default_validator.go

package jwt

import (
	"errors"
	"time"
)

type DefaultValidator struct {
	now       func() time.Time
	audiences map[string]struct{}
}

func NewDefaultValidator(audiences ...string) DefaultValidator {
	allowed := make(map[string]struct{}, len(audiences))
	for _, audience := range audiences {
		allowed[audience] = struct{}{}
	}
	return DefaultValidator{now: time.Now, audiences: allowed}
}

func (this DefaultValidator) Validate(claim interface{}) error {
	if expiration, ok := claim.(TokenExpiration); !this.isCurrent(expiration, ok) {
		return TokenExpiredErr
	}

	if audience, ok := claim.(TokenAudience); !this.hasAllowedAudience(audience, ok) {
		return InvalidAudienceErr
	}

	return nil
}

func (this DefaultValidator) hasAllowedAudience(claim TokenAudience, hasAudience bool) bool {
	if !hasAudience {
		return true
	}

	_, ok := this.audiences[claim.TokenAudience()]
	return ok
}

func (this DefaultValidator) isCurrent(claim TokenExpiration, hasExpiration bool) bool {
	return !hasExpiration || claim.TokenExpiration().After(this.now())
}

var (
	TokenExpiredErr    = errors.New("the token is expired")
	InvalidAudienceErr = errors.New("the audience is invalid")
)