Merge pull request #3681 from xyflow/svelte-on-edge-creation

feat(svelte) added onedgecreate function

examples/svelte/src/routes/examples/edges/+page.svelte

@@ -6,7 +6,8 @@
 		Background,
 		BackgroundVariant,
 		MiniMap,
-		MarkerType
+		MarkerType,
+		type Connection
 	} from '@xyflow/svelte';
 
 	import '@xyflow/svelte/dist/style.css';
@@ -143,9 +144,28 @@
 			}
 		}
 	]);
+
+	$: console.log('edges', $edges);
+
+	function getEdgeId(connection: Connection) {
+		return `edge-${connection.source}-${connection.target}}`;
+	}
 </script>
 
-<SvelteFlow {nodes} {edges} fitView nodeDragThreshold={2}>
+<SvelteFlow
+	{nodes}
+	{edges}
+	fitView
+	nodeDragThreshold={2}
+	onedgecreate={(connection) => {
+		console.log('on edge create', connection);
+
+		return {
+			...connection,
+			id: getEdgeId(connection)
+		};
+	}}
+>
 	<Controls />
 	<Background variant={BackgroundVariant.Dots} />
 	<MiniMap />

packages/svelte/src/lib/components/Handle/Handle.svelte

@@ -55,6 +55,7 @@
     isValidConnection,
     lib,
     addEdge,
+    onedgecreate,
     panBy,
     cancelConnection,
     updateConnection,
@@ -80,8 +81,13 @@
         cancelConnection,
         panBy,
         onConnect: (connection) => {
-          addEdge(connection);
+          const edge = $onedgecreate ? $onedgecreate(connection) : connection;
 
+          if (!edge) {
+            return;
+          }
+
+          addEdge(edge);
           // @todo: should we change/ improve the stuff we are passing here?
           // instead of source/target we could pass fromNodeId, fromHandleId, etc
           dispatch('connect', { connection });

packages/svelte/src/lib/container/SvelteFlow/SvelteFlow.svelte

@@ -71,6 +71,7 @@
   export let autoPanOnNodeDrag: $$Props['autoPanOnNodeDrag'] = true;
   export let onerror: $$Props['onerror'] = undefined;
   export let ondelete: $$Props['ondelete'] = undefined;
+  export let onedgecreate: $$Props['onedgecreate'] = undefined;
   export let attributionPosition: $$Props['attributionPosition'] = undefined;
   export let proOptions: $$Props['proOptions'] = undefined;
   export let defaultEdgeOptions: $$Props['defaultEdgeOptions'] = undefined;
@@ -149,6 +150,7 @@
       autoPanOnNodeDrag,
       onerror,
       ondelete,
+      onedgecreate,
       connectionMode,
       nodeDragThreshold
     };

packages/svelte/src/lib/container/SvelteFlow/types.ts

@@ -26,7 +26,8 @@ import type {
   EdgeTypes,
   DefaultEdgeOptions,
   FitViewOptions,
-  OnDelete
+  OnDelete,
+  OnEdgeCreate
 } from '$lib/types';
 import type { Writable } from 'svelte/store';
 
@@ -89,4 +90,6 @@ export type SvelteFlowProps = DOMAttributes<HTMLDivElement> & {
   onMoveEnd?: OnMoveEnd;
   onerror?: OnError;
   ondelete?: OnDelete;
+
+  onedgecreate?: OnEdgeCreate;
 };

packages/svelte/src/lib/container/SvelteFlow/utils.ts

@@ -64,6 +64,7 @@ export type UpdatableStoreProps = {
   connectionMode?: UnwrapWritable<SvelteFlowStore['connectionMode']>;
   onerror?: UnwrapWritable<SvelteFlowStore['onerror']>;
   ondelete?: UnwrapWritable<SvelteFlowStore['ondelete']>;
+  onedgecreate?: UnwrapWritable<SvelteFlowStore['onedgecreate']>;
   nodeDragThreshold?: UnwrapWritable<SvelteFlowStore['nodeDragThreshold']>;
 };
 

packages/svelte/src/lib/store/initial-store.ts

@@ -35,7 +35,8 @@ import type {
   Node,
   Edge,
   FitViewOptions,
-  OnDelete
+  OnDelete,
+  OnEdgeCreate
 } from '$lib/types';
 import { createNodesStore, createEdgesStore } from './utils';
 import { initConnectionProps, type ConnectionProps } from './derived-connection-props';
@@ -130,6 +131,7 @@ export const getInitialStore = ({
     lib: readable<string>('svelte'),
     onlyRenderVisibleElements: writable<boolean>(false),
     onerror: writable<OnError>(devWarn),
-    ondelete: writable<OnDelete>(undefined)
+    ondelete: writable<OnDelete>(undefined),
+    onedgecreate: writable<OnEdgeCreate>(undefined)
   };
 };

packages/svelte/src/lib/types/general.ts

@@ -4,7 +4,8 @@ import type {
   HandleType,
   Position,
   XYPosition,
-  ConnectingHandle
+  ConnectingHandle,
+  Connection
 } from '@xyflow/system';
 
 import type { Node } from './nodes';
@@ -35,3 +36,4 @@ export type HandleComponentProps = {
 export type FitViewOptions = FitViewOptionsBase<Node>;
 
 export type OnDelete = (params: { nodes: Node[]; edges: Edge[] }) => void;
+export type OnEdgeCreate = (connection: Connection) => Edge | Connection | void;

packages/system/src/utils/edges/general.ts

@@ -112,7 +112,7 @@ export function isEdgeVisible({ sourceNode, targetNode, width, height, transform
 }
 
 const getEdgeId = ({ source, sourceHandle, target, targetHandle }: Connection | EdgeBase): string =>
-  `xyflow__edge-${source}${sourceHandle || ''}-${target}${targetHandle || ''}`;
+  `xy-edge__${source}${sourceHandle || ''}-${target}${targetHandle || ''}`;
 
 const connectionExists = (edge: EdgeBase, edges: EdgeBase[]) => {
   return edges.some(
@@ -148,6 +148,14 @@ export const addEdgeBase = <EdgeType extends EdgeBase>(
     return edges;
   }
 
+  if (edge.sourceHandle === null) {
+    delete edge.sourceHandle;
+  }
+
+  if (edge.targetHandle === null) {
+    delete edge.targetHandle;
+  }
+
   return edges.concat(edge);
 };