Adds LDAP auth support

backend/internal/entity/setting/auth_methods.go

@@ -0,0 +1,20 @@
+package setting
+
+import (
+	"encoding/json"
+)
+
+// GetAuthMethods returns the authentication methods enabled for this site
+func GetAuthMethods() ([]string, error) {
+	var l []string
+	var m Model
+	if err := m.LoadByName("auth-methods"); err != nil {
+		return l, err
+	}
+
+	if err := json.Unmarshal([]byte(m.Value.String()), &l); err != nil {
+		return l, err
+	}
+
+	return l, nil
+}