Accessing Graph Structure

The read-only graph structure can be accessed via the graph property of the canvas.

    
const element = document.getElementById('canvas');

const canvas = new CanvasBuilder(element)
  .build();

canvas.graph.getAllNodeIds().forEach(nodeId => {
  console.log(canvas.graph.getNode(nodeId));
});

  

The graph object provides all the necessary methods to retrieve the structure of the current graph.

Nodes

1. get the state of a node

       
   const node = canvas.graph.getNode("node-1");
   
     

   This method returns null if the node does not exist.

2. get the IDs of all nodes

       
   const nodeIds = canvas.graph.getAllNodeIds();
   
     

3. get the IDs of all ports for a specific node

       
   const portIds = canvas.graph.getNodePortIds("node-1");
   
     

   This method returns null if the node does not exist.

4. get the IDs of incoming edges for a specific node

       
   const edgeIds = canvas.graph.getNodeIncomingEdgeIds("node-1");
   
     

   This method returns null if the node does not exist.

5. get the IDs of outgoing edges for a specific node

       
   const edgeIds = canvas.graph.getNodeOutgoingEdgeIds("node-1");
   
     

   This method returns null if the node does not exist.

6. get the IDs of cycle edges for a specific node

       
   const edgeIds = canvas.graph.getNodeCycleEdgeIds("node-1");
   
     

   This method returns null if the node does not exist. Note: A cycle edge is one where the source port and target port are the same. Therefore, edges with the same source and target node are not necessarily cycle edges.

7. get the IDs of adjacent edges for a specific node

       
   const edgeIds = canvas.graph.getNodeAdjacentEdgeIds("node-1");
   
     

   This method returns null if the node does not exist.

8. get node ID for a specific HTMLElement

       
   const nodeId = canvas.graph.getElementNodeId(nodeElement);
   
     

   This method returns null if specified element is not a node.

Ports

1. get the state of a port

       
   const port = canvas.graph.getPort("port-1");
   
     

   This method returns null if the port does not exist.

2. get the IDs of all ports

       
   const portIds = canvas.graph.getAllPortIds();
   
     

3. get the IDs of incoming edges for a specific port

       
   const edgeIds = canvas.graph.getPortIncomingEdgeIds("port-1");
   
     

   This method returns null if the port does not exist.

4. get the IDs of outgoing edges for a specific port

       
   const edgeIds = canvas.graph.getPortOutgoingEdgeIds("port-1");
   
     

   This method returns null if the port does not exist.

5. get the IDs of cycle edges for a specific port

       
   const edgeIds = canvas.graph.getPortCycleEdgeIds("port-1");
   
     

   This method returns null if the port does not exist.

6. get the IDs of adjacent edges for a specific port

       
   const edgeIds = canvas.graph.getPortAdjacentEdgeIds("port-1");
   
     

   This method returns null if the port does not exist.

7. get all port IDs attached to a specific HTMLElement

       
   const portIds = canvas.graph.getElementPortIds(portElement);
   
     

Edges

1. get the IDs of all edges

       
   const edgeIds = canvas.graph.getAllEdgeIds();
   
     

2. get the state of an edge

       
   const edge = canvas.graph.getEdge("edge-1");
   
     

   This method returns null if the edge does not exist.