Good Night API - Sleep Tracking Application

A Ruby on Rails API application for tracking sleep patterns with social features. Users can record their sleep sessions and follow friends to view their sleep data.

Features

• 🛌 Sleep Tracking: Clock in/out functionality for tracking sleep sessions
• 👥 Social Features: Follow/unfollow users and view friends' sleep records
• 📊 Analytics: View sleep records sorted by duration
• ⚡ High Performance: Optimized with strategic caching and background processing

Quick Start

Prerequisites

• Ruby 3.2+
• Rails 8.0
• PostgreSQL 14+

Installation

# Clone the repository
git clone https://github.com/zneuray/good-night-demo.git
cd good-night-demo

# Install dependencies
bundle install

# Setup database
rails db:create db:migrate db:seed

# Start SolidQueue (for background job)
rails solid_queue:start

# Start the application
rails server

The API will be available at http://localhost:3000

API Documentation

Sleep Records

Clock In

Start a new sleep session.

Clock Out

End the most recent sleep session.

Get Sleep Records

Retrieve all completed sleep records for the authenticated user.

Get Following Sleep Records

Retrieve friends' sleep records from the previous week, sorted by duration.

User Following

Follow User

Follow another user to see their sleep records.

Unfollow User

Stop following a user.

Architecture

Performance Optimizations

The application implements several performance strategies optimized for large datasets:

Solid Cache for Large Data Caching

The application uses Solid Cache - a database-backed cache store perfect for handling large datasets and high-traffic applications:

• High Performance: SQLite-based caching with excellent read/write performance
• Large Data Support: Handles multi-gigabyte cache datasets efficiently
• Persistence: Cache survives application restarts unlike memory-based stores
• Scalability: Designed for production applications with high cache volumes

Strategic Caching with Optimized TTLs

• Last Incomplete Sleep Record: 24 hours TTL
• Following Sleep Records: 1 hour TTL
• Weekly Sleep Data: 1 month TTL
• User Following Lists: 6 hours TTL

Database Optimization for Large Datasets

• Composite Indexes: Optimized for frequently queried columns
• Partial Indexes: For incomplete sleep records
• Database-Level Sorting: Using stored duration column for performance
• Optimized queries: Use includes to avoid N+1 problems

Background Processing with Solid Queue

• Asynchronous Cache Warming: Pre-compute expensive queries
• Weekly Analytics Processing: Background computation of sleep statistics
• Batch Cache Updates: Efficient handling of large follower lists

Service Architecture

The application follows Rails best practices with service objects for complex business logic:

app/
├── controllers/api/users/
│   └── sleep_records_controller.rb    # Thin controllers
├── models/
│   ├── user.rb                        # User relationships and social features
│   ├── sleep_record.rb                # Sleep data with duration tracking
│   └── follow.rb                      # Following relationships
├── services/sleep/
│   ├── clock_in_service.rb            # Sleep session creation
│   ├── clock_out_service.rb           # Sleep session completion
│   ├── following_service.rb           # Social sleep data retrieval
│   └── cache_handle_service.rb        # Centralized caching logic
└── serializers/
    └── sleep_records_serializer.rb    # Consistent API responses

Business Logic

Sleep Tracking Rules

1. Clock In: Always creates a new sleep record with duration: 0
2. Clock Out: Updates the most recent incomplete sleep record
3. Multiple Clock-ins: Allowed - creates multiple incomplete records
4. Clock Out Logic: Only completes the latest incomplete record
5. Duration Calculation: Automatically calculated on clock out

Social Features

1. Following: Users can follow/unfollow each other
2. Sleep Visibility: Only completed sleep records are visible to followers
3. Time Period: Following endpoint shows previous week's data only
4. Sorting: Results sorted by sleep duration (descending)