udemy-go-web-2/internal/models/tokens.go

43 lines
924 B
Go

package models
import (
"crypto/rand"
"crypto/sha256"
"encoding/base32"
"time"
)
const (
ScopeAuthentication = "authentication"
)
// Token is the type for authentication tokens
type Token struct {
PlainText string `json:"token"`
UserID int64 `json:"-"`
Hash []byte `json:"-"`
Expiry time.Time `json:"expiry"`
Scope string `json:"-"`
}
// GenerateToken Generates a token that lasts for ttl, and returns it
func GenerateToken(userID int, ttl time.Duration, scope string) (*Token, error) {
token := &Token{
UserID: int64(userID),
Expiry: time.Now().Add(ttl),
Scope: scope,
}
randomBytes := make([]byte, 16)
_, err := rand.Read(randomBytes)
if err != nil {
return nil, err
}
token.PlainText = base32.StdEncoding.WithPadding((base32.NoPadding)).
EncodeToString((randomBytes))
hash := sha256.Sum256([]byte(token.PlainText))
token.Hash = hash[:]
return token, nil
}