golib/database

Database Package

Comprehensive database management with GORM ORM integration and generic Key-Value store abstraction.

AI Disclaimer (EU AI Act Article 50.4): AI assistance was used solely for testing, documentation, and bug resolution under human supervision.

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Table of Contents

• Overview
• Key Features
• Architecture
• GORM Package
• Key-Value Packages
• Installation
• Quick Start
• Performance
• Use Cases
• Best Practices
• Testing
• Contributing
• Future Enhancements
• Related Documentation
• License

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Overview

The database package collection provides two complementary database paradigms:

1. GORM Package - Relational database support with ORM
2. KV Packages - Generic Key-Value store abstraction

Design Philosophy

• Abstraction: Clean interfaces hiding implementation complexity
• Type Safety: Leverage Go generics for compile-time safety
• Performance: Efficient connection pooling and caching
• Observability: Built-in monitoring and health checks
• Flexibility: Support multiple databases and storage backends

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Key Features

GORM Package

Feature	Description
Multi-DB Support	MySQL, PostgreSQL, SQLite, SQL Server
Connection Pooling	Configurable pool settings (idle, max, lifetime)
Logger Integration	golib/logger integration with log levels
Context Support	Full context.Context for cancellation/deadlines
Monitoring	Health checks and connection status
Config Validation	Struct validation with go-playground/validator
Thread-Safe	Safe for concurrent use

Key-Value Packages

Package	Purpose
kvtypes	Type definitions and interfaces
kvdriver	Database driver abstraction
kvitem	Individual key-value item operations
kvmap	Map-based operations
kvtable	Table-level operations

---

Architecture

Package Structure

database/
├── gorm/                    # GORM ORM integration
│   ├── config.go           # Configuration structures
│   ├── driver.go           # Database driver detection
│   ├── interface.go        # Public interfaces
│   ├── model.go            # Implementation
│   ├── monitor.go          # Health monitoring
│   └── errors.go           # Error definitions
│
└── kv*/                     # Key-Value packages
    ├── kvtypes/            # Type definitions
    ├── kvdriver/           # Driver abstraction
    ├── kvitem/             # Item operations
    ├── kvmap/              # Map operations
    └── kvtable/            # Table operations

GORM Architecture

┌─────────────────────────────────────────────────────┐
│              GORM Package                            │
│                                                      │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────┐ │
│  │   Config     │  │   Monitor    │  │  Logger  │ │
│  │  Validation  │  │  Health Check│  │ Integr.  │ │
│  └──────────────┘  └──────────────┘  └──────────┘ │
│         │                  │                │       │
│         ▼                  ▼                ▼       │
│  ┌──────────────────────────────────────────────┐  │
│  │         GORM Interface                       │  │
│  │  (Connection Pool, Transaction, Migration)   │  │
│  └──────────────────────────────────────────────┘  │
│                        │                             │
│                        ▼                             │
│  ┌──────────────────────────────────────────────┐  │
│  │      Database Drivers                        │  │
│  │  MySQL │ PostgreSQL │ SQLite │ SQL Server   │  │
│  └──────────────────────────────────────────────┘  │
└─────────────────────────────────────────────────────┘

Key-Value Packages Architecture

┌──────────────────────────────────────────────────────────────────┐
│                    KV Packages Ecosystem                          │
│                                                                   │
│  ┌─────────────────────────────────────────────────────────┐    │
│  │                     kvtypes                              │    │
│  │  (Generic Types [K comparable, V any])                  │    │
│  │  - Interfaces                                            │    │
│  │  - Type Definitions                                      │    │
│  │  - Common Structures                                     │    │
│  └─────────────────────────────────────────────────────────┘    │
│                              │                                    │
│                              ▼                                    │
│  ┌─────────────────────────────────────────────────────────┐    │
│  │                    kvdriver                              │    │
│  │  (Database Driver Abstraction)                          │    │
│  │  - Connection Management                                │    │
│  │  - Generic Operations [K, V]                            │    │
│  │  - Driver Interface                                     │    │
│  └─────────────────────────────────────────────────────────┘    │
│                              │                                    │
│          ┌───────────────────┼───────────────────┐              │
│          ▼                   ▼                   ▼              │
│  ┌──────────────┐   ┌──────────────┐   ┌──────────────┐       │
│  │   kvitem     │   │    kvmap     │   │   kvtable    │       │
│  │              │   │              │   │              │       │
│  │ Single Item  │   │  Map-based   │   │   Table      │       │
│  │ Operations:  │   │ Operations:  │   │ Operations:  │       │
│  │              │   │              │   │              │       │
│  │ - Get        │   │ - GetAll     │   │ - Schema     │       │
│  │ - Set        │   │ - SetAll     │   │ - Namespace  │       │
│  │ - Delete     │   │ - Delete     │   │ - Create     │       │
│  │ - Exists     │   │ - Keys       │   │ - Drop       │       │
│  │ - Expire     │   │ - Values     │   │ - List       │       │
│  │              │   │ - Range      │   │ - Migrate    │       │
│  └──────────────┘   └──────────────┘   └──────────────┘       │
│          │                   │                   │              │
│          └───────────────────┼───────────────────┘              │
│                              ▼                                    │
│  ┌─────────────────────────────────────────────────────────┐    │
│  │              Storage Backend                             │    │
│  │  (Redis, BadgerDB, BoltDB, etc.)                        │    │
│  └─────────────────────────────────────────────────────────┘    │
└──────────────────────────────────────────────────────────────────┘

