refactor(elements): simplfy node and edge handling

src/EdgeRenderer/EdgeTypes/BezierEdge.js

@@ -1,6 +1,6 @@
-import React from 'react';
+import React, { memo } from 'react';
 
-export default (props) => {
+export default memo((props) => {
   const { targetNode, sourceNode } = props;
   const style = props.style || {};
 
@@ -26,4 +26,4 @@ export default (props) => {
       d={dAttr}
     />
   );
-};
+});

src/EdgeRenderer/EdgeTypes/StraightEdge.js

@@ -1,6 +1,6 @@
-import React from 'react';
+import React, { memo } from 'react';
 
-export default (props) => {
+export default memo((props) => {
   const { targetNode, sourceNode } = props;
   const style = props.style || {};
 
@@ -20,4 +20,4 @@ export default (props) => {
       d={`M ${sourceX},${sourceY}L ${targetX},${targetY}`}
     />
   );
-};
+});

src/EdgeRenderer/index.js

@@ -21,6 +21,7 @@ function renderEdge(e, props, graphContext) {
   return (
     <EdgeComponent
       key={`${e.source}-${e.target}`}
+      id={e.id}
       type={e.type}
       sourceNode={sourceNode}
       targetNode={targetNode}

src/GraphContext/index.js

@@ -1,14 +1,16 @@
-import React, { createContext, useEffect, useReducer, useRef } from 'react';
+import React, { createContext, useEffect, useReducer } from 'react';
 import PropTypes from 'prop-types';
 import isEqual from 'lodash.isequal';
 
 import { reducer, initialState } from '../state';
 import { setNodes, setEdges } from '../state/actions';
+import { parseElement, isNode, isEdge } from '../graph-utils';
 
 export const GraphContext = createContext({});
 
 export const Provider = (props) => {
   const {
+    elements,
     children,
     onConnect
   } = props;
@@ -16,7 +18,10 @@ export const Provider = (props) => {
   const [state, dispatch] = useReducer(reducer, initialState);
 
   useEffect(() => {
-    const nextNodes = props.nodes.map(propNode => {
+    const nodes = elements.filter(isNode);
+    const edges = elements.filter(isEdge).map(parseElement);
+
+    const nextNodes = nodes.map(propNode => {
       const existingNode = state.nodes.find(n => n.id === propNode.id);
 
       if (existingNode) {
@@ -29,22 +34,21 @@ export const Provider = (props) => {
         };
       }
 
-      return propNode;
+      return parseElement(propNode);
     });
 
     const nodesChanged = !isEqual(state.nodes, nextNodes);
-    const edgesChanged = !isEqual(state.edges, props.edges);
+    const edgesChanged = !isEqual(state.edges, edges);
 
     if (nodesChanged) {
       dispatch(setNodes(nextNodes));
     }
 
     if (edgesChanged) {
-      dispatch(setEdges(props.edges));
+      dispatch(setEdges(edges));
     }
   });
 
-
   const graphContext = {
     state,
     dispatch,
@@ -63,11 +67,9 @@ export const Provider = (props) => {
 export const { Consumer } = GraphContext;
 
 Provider.propTypes = {
-  nodes: PropTypes.arrayOf(PropTypes.object),
-  edges: PropTypes.arrayOf(PropTypes.object)
+  elements: PropTypes.arrayOf(PropTypes.object)
 };
 
 Provider.defaultProps = {
-  nodes: [],
-  edges: []
+  elements: [],
 };

src/NodeRenderer/NodeTypes/wrapNode.js

@@ -66,7 +66,7 @@ const onNodeClick = (evt, { onClick, dispatch, id, type, position, data }) => {
 
   const node = { id, type, position, data }
 
-  dispatch(setSelectedElements(node));
+  dispatch(setSelectedElements({ id, type }));
   onClick(node);
 };
 

src/NodeRenderer/index.js

@@ -25,6 +25,7 @@ function renderNode(d, props, graphContext) {
       transform={graphContext.state.transform}
       getNodeById={graphContext.getNodeById}
       selectedElements={graphContext.state.selectedElements}
+      style={d.style}
     />
   );
 }

src/ReactGraph/index.js

@@ -1,12 +1,10 @@
 import React, { PureComponent } from 'react';
-import isEqual from 'lodash.isequal';
 
 if (process.env.NODE_ENV !== 'production') {
   const whyDidYouRender = require('@welldone-software/why-did-you-render');
   whyDidYouRender(React);
 }
 
