feat(edges): add label props

src/components/Edges/StraightEdge.tsx

@@ -1,11 +1,32 @@
 import React, { memo } from 'react';
 
+import EdgeText from './EdgeText';
 import { EdgeProps } from '../../types';
 
 export default memo(
-  ({ sourceX, sourceY, targetX, targetY, style = {} }: EdgeProps) => {
+  ({ sourceX, sourceY, targetX, targetY, label, labelStyle, labelShowBg, labelBgStyle, style = {} }: EdgeProps) => {
+    const yOffset = Math.abs(targetY - sourceY) / 2;
+    const centerY = targetY < sourceY ? targetY + yOffset : targetY - yOffset;
+
+    const xOffset = Math.abs(targetX - sourceX) / 2;
+    const centerX = targetX < sourceX ? targetX + xOffset : targetX - xOffset;
+
+    const text = label ? (
+      <EdgeText
+        x={centerX}
+        y={centerY}
+        label={label}
+        labelStyle={labelStyle}
+        labelShowBg={labelShowBg}
+        labelBgStyle={labelBgStyle}
+      />
+    ) : null;
+
     return (
-      <path {...style} d={`M ${sourceX},${sourceY}L ${targetX},${targetY}`} />
+      <g>
+        <path style={style} className="react-flow__edge-path" d={`M ${sourceX},${sourceY}L ${targetX},${targetY}`} />
+        {text}
+      </g>
     );
   }
 );