GoValidator 🚀

A powerful and lightweight struct validation library for Go, inspired by Java's Bean Validation.

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📌 Features

✅ Simple and powerful validation rules
✅ Supports string, number, boolean, date, and collection validation
✅ Custom error messages
✅ Easy-to-use struct-based validation

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📌 Installation

To use GoValidator, install it as a Go module:

  go get github.com/devjefster/GoValidator@latest

📌 Usage Example

Create a struct with validation tags and run the validator.

package main

import (
	"fmt"
	"github.com/devjefster/GoValidator/validator"
)

type User struct {
	Username      string   `validate:"required,minSize=3,maxSize=15"`
	Email         string   `validate:"required,email"`
	Age           int      `validate:"required,positive"`
	Balance       float64  `validate:"positiveOrZero"`
	IsActive      bool     `validate:"isTrue"`
	Tags          []string `validate:"minSize=1,maxSize=5"`
	Birthdate     string   `validate:"date=2006-01-02,pastInclusive=2006-01-02"`
	Subscription  string   `validate:"date=2006-01-02,future=2006-01-02"`
	PhoneNumbers  []string `validate:"size=2"`
	Comment       string   `validate:"maxSize=200"`
	FavoriteItems []int    `validate:"minSize=2"`
}

func main() {
	user := User{
		Username:      "johndoe",
		Email:         "johndoe@example.com",
		Age:           25,
		Balance:       100.50,
		IsActive:      true,
		Tags:          []string{"Go", "Golang"},
		Birthdate:     "1995-06-15",
		Subscription:  "2025-01-01",
		PhoneNumbers:  []string{"123-456-7890", "987-654-3210"},
		Comment:       "This is a sample comment.",
		FavoriteItems: []int{1, 2},
	}

	errors := validator.Validate(user)

	if errors.HasErrors() {
		fmt.Println("Validation failed:")
		for _, err := range errors {
			fmt.Println("-", err)
		}
	} else {
		fmt.Println("Validation passed ✅")
	}
}

📌 Supported Validation Rules

Rule	Description	Example
required	Ensures the field is not empty or nil.	validate:"required"
email	Ensures the field contains a valid email.	validate:"email"
isTrue	Ensures the field is true.	validate:"isTrue"
positive	Ensures the field is greater than 0.	validate:"positive"
negative	Ensures the field is less than 0.	validate:"negative"
positiveOrZero	Ensures the field is >= 0.	validate:"positiveOrZero"
negativeOrZero	Ensures the field is <= 0.	validate:"negativeOrZero"
size=n	Ensures the collection has exactly n elements.	validate:"size=2"
minSize=n	Ensures the collection has at least n elements.	validate:"minSize=2"
maxSize=n	Ensures the collection has at most n elements.	validate:"maxSize=5"
date=format	Ensures the field is a valid date in the given format.	validate:"date=2006-01-02"
past=format	Ensures the field is a past date.	validate:"past=2006-01-02"
future=format	Ensures the field is a future date.	validate:"future=2006-01-02"
pastInclusive=format	Ensures the field is a past or present date.	validate:"pastInclusive=2006-01-02"
futureInclusive=format	Ensures the field is a future or present date.	validate:"futureInclusive=2006-01-02"

📌 Running Tests

To run all unit tests:

  go test -v ./...

📌 Contributions

Feel free to fork, contribute, and open issues to improve this library! 🚀

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✅ Summary

✅ Detailed documentation with examples
✅ List of all supported validation rules
✅ Installation and test instructions
✅ Encourages contributions and improvements