Workflow Diagram: "edge merging" (new edge creation)

.prettierignore

@@ -0,0 +1 @@
+assets/vendor

assets/js/workflow-diagram/WorkflowDiagram.tsx

@@ -1,17 +1,21 @@
 import React, { useCallback, useEffect, useRef, useState } from 'react';
 import ReactFlow, {
+  Controls,
+  ControlButton,
   NodeChange,
   ReactFlowInstance,
   ReactFlowProvider,
   applyNodeChanges,
 } from 'reactflow';
 import { useStore, StoreApi } from 'zustand';
 import { shallow } from 'zustand/shallow';
+import { ViewfinderCircleIcon, XMarkIcon } from '@heroicons/react/24/outline';
 
 import layout from './layout';
 import nodeTypes from './nodes';
 import edgeTypes from './edges';
 import usePlaceholders from './usePlaceholders';
+import useConnect from './useConnect';
 import fromWorkflow from './util/from-workflow';
 import throttle from './util/throttle';
 import updateSelectionStyles from './util/update-selection';
@@ -39,6 +43,8 @@ export default React.forwardRef<HTMLElement, WorkflowDiagramProps>(
 
     const [model, setModel] = useState<Flow.Model>({ nodes: [], edges: [] });
 
+    const [autofit, setAutofit] = useState<boolean>(true);
+
     const updateSelection = useCallback(
       (id?: string | null) => {
         id = id || null;
@@ -96,10 +102,12 @@ export default React.forwardRef<HTMLElement, WorkflowDiagramProps>(
 
         if (layoutId) {
           chartCache.current.lastLayout = layoutId;
-          layout(newModel, setModel, flow, 300).then(positions => {
-            // Note we don't update positions until the animation has finished
-            chartCache.current.positions = positions;
-          });
+          layout(newModel, setModel, flow, { duration: 300, autofit }).then(
+            positions => {
+              // Note we don't update positions until the animation has finished
+              chartCache.current.positions = positions;
+            }
+          );
         } else {
           // If layout is id, ensure nodes have positions
           // This is really only needed when there's a single trigger node
@@ -184,6 +192,8 @@ export default React.forwardRef<HTMLElement, WorkflowDiagramProps>(
       }
     }, [flow, ref]);
 
+    const connectHandlers = useConnect(model, setModel, store);
+
     return (
       <ReactFlowProvider>
         <ReactFlow
@@ -201,7 +211,19 @@ export default React.forwardRef<HTMLElement, WorkflowDiagramProps>(
           deleteKeyCode={null}
           fitView
           fitViewOptions={{ padding: FIT_PADDING }}
-        />
+          {...connectHandlers}
+        >
+          <Controls showInteractive={false} position="bottom-left">
+            <ControlButton
+              onClick={() => {
+                setAutofit(!autofit);
+              }}
+              title="Automatically fit view"
+            >
+              <ViewfinderCircleIcon style={{ opacity: autofit ? 1 : 0.4 }} />
+            </ControlButton>
+          </Controls>
+        </ReactFlow>
       </ReactFlowProvider>
     );
   }

assets/js/workflow-diagram/components/ErrorMessage.tsx

@@ -0,0 +1,15 @@
+import React from 'react';
+
+import { ExclamationCircleIcon } from '@heroicons/react/24/outline';
+
+const ErrorMessage: React.FC<React.ComponentProps<any>> = ({ children }) => {
+  console.log(children);
+  return (
+    <p className="line-clamp-2 align-left text-xs text-red-500 flex items-center">
+      <ExclamationCircleIcon className="mr-1 w-5" />
+      {children ?? 'An error occurred'}
+    </p>
+  );
+};
+
+export default ErrorMessage;

assets/js/workflow-diagram/components/PathButton.tsx

@@ -0,0 +1,35 @@
+import React from 'react';
+import { Handle } from 'reactflow';
+import { LinkIcon } from '@heroicons/react/24/outline';
+
+function PathButton() {
+  return (
+    <Handle
+      type="source"
+      style={{
+        position: 'relative',
+        height: 24,
+        width: 'auto',
+
+        // These values come from tailwind but have to be set on styles to override reactflow stuff
+        borderRadius: '0.5rem',
+        borderWidth: '0',
+
+        // override react flow stuff
+        transform: 'translate(0,0)',
+        left: 'auto',
+        top: 'auto',
+        cursor: 'pointer',
+      }}
+      className="transition duration-150 ease-in-out pointer-events-auto rounded-lg
+      !bg-indigo-600 hover:!bg-indigo-500 py-1 px-2 text-[0.8125rem] font-semibold leading-5 text-white"
+    >
+      <LinkIcon
+        className="inline h-4 w-4"
+        style={{ marginTop: '-6px', pointerEvents: 'none' }}
+      />
+    </Handle>
+  );
+}
+
+export default PathButton;

