/react-digraph

A library for creating directed graph editors

Primary LanguageJavaScriptMIT LicenseMIT

react-digraph

Demo

Overview

A React component which makes it easy to create a directed graph editor without implementing any of the SVG drawing or event handling logic.

Important v8.0.0 Information

Version 8.0.0 introduces multi-select nodes and edges using Ctrl-Shift-Mouse events (Cmd-Shift-mouse for Mac). This requires a breaking change. Instead of onSelectNode/Edge, you'll only provide one onSelect function callback and a selected object with { nodes: Map, and edges: Map } as the parameter format. The typings folder has the exact type definition for these attributes. When either edges or nodes are selected the onSelect function will fire with the object. You will have to handle all nodes and edges selected, or if there is only one then you will have to determine if it's a node or edge within the onSelect function.

To disable multi-select you can set allowMultiselect to false, which disables the Ctrl-Shift-mouse event, but we will still use the onSelect function. Both onSelectNode and onSelectEdge are deprecated.

Breaking changes:

  • onPasteSelected now accepts a SelectionT object for the first parameter
  • onPasteSelected now accepts an IPoint instead of a XYCoords array for the second parameter.
  • onDeleteSelected is added which takes a SelectionT parameter.
  • onSelect is added, which accepts SelectionT and Event parameters.
  • onUpdateNode accepts a Map of updated nodes in the second parameter (for example, if multiple nodes are moved).
  • selected is a new property to track selected nodes and edges. It is a SelectionT type.
  • canDeleteSelected takes the place of canDeleteNode and canDeleteEdge. It accepts a SelectionT type as a parameter.
  • onDeleteNode is removed
  • onDeleteEdge is removed
  • selectedNode is removed
  • selectedEdge is removed
  • canDeleteNode is removed
  • canDeleteEdge is removed
  • selectedNodes is removed
  • selectedEdges is removed

Installation

npm install --save react-digraph

If you don't have the following peerDependenies, make sure to install them:

npm install --save react react-dom

Usage

The default export is a component called GraphView; it provides a multitude of hooks for various graph editing operations and a set of controls for zooming. Typically, it should be wrapped in a higher order component that supplies various callbacks (onCreateNode, onCreateEdge etc...).

GraphView expects several properties to exist on your nodes and edges. If these types conflict with existing properties on your data, you must transform your data to re-key these properties under different names and to add the expected properties. All nodes and edges can have a type attribute set - nodes also support a subtype attribute. For a full description of node and edge properties, see the sections for INode and IEdge below.

Configuration for nodes and edges can be passed to GraphView via the nodeTypes, nodeSubtypes, and edgeTypes props. Custom SVG elements can be defined here for the node's type/subtype and the edge's type.

It is often convenient to combine these types into a configuration object that can be referred to elsewhere in the application and used to associate events fired from nodes/edges in the GraphView with other actions in the application. Here is an abbreviated example:

import {
  GraphView, // required
  Edge, // optional
  type IEdge, // optional
  Node, // optional
  type INode, // optional
  type LayoutEngineType, // required to change the layoutEngineType, otherwise optional
  BwdlTransformer, // optional, Example JSON transformer
  GraphUtils // optional, useful utility functions
} from 'react-digraph';

const GraphConfig =  {
  NodeTypes: {
    empty: { // required to show empty nodes
      typeText: "None",
      shapeId: "#empty", // relates to the type property of a node
      shape: (
        <symbol viewBox="0 0 100 100" id="empty" key="0">
          <circle cx="50" cy="50" r="45"></circle>
        </symbol>
      )
    },
    custom: { // required to show empty nodes
      typeText: "Custom",
      shapeId: "#custom", // relates to the type property of a node
      shape: (
        <symbol viewBox="0 0 50 25" id="custom" key="0">
          <ellipse cx="50" cy="25" rx="50" ry="25"></ellipse>
        </symbol>
      )
    }
  },
  NodeSubtypes: {},
  EdgeTypes: {
    emptyEdge: {  // required to show empty edges
      shapeId: "#emptyEdge",
      shape: (
        <symbol viewBox="0 0 50 50" id="emptyEdge" key="0">
          <circle cx="25" cy="25" r="8" fill="currentColor"> </circle>
        </symbol>
      )
    }
  }
}