Data Flow:
  Application → kvitem/kvmap/kvtable → kvdriver → Storage Backend
  
Type Safety:
  Compile-time type checking through Go generics [K comparable, V any]
  
Abstraction Layers:
  1. kvtypes:  Generic type system
  2. kvdriver: Storage abstraction
  3. kvitem/kvmap/kvtable: Operation-specific interfaces

---

GORM Package

Supported Databases

Database	Driver	CGO Required	Status
MySQL	gorm.io/driver/mysql	No	✅ Supported
PostgreSQL	gorm.io/driver/postgres	No	✅ Supported
SQLite	gorm.io/driver/sqlite	Yes	✅ Supported
SQL Server	gorm.io/driver/sqlserver	No	✅ Supported

Installation

go get github.com/nabbar/golib/database/gorm

# Install database driver
go get -u gorm.io/driver/mysql        # MySQL
go get -u gorm.io/driver/postgres     # PostgreSQL
go get -u gorm.io/driver/sqlite       # SQLite (requires CGO)
go get -u gorm.io/driver/sqlserver    # SQL Server

Configuration

type Config struct {
    Driver               Driver          // Database driver (MySQL, PostgreSQL, etc.)
    Name                 string          // Connection name/identifier
    DSN                  string          // Data Source Name
    
    // Connection Pool
    EnableConnectionPool bool            // Enable connection pooling
    PoolMaxIdleConns    int              // Max idle connections
    PoolMaxOpenConns    int              // Max open connections  
    PoolMaxConnLifetime time.Duration    // Max connection lifetime
    PoolMaxConnIdleTime time.Duration    // Max connection idle time
    
    // GORM Options
    SkipDefaultTransaction bool          // Skip default transaction
    PrepareStmt           bool           // Prepare statements
    DisableAutomaticPing  bool           // Disable automatic ping
    
    // Logger
    LogLevel              logger.LogLevel // GORM log level
    LogThreshold          time.Duration   // Slow query threshold
}

Quick Start

import (
    "log"
    libgorm "github.com/nabbar/golib/database/gorm"
)

func main() {
    // Configure database
    cfg := &libgorm.Config{
        Driver: libgorm.DriverMysql,
        Name:   "mydb",
        DSN:    "user:pass@tcp(localhost:3306)/dbname?charset=utf8mb4",
        EnableConnectionPool: true,
        PoolMaxIdleConns:     10,
        PoolMaxOpenConns:     100,
    }
    
    // Create database instance
    db, err := libgorm.New(cfg)
    if err != nil {
        log.Fatal(err)
    }
    defer db.Close()
    
    // Get GORM DB
    gormDB := db.GetDB()
    
    // Use GORM as usual
    type User struct {
        ID   uint
        Name string
    }
    gormDB.AutoMigrate(&User{})
    gormDB.Create(&User{Name: "Alice"})
}

Monitoring

import (
    libgorm "github.com/nabbar/golib/database/gorm"
    montps "github.com/nabbar/golib/monitor/types"
)

// Register health check
func setupMonitoring(db libgorm.Database, pool montps.Pool) {
    monitor := db.Monitor(context.Background())
    
    pool.RegisterPool("database", func(ctx context.Context) (bool, error) {
        return monitor.IsRunning(), nil
    })
}

Context Management

// With context cancellation
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()

// Query with context
var users []User
result := db.GetDB().WithContext(ctx).Find(&users)
if result.Error != nil {
    log.Printf("Query error: %v", result.Error)
}

---

Key-Value Packages

The KV packages provide a generic, type-safe abstraction for key-value storage.

Package Overview

kvtypes - Core type definitions:

• Generic types with [K comparable, V any]
• Interface definitions
• Common structures

kvdriver - Driver abstraction:

• Database driver interface
• Connection management
• Generic operations

kvitem - Item operations:

• Single key-value operations
• Get, Set, Delete
• Expiration support

kvmap - Map operations:

• Bulk operations
• Map-based interface
• Batch processing

kvtable - Table operations:

• Table-level abstractions
• Namespace support
• Schema management

Example

import (
    "github.com/nabbar/golib/database/kvdriver"
    "github.com/nabbar/golib/database/kvitem"
)

// Create driver (implementation-specific)
driver := kvdriver.New(config)

// Use items
item := kvitem.New[string, User](driver, "users")
item.Set(ctx, "user:123", User{ID: 123, Name: "Alice"})

user, err := item.Get(ctx, "user:123")
if err != nil {
    log.Fatal(err)
}

---

Performance

GORM Package

Connection Pooling:

• Idle Connections: Reused for new queries (minimal overhead)
• Max Open Connections: Prevents database overload
• Connection Lifetime: Automatic recycling of stale connections

