validate/input.go

package validate

import (
	"reflect"
	"regexp"
	"strconv"
)

// InputFunc is a function that converts the parameter of a validation rule to the desired type
type InputFunc func(reflect.Kind, string) interface{}

// InputInt always returns an int
func InputInt(kind reflect.Kind, value string) interface{} {
	return int(InputSame(reflect.Int, value).(int64))
}

// InputRegexp always returns a compiled regular expression
func InputRegexp(kind reflect.Kind, value string) interface{} {
	return regexp.MustCompile(value)
}

// InputSame returns the type matching the field
func InputSame(kind reflect.Kind, value string) interface{} {
	var val interface{}
	var err error

	switch kind {
	case reflect.String:
		val = value
	case reflect.Int:
		val, err = strconv.ParseInt(value, 10, 64)
	case reflect.Uint:
		val, err = strconv.ParseUint(value, 10, 64)
	case reflect.Float64:
		val, err = strconv.ParseFloat(value, 64)
	case reflect.Bool:
		val, err = strconv.ParseBool(value)
	default:
		panic(`Cannot pass value to checks on type ` + kind.String())
	}

	if err != nil {
		panic(`Invalid value "` + value + `"`)
	}

	return val
}