assets/js/workflow-diagram/components/PlusButton.tsx

@@ -4,8 +4,9 @@ function PlusButton() {
   return (
     <button
       name="add-node"
-      className="transition duration-150 ease-in-out pointer-events-auto rounded-full
-               bg-indigo-600 py-1 px-4 text-[0.8125rem] font-semibold leading-5 text-white hover:bg-indigo-500"
+      className="transition duration-150 ease-in-out pointer-events-auto rounded-lg
+               bg-indigo-600 py-1 px-2 text-[0.8125rem] font-semibold leading-5 text-white
+               hover:bg-indigo-500 mr-1"
     >
       <svg
         xmlns="http://www.w3.org/2000/svg"

assets/js/workflow-diagram/constants.ts

@@ -1,7 +1,3 @@
 export const FIT_DURATION = 180;
 
-export const FIT_PADDING = 0.3;
-
-export const NODE_WIDTH = 180;
-
-export const NODE_HEIGHT = 40;
+export const FIT_PADDING = 0.2;

assets/js/workflow-diagram/edges/Connection.tsx

@@ -0,0 +1,24 @@
+import React from 'react';
+import { EDGE_COLOR_SELECTED } from '../styles';
+import { BezierEdge } from 'reactflow';
+
+export default props => {
+  const { fromX, fromY, toX, toY } = props;
+  return (
+    <BezierEdge
+      id="tmp"
+      sourceX={fromX}
+      sourceY={fromY}
+      targetX={toX}
+      targetY={toY}
+      animated={true}
+      zIndex={-1}
+      style={{
+        stroke: EDGE_COLOR_SELECTED,
+        strokeWidth: 4,
+        strokeDasharray: '4, 4',
+        opacity: 0.7,
+      }}
+    />
+  );
+};

assets/js/workflow-diagram/edges/Edge.tsx

@@ -1,5 +1,11 @@
 import React, { FC } from 'react';
-import { SmoothStepEdge, EdgeProps, EdgeLabelRenderer } from 'reactflow';
+import {
+  SmoothStepEdge,
+  BezierEdge,
+  Edge,
+  EdgeProps,
+  EdgeLabelRenderer,
+} from 'reactflow';
 import { labelStyles } from '../styles';
 
 const CustomEdge: FC<EdgeProps> = props => {
@@ -12,7 +18,9 @@ const CustomEdge: FC<EdgeProps> = props => {
   const labelY = (sourceY + targetY) / 2;
   return (
     <>
-      <SmoothStepEdge {...stepEdgeProps} />
+      {/* Curvature does nothing?? */}
+      <BezierEdge {...stepEdgeProps} pathOptions={{ curvature: 0 }} />
+      {/* <SmoothStepEdge {...stepEdgeProps} pathOptions={{ borderRadius: 500 }} /> */}
       {label && (
         <EdgeLabelRenderer>
           <div

assets/js/workflow-diagram/layout.ts

@@ -1,44 +1,46 @@
-import { stratify, tree } from 'd3-hierarchy';
+import Dagre from '../../vendor/dagre';
 import { timer } from 'd3-timer';
-import { getRectOfNodes, Node, ReactFlowInstance } from 'reactflow';
+import { getRectOfNodes, ReactFlowInstance } from 'reactflow';
 
-import { FIT_PADDING, NODE_HEIGHT, NODE_WIDTH } from './constants';
+import { FIT_PADDING } from './constants';
 import { Flow, Positions } from './types';
-import { styleItem } from './styles';
 
