULT 'WORKSHOP' CHECK (type IN ('WORKSHOP', 'MEETUP', 'HACKATHON', 'CONFERENCE', 'NETWORKING', 'WEBINAR', 'TRAINING')),
participants UUID[] DEFAULT ARRAY[]::UUID[], -- Simple array of user IDs
created_at TIMESTAMP DEFAULT NOW(),
updated_at TIMESTAMP DEFAULT NOW()
);

-- Indexes for performance
CREATE INDEX idx_events_start_at ON events(start_at);
CREATE INDEX idx_events_type ON events(type);
CREATE INDEX idx_events_created_by ON events(created_by);
CREATE INDEX idx_events_participants ON events USING gin(participants);
```

2. Core Endpoints
- Public Endpoints (No Auth Required):
```
text

GET /api/v1/events # List events with filters & pagination
GET /api/v1/events/:id # Get event details
```

- Authenticated User Endpoints:
```
text

POST /api/v1/events # Create event
PUT /api/v1/events/:id # Update event (creator only)
DELETE /api/v1/events/:id # Delete event (creator or admin)
POST /api/v1/events/:id/register # Register for event (adds user to participants)
DELETE /api/v1/events/:id/register # Unregister from event (removes user from participants)
GET /api/v1/events/my-events # Get user's created events
GET /api/v1/events/my-registrations # Get events user is registered for
```

- Admin Endpoints:
```
text

DELETE /api/v1/admin/events/:id # Force delete any event
```

3. Filtering & Search

Query Parameters for `/api/v1/events`:

- type: WORKSHOP, MEETUP, HACKATHON, etc.

- topic: React, JavaScript, Open Source, etc.

- techs: Technology IDs (comma-separated)

- date: upcoming, past, all

- location: City, country

- search: Keyword search in title/description

- page, pageSize: Pagination

4. Caching Strategy

- Redis Cache Implementation:
```
javascript

const CACHE_KEYS = {
EVENTS_LIST: 'events:list:v1:', // + filters hash
EVENT_DETAIL: 'event:detail:', // + eventId
USER_EVENTS: 'events:user:', // + userId
};

const CACHE_TTL = {
EVENTS_LIST: 300, // 5 minutes
EVENT_DETAIL: 600, // 10 minutes
USER_EVENTS: 300 // 5 minutes
};

// Cache invalidation triggers:
// - New event created/updated/deleted
// - User registers/unregisters for event
```

5. Response Formats

Event Listing Response:
```
json

{
"success": true,
"data": [
{
"id": "uuid",
"title": "Introduction to React Hooks Workshop",
"description": "A hands-on session covering useState, useEffect, and custom hooks...",
"coverImage": "url",
"startAt": "2025-01-10T13:00:00Z",
"endsAt": "2025-01-10T16:00:00Z",
"location": "DevByte HQ, Lagos",
"type": "WORKSHOP",
"topic": "React",
"techs": [
{ "id": "react-uuid", "name": "React", "icon": "url" },
{ "id": "js-uuid", "name": "JavaScript", "icon": "url" }
],
"participants": ["user1-uuid", "user2-uuid", "user3-uuid"],
"participantCount": 3,
"registrationLink": "https://external-registration.com",
"formattedDate": "01-10-2025 (01:00pm - 04:00pm)",
"createdBy": {
"id": "user-uuid",
"fullName": "Event Organizer",
"profilePicture": "url"
},
"hasRegistered": false, // For authenticated users
"isCreator": false // For authenticated users
}
]
}
```

6. Registration Logic ✅

- Simple array operations:
```
javascript

// Register user
const event = await Event.findByPk(eventId);
if (!event.participants.includes(userId)) {
event.participants = [...event.participants, userId];
await event.save();
}

// Unregister user
event.participants = event.participants.filter(id => id !== userId);
await event.save();
```

- Rules:

- No duplicate registrations

- Users can register/unregister anytime

- No registration limits

- No waitlists

- No approval process

7. Validation Rules ✅

- [ ] Title: Required, 5-200 characters(no special characters to prevent sql injection attacks)

- [ ] Description: Required, 50-500 characters(no special characters to prevent sql injection attacks)

- [ ] Start/End Time: Required

- [ ] Location: Required, 2-200 characters(no special characters to prevent sql injection attacks)

- [ ] Type: Required, from enum values

- [ ] Registration Link: Optional, valid URL

- [ ] Cover Image: Optional, valid URL

- [ ] Techs/Partners: Optional, arrays of valid IDs

9. Testing ✅

- [ ] Unit tests for event creation/validation

- [ ] Integration tests for registration/unregistration

- [ ] Authorization tests (creator vs non-creator)

10. Documentation ✅

- [ ] Complete Swagger/OpenAPI documentation

- [ ] Simple registration flow documentation

- [ ] Cache behavior documentation

No repository files, tests, or entry points are named. Start by locating the existing API, database, authentication, Redis, and test structure, then compare it with the proposed events schema and endpoints; done means the listed event, registration, validation, authorization, caching, testing, and documentation requirements are implemented.

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