Fatal error: Uncaught Error: Class 'JsonSchema\Constraints\Constraint' not found in /data/htmlwww/common/jpgraph/vendor/justinrainbow/json-schema/src/JsonSchema/Constraints/CollectionConstraint.php:20 Stack trace: #0 {main} thrown in /data/htmlwww/common/jpgraph/vendor/justinrainbow/json-schema/src/JsonSchema/Constraints/CollectionConstraint.php on line 20