-import { parseElements, isNode, isEdge } from '../graph-utils';
 import GraphView from '../GraphView';
 import GlobalKeyHandler from '../GlobalKeyHandler';
 import { Provider } from '../GraphContext';
@@ -28,42 +26,18 @@ class ReactGraph extends PureComponent {
 
     this.nodeTypes = createNodeTypes(props.nodeTypes);
     this.edgeTypes = createEdgeTypes(props.edgeTypes);
-
-    this.state = {
-      nodes: [],
-      edges: []
-    };
-  }
-
-  componentDidMount() {
-    this.updateElements(this.props.elements);
-  }
-
-  componentDidUpdate(prevProps) {
-    if (!isEqual(prevProps.elements, this.props.elements)) {
-      this.updateElements(this.props.elements);
-    }
-  }
-
-  updateElements(elements) {
-    const parsedElements = elements.map(parseElements);
-
-    this.setState({
-      nodes: parsedElements.filter(isNode),
-      edges: parsedElements.filter(isEdge),
-    });
   }
 
   render() {
     const {
-      style, onElementClick, children, onLoad,
+      style, onElementClick, elements, children, onLoad,
       onMove, onChange, onElementsRemove, onConnect, onNodeDragStop,
       connectionLineType, connectionLineStyle
     } = this.props;
 
     return (
       <div style={style} className="react-graph">
-        <Provider nodes={this.state.nodes} edges={this.state.edges} onConnect={onConnect}>
+        <Provider elements={elements} onConnect={onConnect}>
           <GraphView
             onLoad={onLoad}
             onMove={onMove}

src/graph-utils.js

@@ -23,15 +23,13 @@ export const removeElements = (elements, elementsToRemove) => {
   });
 };
 
-let internalNodeId = 0;
+const getEdgeId = (e) => `react-graph__edge-${e.source}-${e.target}`;
 
-const getId = () => internalNodeId++;
-
-export const parseElements = (e) => {
+export const parseElement = (e) => {
   e.type = e.type || 'default';
-  e.id = e.id ? e.id : getId();
 
   if (isEdge(e)) {
+    e.id = e.id ? e.id.toString() : getEdgeId(e);
     return e;
   }
 
@@ -132,5 +130,6 @@ export default {
   separateElements,
   getBoundingBox,
   graphPosToZoomedPos,
-  getConnectedEdges
+  getConnectedEdges,
+  parseElement
 };

src/index.js

@@ -5,7 +5,7 @@ export default ReactGraph;
 export { default as SourceHandle } from './NodeRenderer/HandleTypes/SourceHandle';
 export { default as TargetHandle } from './NodeRenderer/HandleTypes/TargetHandle';
 
-export  {
+export {
   isNode,
   isEdge,
   removeElements,

src/state/index.js

@@ -1,4 +1,5 @@
 import { zoomIdentity } from 'd3-zoom';
+import isEqual from 'lodash.isequal';
 
 import { getBoundingBox, getNodesInside, getConnectedEdges } from '../graph-utils';
 
@@ -101,10 +102,13 @@ export const reducer = (state, action) => {
       const selectedNodes = getNodesInside(state.nodes, action.payload.selection, state.transform);
       const selectedEdges = getConnectedEdges(selectedNodes, state.edges);
 
+      const nextSelectedElements =  [...selectedNodes, ...selectedEdges];
+      const selectedElementsUpdated = !isEqual(nextSelectedElements, state.selectedElements);
+
       return {
         ...state,
         ...action.payload,
-        selectedElements: [...selectedNodes, ...selectedEdges]
+        selectedElements: selectedElementsUpdated ? nextSelectedElements: state.selectedElements
       };
     }
     case SET_NODES_SELECTION: {