pagination

Pagination - Pagination Helper

A lightweight pagination package for Go that helps you handle pagination logic in your applications.

Installation

go get github.com/davidsugianto/go-pkgs/pagination

Quick Start

package main

import (
    "github.com/davidsugianto/go-pkgs/pagination"
)

func main() {
    // Create pagination with defaults (Page=1, PageSize=20)
    p := pagination.Pagination{}
    p = p.SetDefault()
    
    // Use for database queries
    offset := p.Offset()  // 0
    limit := p.Limit()    // 20
    
    // After querying total records
    p = p.SetTotal(145)
    // p.TotalPage will be calculated automatically: 8
}

Features

• ✅ Default Values - Automatically sets Page=1 and PageSize=20 when zero
• ✅ Offset/Limit Calculation - Easy calculation for database queries
• ✅ Total Pages - Automatically calculates total pages from total data
• ✅ JSON Support - JSON tags included for API responses

Usage

Basic Usage

// Custom pagination
p := pagination.Pagination{
    Page:     2,
    PageSize: 10,
}

offset := p.Offset()  // 10
limit := p.Limit()    // 10

With Defaults

// Zero values will be set to defaults
p := pagination.Pagination{
    Page:     0, // Will become 1
    PageSize: 0, // Will become 20
}
p = p.SetDefault()
// p.Page = 1, p.PageSize = 20

Database Query Example

// For SQL queries: SELECT * FROM users LIMIT ? OFFSET ?
p := pagination.Pagination{
    Page:     3,
    PageSize: 25,
}

offset := p.Offset()  // 50
limit := p.Limit()    // 25

// Query database
users := db.Query("SELECT * FROM users LIMIT ? OFFSET ?", limit, offset)

// After getting total count
totalUsers := db.Count("SELECT COUNT(*) FROM users")
p = p.SetTotal(totalUsers)
// p.TotalPage will be calculated automatically

API Response Example

p := pagination.Pagination{
    Page:     1,
    PageSize: 20,
}
p = p.SetTotal(145)

// The Pagination struct has JSON tags and can be used directly in responses
response := map[string]interface{}{
    "pagination": p,
    "data":       yourData,
}
// Returns: {"pagination":{"page":1,"page_size":20,"total_data":145,"total_page":8},...}

API Reference

Methods

SetDefault() Pagination

Sets default values when Page or PageSize is zero:

• Page: 0 → 1
• PageSize: 0 → 20

Limit() int

Returns the page size (limit for queries).

Offset() int

Calculates and returns the offset: (Page - 1) * PageSize

SetTotal(totalData int) Pagination

Sets the total number of records and calculates total pages:

• TotalData: Set to totalData
• TotalPage: Calculated as (totalData + PageSize - 1) / PageSize

Struct Fields

type Pagination struct {
    Page      int `form:"page" json:"page"`           // Current page (1-indexed)
    PageSize  int `form:"page_size" json:"page_size"` // Items per page
    TotalData int `json:"total_data"`                 // Total number of records
    TotalPage int `json:"total_page"`                 // Total number of pages
}

Examples

See the example/ directory for a complete working example.

cd example
go run main.go