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Connection Validation

Connections can be validated before edges are created and nodes get connected.

Using a handle in a custom node

<div>
  [ ... ]

  <Handle type="source" :is-valid-connection="isValidConnection" />
</div>

Passing as node option

const nodes = [
  {
    id: '1',
    label: 'Node 1',
    position: { x: 0, y: 0 },
    isValidSourcePos: (connection) => {
      return connection.target === '2'
    },
  },
]