Fatal error: Uncaught Error: Interface 'SAML2\Signature\ValidatorInterface' not found in /var/www/alldocs/home/sdoehner/webtest/simplesamlphp_idp/vendor/simplesamlphp/saml2/src/SAML2/Signature/ValidatorChain.php:18 Stack trace: #0 {main} thrown in /var/www/alldocs/home/sdoehner/webtest/simplesamlphp_idp/vendor/simplesamlphp/saml2/src/SAML2/Signature/ValidatorChain.php on line 18