valid

Valid 🛡️

A lightweight, fluent validation library for Go with zero dependencies. Features type-safe validators and built-in internationalization support.

Features ✨

• 🔄 Fluent chainable API
• 🎯 Type-specific validations
• 🌍 Built-in i18n support (EN/ES)
• ⚡ Zero external dependencies
• 🔍 Comprehensive error messages
• 💪 Strong type safety
• 🧪 100% test coverage

Installation 📦

go get -u github.com/techforge-lat/valid

Quick Start 🚀

package main

import (
    "fmt"
    "github.com/techforge-lat/valid"
)

type User struct {
    Age       int
    Email     string
    Score     float64
    Tags      []string
}

func (u *User) Validate() error {
    // Initialize validator with language preference
    v := valid.New(valid.ES) // or valid.EN for English

    v.Int("age", u.Age).
        Required().
        Between(18, 130)

    v.String("email", u.Email).
        Required().
        Email()

    v.Float("score", u.Score).
        Required().
        Between(0, 100).
        Precision(2)

    v.Slice("tags", u.Tags).
        Required().
        MinLength(1).
        MaxLength(5)

    if v.HasErrors() {
        return v.Errors()
    }

    return nil
}

func main() {
    user := &User{
        Age:     15,
        Email:   "invalid@email",
        Score:   75.456,
        Tags:    []string{},
    }

    if err := user.Validate(); err != nil {
        fmt.Printf("Errores de validación:\n%s\n", err)
    }
}

Internationalization 🌍

The library supports English and Spanish out of the box, with flexible language configuration:

Global Default Language

// Set default language globally (e.g., in init() or main())
valid.SetDefaultLanguage(valid.ES)

// Create validator with default language
v := valid.New()

// Check current default language
lang := valid.GetDefaultLanguage()

Instance-specific Language

// Override default language for specific validator
v1 := valid.New(valid.WithLanguage(valid.EN))
v2 := valid.New(valid.WithLanguage(valid.ES))
vDefault := valid.New() // Uses global default language

Custom Translations

// Add custom translations
valid.AddTranslation("custom_rule", valid.EN, "validation failed: %s")
valid.AddTranslation("custom_rule", valid.ES, "validación fallida: %s")

// Add multiple translations
valid.AddTranslations(map[string]map[valid.Language]string{
    "custom_rule": {
        valid.EN: "validation failed: %s",
        valid.ES: "validación fallida: %s",
    },
})

Available Validators 📝

String Validation

v.String("field", value).
    Required().
    MinLength(5).
    MaxLength(100).
    Email().
    URL().
    Pattern(regexp).
    Password()

Integer Validation

v.Int("field", value).
    Required().
    Min(0).
    Max(100).
    Between(18, 65).
    Positive().
    MultipleOf(5)

Float Validation

v.Float("field", value).
    Required().
    Positive().
    Between(0, 100).
    Precision(2)

Slice Validation

v.Slice("field", value).
    Required().
    MinLength(1).
    MaxLength(10).
    Each(func(v *valid.Validator, i int, item T) {
        // Validate each item
    })

Error Handling 🚨

Errors are returned in the selected language:

// English
type ValidationErrors []ValidationError
err.Error() // Returns: "age: must be between 18 and 130; email: invalid email format"

// Spanish
err.Error() // Returns: "age: debe estar entre 18 y 130; email: formato de email inválido"

Best Practices 💡

1. Create a validator instance with your preferred language:

v := valid.New(valid.ES) // or valid.EN

1. Chain validations fluently:

v.String("password", password).
    Required().
    MinLength(8).
    Password()

1. Add custom translations if needed:

valid.AddTranslation("my_rule", valid.EN, "custom validation message: %s")
valid.AddTranslation("my_rule", valid.ES, "mensaje de validación personalizado: %s")

Contributing 🤝

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

1. Fork the Project
2. Create your Feature Branch (git checkout -b feature/AmazingFeature)
3. Commit your Changes (git commit -m 'Add some AmazingFeature')
4. Push to the Branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

License 📄

This project is licensed under the MIT License - see the LICENSE file for details.

Support 💬

• Create an issue for bug reports
• Start a discussion for feature requests
• Check out the documentation

Acknowledgments 🙏

Special thanks to all contributors and users who have helped shape this library.

Made with ❤️ by [Your Name]