Benchmarks (MySQL):

Operation	Time	Notes
Simple Query	~500µs	With connection pool
Insert	~1ms	Single record
Batch Insert (100)	~50ms	Using CreateInBatches
Transaction	~2ms	Begin/Commit overhead
Connection Open	~5ms	First connection (one-time)

Benchmarks on localhost MySQL 8.0, AMD64

Key-Value Packages

Generic Overhead:

• Zero runtime overhead (generics compiled away)
• Type safety at compile time
• Inlining of generic functions

---

Use Cases

GORM Package

Web Applications

// User management API
func GetUser(c *gin.Context) {
    db := c.MustGet("db").(libgorm.Database)
    
    var user User
    result := db.GetDB().First(&user, c.Param("id"))
    if result.Error != nil {
        c.JSON(404, gin.H{"error": "user not found"})
        return
    }
    
    c.JSON(200, user)
}

Multi-Tenant Applications

// Separate databases per tenant
func getTenantDB(tenantID string) (libgorm.Database, error) {
    cfg := &libgorm.Config{
        Driver: libgorm.DriverPostgres,
        DSN:    fmt.Sprintf("host=localhost user=%s dbname=tenant_%s", user, tenantID),
    }
    return libgorm.New(cfg)
}

Migrations

// Database migrations
db.GetDB().AutoMigrate(&User{}, &Product{}, &Order{})

KV Packages

Session Storage

sessions := kvitem.New[string, Session](driver, "sessions")
sessions.Set(ctx, sessionID, sessionData)

Caching Layer

cache := kvitem.New[string, CachedData](driver, "cache")
cache.SetWithExpiration(ctx, key, data, 5*time.Minute)

---

Best Practices

GORM

1. Use Connection Pooling

cfg.EnableConnectionPool = true
cfg.PoolMaxIdleConns = 10
cfg.PoolMaxOpenConns = 100

2. Set Connection Lifetimes

cfg.PoolMaxConnLifetime = time.Hour
cfg.PoolMaxConnIdleTime = 10 * time.Minute

3. Use Contexts

ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
db.GetDB().WithContext(ctx).Find(&users)

4. Handle Errors

result := db.GetDB().Create(&user)
if result.Error != nil {
    log.Printf("Error: %v", result.Error)
}

5. Close Connections

defer db.Close()

KV Packages

1. Use Generics for Type Safety

// Type-safe
users := kvitem.New[string, User](driver, "users")

// Avoid any
items := kvitem.New[string, any](driver, "data") // Less safe

2. Handle Context Cancellation

ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
defer cancel()
item.Set(ctx, key, value)

---

Testing

Comprehensive testing documentation is available in TESTING.md.

Quick Test:

cd database/gorm
go test -v -cover

With SQLite (requires CGO):

CGO_ENABLED=1 go test -v -cover

Test Metrics:

• GORM: 41 test specifications, 61.6% coverage (with CGO)
• Ginkgo v2 + Gomega framework
• Multi-database testing

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Contributing

Contributions are welcome! Please follow these guidelines:

Code Contributions

• Do not use AI to generate package implementation code
• AI may assist with tests, documentation, and bug fixing
• All contributions must pass existing tests
• Maintain or improve test coverage
• Follow existing code style and patterns

Documentation

• Update README.md for new features
• Add examples for common use cases
• Keep TESTING.md synchronized
• Document all public APIs with GoDoc

Testing

• Write tests for all new features
• Test with multiple databases (MySQL, PostgreSQL, SQLite)
• Verify connection pool behavior
• Include error cases

Pull Requests

• Provide clear description of changes
• Reference related issues
• Include test results
• Update documentation

See CONTRIBUTING.md for detailed guidelines.

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Future Enhancements

Potential improvements for future versions:

GORM Package

• Connection pool metrics and monitoring dashboard
• Automatic failover and replica support
• Query performance profiling
• Schema versioning and migration tools
• Multi-database transaction support

KV Packages

• Redis driver implementation
• Bolt/BadgerDB driver implementation
• TTL and expiration policies
• Distributed locking
• Pub/Sub support

General

• Performance benchmarking suite
• Visual query analyzer
• Automatic index suggestions
• Database comparison tools

Suggestions and contributions are welcome via GitHub issues.

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Related Documentation

External Libraries

• GORM - The fantastic ORM library for Go
• GORM Drivers - Database driver documentation
• go-playground/validator - Struct validation
• Ginkgo Testing - BDD testing framework

Related Golib Packages

• logger - Logging integration
• monitor - Health monitoring
• config - Configuration management
• context - Context management

Database Documentation

• MySQL - MySQL official documentation
• PostgreSQL - PostgreSQL documentation
• SQLite - SQLite documentation
• SQL Server - SQL Server documentation

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License

MIT License - See LICENSE file for details.

Copyright (c) 2019 Nicolas JUHEL

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Resources

• Issues: GitHub Issues
• Documentation: GoDoc
• Testing Guide: TESTING.md
• GORM Documentation: gorm.io
• Contributing: CONTRIBUTING.md
• Source Code: GitHub Repository

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This package is part of the golib project.