a-was/go-validator

Go struct validation library

Another Go validation library

Usage

package main

import (
	"fmt"

	"github.com/a-was/go-validator"
)

type MyStruct struct {
	Email string `flags:"required"`
	Name  string `regex:"^[a-z]+$"`
	Min   int    `min:"10" max:"20"`
	Max   int    `min:"10" max:"20"`
	Env   string `env:"MYAPP_SETTING" default:"default_value"`
}

func main() {
	myStruct := MyStruct{
		Email: "",
		Name:  "invalid-regex@example.com",
		Min:   5,
		Max:   30,
		Env:   "",
	}
	err := validator.Validate(&myStruct)
	fmt.Println(err)
	// Output:
	// Email: required value not filled
	// Name: invalid value: invalid-regex@example.com does not match regex ^[a-z]+$
	// Min: invalid value: 5, minimum value is 10
	// Max: invalid value: 30, maximum value is 20
}

Avaliable tags

Tags can be combined with each other

min

Takes integer as value
For numeric types (int, uint, etc...) it checks if property value is grater or equal than value specyfied in tag
For string, map, slice types it checks len

max

Same as min, but checks if property value if lower or equal

regex

Takes regex string as value
Checks if string matches provided regex

flags

Takes list of supported flags as value

Supported flags

• required - means that property value cannot be zero-value or nil

env

Takes environment variable name as value
If property value is zero-value or nil, it sets its value to the value of the environment variable

default

Takes default value as value
If property value is zero-value or nil, it sets its value to value specyfied in tag