const NODE_KEY = "id"       // Allows D3 to correctly update DOM

class Graph extends Component {

  constructor(props) {
    super(props);

    this.state = {
      graph: sample,
      selected: {}
    }
  }

  /* Define custom graph editing methods here */

  render() {
    const nodes = this.state.graph.nodes;
    const edges = this.state.graph.edges;
    const selected = this.state.selected;

    const NodeTypes = GraphConfig.NodeTypes;
    const NodeSubtypes = GraphConfig.NodeSubtypes;
    const EdgeTypes = GraphConfig.EdgeTypes;

    return (
      <div id='graph' style={styles.graph}>

        <GraphView  ref='GraphView'
                    nodeKey={NODE_KEY}
                    nodes={nodes}
                    edges={edges}
                    selected={selected}
                    nodeTypes={NodeTypes}
                    nodeSubtypes={NodeSubtypes}
                    edgeTypes={EdgeTypes}
                    allowMultiselect={true} // true by default, set to false to disable multi select.
                    onSelect={this.onSelect}
                    onCreateNode={this.onCreateNode}
                    onUpdateNode={this.onUpdateNode}
                    onDeleteNode={this.onDeleteNode}
                    onCreateEdge={this.onCreateEdge}
                    onSwapEdge={this.onSwapEdge}
                    onDeleteEdge={this.onDeleteEdge}/>
      </div>
    );
  }

}

A typical graph that would be stored in the Graph component's state looks something like this:

{
  "nodes": [
    {
      "id": 1,
      "title": "Node A",
      "x": 258.3976135253906,
      "y": 331.9783248901367,
      "type": "empty"
    },
    {
      "id": 2,
      "title": "Node B",
      "x": 593.9393920898438,
      "y": 260.6060791015625,
      "type": "empty"
    },
    {
      "id": 3,
      "title": "Node C",
      "x": 237.5757598876953,
      "y": 61.81818389892578,
      "type": "custom"
    },
    {
      "id": 4,
      "title": "Node C",
      "x": 600.5757598876953,
      "y": 600.81818389892578,
      "type": "custom"
    }
  ],
  "edges": [
    {
      "source": 1,
      "target": 2,
      "type": "emptyEdge"
    },
    {
      "source": 2,
      "target": 4,
      "type": "emptyEdge"
    }
  ]
}

For a detailed example, check out src/examples/graph.js. To run the example:

npm install
npm run example

A webpage will open in your default browser automatically.

  • To add nodes, hold shift and click on the grid.
  • To add edges, hold shift and click/drag to between nodes.
  • To delete a node or edge, click on it and press delete.
  • Click and drag nodes to change their position.
  • To select multiple nodes, press Ctrl+Shift then click and drag the mouse.
  • You may copy and paste selected nodes and edges with Ctrl+C and Ctrl+V
  • Note: On Mac computers, use Cmd instead of Ctrl.

All props are detailed below.

