Nodejs 中使用 GoJS

As of 2.0, GoJS can be used in DOM-less contexts like Node.js. However there are some considerations:

• Since there is no Diagram DIV, you must instead set the Diagram.viewSize property. This affects all the same values as the DIV size, like Diagram.position and layout results from layouts that are viewport-sized.
• Cannot measure go.Pictures, you must set a GraphObject.desiredSize instead.
• Cannot measure go.TextBlocks accurately, you should set a GraphObject.desiredSize instead.

For server-side operations that need to measure Pictures or TextBlocks, you should consider using a headless browser with Node. Click here for examples using Node with Puppeteer (headless Chrome).

Node.js example

If you saved the following JavaScript as nodescript.js and run it with node (node nodescript.js), it will output Model JSON results in the console, which include the locations of laid-out Nodes. You can use Node.js in this way to do server-side operations like large layouts, and then send the JSON to the client.

// This example loads the GoJS library, creates a Diagram with a layout and prints the JSON results,

// Reference GoJS. This assumes its in the same directory as this script:
require('./go.js');

var $ = go.GraphObject.make;  // for conciseness in defining templates

myDiagram = $(go.Diagram, '', // No DIV
         {
            viewSize: new go.Size(400,400), // Set this property in DOM-less environments
            layout: $(go.LayeredDigraphLayout),
            'animationManager.isEnabled': false
         });

// define a simple Node template
myDiagram.nodeTemplate =
  $(go.Node, 'Auto',
    new go.Binding('location', 'loc', go.Point.Parse).makeTwoWay(go.Point.Stringify),
    $(go.Shape, 'RoundedRectangle', { strokeWidth: 0},
      // Shape.fill is bound to Node.data.color
      new go.Binding('fill', 'color')),
    $(go.TextBlock,
      { margin: 8 },  // some room around the text
      // TextBlock.text is bound to Node.data.key
      new go.Binding('text', 'key'))
  );

// After the layout, output results:
myDiagram.addDiagramListener('InitialLayoutCompleted', function() {
  console.log(myDiagram.model.toJSON());
});

// load a model:
myDiagram.model = new go.GraphLinksModel(
[
  { key: 'Alpha', color: 'lightblue' },
  { key: 'Beta', color: 'orange' },
  { key: 'Gamma', color: 'lightgreen' },
  { key: 'Delta', color: 'pink' }
],
[
  { from: 'Alpha', to: 'Beta' },
  { from: 'Alpha', to: 'Gamma' },
  { from: 'Beta', to: 'Beta' },
  { from: 'Gamma', to: 'Delta' },
  { from: 'Delta', to: 'Alpha' }
]);