beautiful-diagram-new-node.js

const MyDiagram = () => {
  // create diagrams schema
  const [schema, setSchema] = useState(initialSchema);
  
  const addNode = () => {
    var new_node = {
      //new node data
    }
    var new_schema = Object.assign({},schema)
    new_schema.nodes.push(new_node)
    setSchema(new_schema)
  }
  
  return (
    <div style={{ height: '22.5rem' }}>
	<button onClick={addNode}>addNode</button>
      	<Diagram schema={schema} onChange={setSchema}/>
    </div>
  );
};