Props

Prop Type Required Notes
nodeKey string true Key for D3 to update nodes(typ. UUID).
nodes Array<INode> true Array of graph nodes.
edges Array<IEdge> true Array of graph edges.
allowCopyEdges boolean false (default false) Allow onCopySelected to be called when an edge is selected without any nodes.
allowMultiselect boolean false (default true) Use Ctrl-Shift-LeftMouse to draw a multiple selection box.
selected object true The currently selected graph entity.
nodeTypes object true Config object of available node types.
nodeSubtypes object true Config object of available node subtypes.
edgeTypes object true Config object of available edge types.
onSelect func false Called when nodes are selected when allowMultiselect is true. Is passed an object with nodes and edges included.
onCreateNode func true Called when a node is created.
onContextMenu func true Called when contextmenu event triggered.
onUpdateNode func true Called when a node is moved.
onCreateEdge func true Called when an edge is created.
onSwapEdge func true Called when an edge 'target' is swapped.
onBackgroundClick func false Called when the background is clicked.
onArrowClicked func false Called when the arrow head is clicked.
onUndo func false A function called when Ctrl-Z is activated. React-digraph does not keep track of actions, this must be implemented in the client website.
onCopySelected func false A function called when Ctrl-C is activated. React-digraph does not keep track of copied nodes or edges, the this must be implemented in the client website.
onPasteSelected func false A function called when Ctrl-V is activated. React-digraph does not keep track of copied nodes or edges, the this must be implemented in the client website.
canDeleteSelected func false takes the place of canDeleteNode and canDeleteEdge. It accepts a SelectionT type as a parameter. It is called before a node or edge is deleted. The function should return a boolean.
canCreateEdge func false Called before an edge is created.
canSwapEdge func false Called before an edge 'target' is swapped.
afterRenderEdge func false Called after an edge is rendered.
renderNode func false Called to render node geometry.
renderNodeText func false Called to render the node text
renderDefs func false Called to render SVG definitions.
renderBackground func false Called to render SVG background.
readOnly bool false Disables all graph editing interactions.
disableBackspace bool false Disables using backspace to delete the selected node.
maxTitleChars number false Truncates node title characters.
gridSize number false Overall grid size.
gridSpacing number false Grid spacing.
gridDotSize number false Grid dot size.
minZoom number false Minimum zoom percentage.
maxZoom number false Maximum zoom percentage.
nodeSize number false Node bbox size.
edgeHandleSize number false Edge handle size.
edgeArrowSize number false Edge arrow size in pixels. Default 8. Set to 0 to hide arrow.
zoomDelay number false Delay before zoom occurs.
zoomDur number false Duration of zoom transition.
showGraphControls boolean false Whether to show zoom controls.
layoutEngineType typeof LayoutEngineType false Uses a pre-programmed layout engine, such as 'SnapToGrid'
rotateEdgeHandle boolean false Whether to rotate edge handle with edge when a node is moved
centerNodeOnMove boolean false Whether the node should be centered on cursor when moving a node
initialBBox typeof IBBox false If specified, initial render graph using the given bounding box
graphConfig object false dagre graph setting configuration, which will override layout engine graph configuration - only apply to 'HorizontalTree'
nodeSizeOverridesAllowed boolean false Flag to toggle sizeOverride in nodes - only apply to 'HorizontalTree'
nodeLocationOverrides object false Nodes location overrides object - only apply to 'HorizontalTree'

onCreateNode

You have access to d3 mouse event in onCreateNode function.

  onCreateNode = (x, y, mouseEvent) => {
    // we can get the exact mouse position when click happens with this line
    const {pageX, pageY} = mouseEvent;
    // rest of the code for adding a new node ...
  };

Prop Types:

See prop types in the typings folder.

INode

Prop Type Required Notes
anyIDKey string true An id or key for nodes, same as the nodeKey prop
title string true Used in edges and to render the node text.
x number false X coordinate of the node.
y number false Y coordinate of the node.
type string false Node type, for displaying a custom SVG shape.
subtype string false Node subtype, for displaying a custom SVG shape.

title

The title attribute is used for the IDs in the SVG nodes in the graph.

IEdge

Prop Type Required Notes
source string true The title of the parent node.
target string true The title of the child node.
type string false Edge type, for displaying a custom SVG shape.
handleText string false Text to render on the edge.
handleTooltipText string false Used to render the SVG title element.
label_from string false Text to render along the edge with label_to.
label_to string false Text to render along the edge with label_from.

Imperative API

You can call these methods on the GraphView class using a ref.

Method Type Notes
panToNode (id: string, zoom?: boolean) => void Center the node given by id within the viewport, optionally zoom in to fit it.
panToEdge (source: string, target: string, zoom?: boolean) => void Center the edge between source and target node IDs within the viewport, optionally zoom in to fit it.

Deprecation Notes

Prop Type Required Notes
emptyType string true 'Default' node type.
getViewNode func true Node getter.
renderEdge func false Called to render edge geometry.
enableFocus bool false Adds a 'focus' toggle state to GraphView.
transitionTime number false Fade-in/Fade-out time.
primary string false Primary color.
light string false Light color.
dark string false Dark color.
style object false Style prop for wrapper.
gridDot number false Grid dot size.
graphControls boolean true Whether to show zoom controls.