olivere / validation

Validate Go structs.

What is it?

The validation package is a very simple way to validate entities before they e.g. get saved to a data store. It merely collects all errors found and wraps them in the error interface that Go provides. It has some functions to format those errors.

The validation package isn't meant to be used for end-users, so it misses some crucial features like the ability to localize the error messages.

Example:

import (
    "fmt"
	"time"

	"github.com/olivere/validation"
)

type Person struct {
	Name string
	DoB  time.Time
}

func (p Person) Validate() error {
	var errs validation.Errors

	if p.Name == "" {
		errs = errs.Add("Name", "is missing")
	}
	if p.DoB.IsZero() {
		errs = errs.Add("DoB", "is missing")
	}

	if errs.HasErrors() {
		return errs
	}
	return nil
}

func main() {
	p := &Person{}

	err := p.Validate()
	if err != nil {
		fmt.Printf("Validation failed: %v\n", err)
		if errs, ok := err.(validation.Errors); ok {
			fmt.Println(errs.Join(", "))
		}
	}
}

License

MIT. See LICENSE file.