-const layout = tree<Node>()
-  // the node size configures the spacing between the nodes ([width, height])
-  .nodeSize([200, 200])
-  // this is needed for creating equal space between all nodes
-  .separation(() => 2);
+export type LayoutOpts = { duration: number | false; autofit: boolean };
 
 const calculateLayout = async (
   model: Flow.Model,
   update: (newModel: Flow.Model) => any,
   flow: ReactFlowInstance,
-  duration: number | false = 500
+  options: LayoutOuts = {}
 ): Promise<Positions> => {
   const { nodes, edges } = model;
+  const { duration } = options;
+
+  const g = new Dagre.graphlib.Graph().setDefaultEdgeLabel(() => ({}));
+  g.setGraph({
+    rankdir: 'TB',
+    // nodesep: 400,
+    // edgesep: 200,
+    // ranksep: 400,
+  });
+
+  edges.forEach(edge => g.setEdge(edge.source, edge.target));
+  nodes.forEach(node =>
+    g.setNode(node.id, { ...node, width: 350, height: 200 })
+  );
+
+  Dagre.layout(g, { disableOptimalOrderHeuristic: true });
+
+  const newModel = {
+    nodes: nodes.map(node => {
+      const { x, y, width, height } = g.node(node.id);
+
+      return { ...node, position: { x, y }, width, height };
+    }),
+    edges,
+  };
 
-  const hierarchy = stratify<Node>()
-    .id(d => d.id)
-    // get the id of each node by searching through the edges
-    // this only works if every node has one connection
-    .parentId(d => edges.find(e => e.target === d.id)?.source)(nodes);
-
-  // run the layout algorithm with the hierarchy data structure
-  const root = layout(hierarchy);
-  const newNodes = root.descendants().map(d => ({
-    ...d.data,
-    position: { x: d.x, y: d.y },
-    // Ensure nodes have a width/height so that we can later do a fit to bounds
-    width: NODE_WIDTH,
-    height: NODE_HEIGHT,
-  }));
-
-  const newModel = { nodes: newNodes, edges };
-
-  const finalPositions = newNodes.reduce((obj, next) => {
+  const finalPositions = newModel.nodes.reduce((obj, next) => {
     obj[next.id] = next.position;
     return obj;
   }, {} as Positions);
@@ -47,7 +49,7 @@ const calculateLayout = async (
 
   // If the old model had no positions, this is a first load and we should not animate
   if (hasOldPositions && duration) {
-    await animate(model, newModel, update, flow, duration);
+    await animate(model, newModel, update, flow, options);
   } else {
     update(newModel);
   }
@@ -62,8 +64,9 @@ export const animate = (
   to: Flow.Model,
   setModel: (newModel: Flow.Model) => void,
   flowInstance: ReactFlowInstance,
-  duration = 500
+  options: LayoutOpts
 ) => {
+  const { duration = 500, autofit = true } = options;
   return new Promise<void>(resolve => {
     const transitions = to.nodes.map(node => {
       // We usually animate a node from its previous position
@@ -85,7 +88,7 @@ export const animate = (
 
     // create a timer to animate the nodes to their new positions
     const t = timer((elapsed: number) => {
-      const s = elapsed / duration;
+      const s = elapsed / (duration || 0);
 
       const currNodes = transitions.map(({ node, from, to }) => ({
         ...node,
@@ -100,7 +103,9 @@ export const animate = (
       if (isFirst) {
         // Synchronise a fit to the final position with the same duration
         const bounds = getRectOfNodes(to.nodes);
-        flowInstance.fitBounds(bounds, { duration, padding: FIT_PADDING });
+        if (autofit) {
+          flowInstance.fitBounds(bounds, { duration, padding: FIT_PADDING });
+        }
         isFirst = false;
       }
 

assets/js/workflow-diagram/nodes/Job.tsx

@@ -1,7 +1,8 @@
-import React, { memo, useEffect, useState } from 'react';
+import React, { memo } from 'react';
 import { Position, NodeProps } from 'reactflow';
 import Node from './Node';
 import PlusButton from '../components/PlusButton';
+import PathButton from '../components/PathButton';
 import getAdaptorName from '../util/get-adaptor-name';
 import useAdaptorIcons, { AdaptorIconData } from '../useAdaptorIcons';
 
@@ -12,7 +13,9 @@ const JobNode = ({
   sourcePosition = Position.Bottom,
   ...props
 }: NodeProps<NodeData>) => {
-  const toolbar = () => props.data?.allowPlaceholder && <PlusButton />;
+  const toolbar = () => [
+    props.data?.allowPlaceholder && [<PlusButton />, <PathButton />],
+  ];
 
   const adaptorIconsData = useAdaptorIcons();
 
@@ -25,9 +28,10 @@ const JobNode = ({
       label={props.data?.name}
       primaryIcon={icon}
       sublabel={adaptor}
+      isConnectable={true}
       targetPosition={targetPosition}
       sourcePosition={sourcePosition}
-      allowSource
+      // allowSource
       toolbar={toolbar}
       errors={props.data?.errors}
     />