github.com/walterlicinio/validgo

ValidGo

ValidGo is flexible data validation library for Go, providing a fluent interface for validating complex data structures.

Installation

To install ValidGo, use go get:

go get github.com/walterlicinio/validgo

Usage

Here's a quick example of how to use ValidGo:

package main

import (
    "fmt"
    "github.com/walterlicinio/validgo"
)

type User struct {
    Name  string
    Age   int
    Email string
}

func main() {
    user := User{Name: "John Doe", Age: 25, Email: "[e-mail]"}

    v := validgo.New(user)
    v.Field("Name").IsString().MinLength(2).MaxLength(50)
    v.Field("Age").IsInt().Min(18).Max(120)
    v.Field("Email").IsEmail()

    if v.HasErrors() {
        for _, err := range v.Errors() {
            fmt.Println(err)
        }
    } else {
        fmt.Println("Validation passed")
    }
}

Features

• Fluent interface for easy and readable validation rules
• Support for nested struct validation
• Built-in validators for common types (string, int, float)
• Custom validation rules
• Data transformation during validation
• Comprehensive error collection

Available Validators

• IsString(), MinLength(), MaxLength()
• IsInt(), Min(), Max()
• IsFloat(), MinFloat(), MaxFloat()
• IsEmail()
• IsPositive()
• Matches() (regex matching)
• IsAlpha(), IsAlphanumeric(), IsNumeric()
• Custom() (for custom validation rules)
• Transform() (for data transformation)

Advanced Usage Examples

Custom Validation

You can use the Custom() method to implement custom validation rules. Here's an example that checks if the user's name contains a space:

user := User{Name: "John Doe", Age: 25, Email: "[e-mail]"}

v := validgo.New(user)
v.Field("Name").Custom(func(value interface{}) bool {
    name, ok := value.(string)
    if !ok {
        return false
    }
    return strings.Contains(name, " ")
}).WithError("Name must contain a space")

if v.HasErrors() {
    for _, err := range v.Errors() {
        fmt.Println(err)
    }
} else {
    fmt.Println("Validation passed")
}

Contributing

Contributions to ValidGo are welcome! Please feel free to submit a Pull Request.