Initial commit of auth package.

auth/auth.go

@@ -0,0 +1,60 @@
+package auth
+
+import (
+	"errors"
+
+	"github.com/labstack/echo-contrib/session"
+	"github.com/labstack/echo/v4"
+	"golang.org/x/crypto/bcrypt"
+)
+
+const (
+	sessionName             = "ua"
+	sessionKeyUserID        = "user_id"
+	sessionKeyAuthenticated = "authenticated"
+)
+
+func Login(c echo.Context, userID int) error {
+	sess, err := session.Get(sessionName, c)
+	if err != nil {
+		return err
+	}
+	sess.Values[sessionKeyUserID] = userID
+	sess.Values[sessionKeyAuthenticated] = true
+	// TODO: max age?
+	return sess.Save(c.Request(), c.Response())
+}
+
+func Logout(c echo.Context) error {
+	sess, err := session.Get(sessionName, c)
+	if err != nil {
+		return err
+	}
+	sess.Values[sessionKeyAuthenticated] = false
+	return sess.Save(c.Request(), c.Response())
+}
+
+func GetUserID(c echo.Context) (int, error) {
+	sess, err := session.Get(sessionName, c)
+	if err != nil {
+		return 0, err
+	}
+
+	if sess.Values[sessionKeyAuthenticated] == true {
+		return sess.Values[sessionKeyUserID].(int), nil
+	}
+
+	return 0, errors.New("user not authenticated")
+}
+
+func HashPassword(password string) (string, error) {
+	hash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	if err != nil {
+		return "", err
+	}
+	return string(hash), nil
+}
+
+func CheckPassword(password, hash string) error {
+	return bcrypt.CompareHashAndPassword([]byte(hash), []byte(password))
+}