gojs

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sidebar-nav flex-grow px-1 lg:px-4 pb-4 md:pb-0 md:overflow-y-auto break-words"> <a href="index.html">Basics</a> <a href="buildingObjects.html">Building Parts</a> <a href="usingModels.html">Using Models</a> <a href="dataBinding.html">Data Binding</a> <a href="react.html">GoJS with React</a> <a href="angular.html">GoJS with Angular</a> <a href="textBlocks.html">TextBlocks</a> <a href="shapes.html">Shapes</a> <a href="pictures.html">Pictures</a> <a href="panels.html">Panels</a> <a href="tablePanels.html">Table Panels</a> <a href="brush.html">Brushes</a> <a href="sizing.html">Sizing Objects</a> <a href="itemArrays.html">Item Arrays</a> <a href="changedEvents.html">Changed Events</a> <a href="transactions.html">Transactions</a> <a href="viewport.html">Coordinates</a> <a href="initialView.html">Initial View</a> <a href="collections.html">Collections</a> <a href="links.html">Links</a> <a href="linkLabels.html">Link Labels</a> <a href="connectionPoints.html">Link Points</a> <a 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create images of Diagrams with <b>GoJS</b>, and this page details some of the options for such a task. </p> <h2 id="Puppeteer">Puppeteer</h2> <p> <a href="https://github.com/GoogleChrome/puppeteer">Puppeteer</a> is a Node library which provides a high-level API to control headless Chrome. We can use it to create images server-side. If you have Node and npm installed you can install it with <code>npm install puppeteer</code>. <p> The following code is a small example using Puppeteer. If you saved the JavaScript as <code>puppet.js</code> and run it with node (<code>node createImage.js</code>) it demonstrate creating two images: One from the Diagram called <code>gojs-screenshot.png</code> and one of the HTML page called <code>page-screenshot.png</code>. The Diagram code in the sample is the same as that in the <a href="../samples/minimal.html">Minimal sample</a>. </p> <pre class="lang-js"><code> // This example loads the GoJS library then adds HTML from scratch and evaluates some JavaScript, // then creates a screenshot of Diagram with makeImageData, plus a screenshot of the page. const puppeteer = require('puppeteer'); const fs = require('fs'); const parseDataUrl = (dataUrl) => { const matches = dataUrl.match(/^data:(.+);base64,(.+)$/); if (matches.length !== 3) { throw new Error('Could not parse data URL.'); } return { mime: matches[1], buffer: Buffer.from(matches[2], 'base64') }; }; (async () => { const browser = await puppeteer.launch(); const page = await browser.newPage(); // Point to a version of go.js, either a local file or one on the web at a CDN await page.addScriptTag({ url: 'https://unpkg.com/gojs' // path: '../../release/go.js' }); // Create HTML for the page: page.setContent('<div id="myDiagramDiv" style="border: solid 1px black; width:400px; height:400px"></div>'); // Set up a Diagram, and return the result of makeImageData: const imageData = await page.evaluate(() => { var $ = go.GraphObject.make; var myDiagram = new go.Diagram("myDiagramDiv", { "animationManager.isEnabled": false, "undoManager.isEnabled": true // enable undo & redo }); // define a simple Node template myDiagram.nodeTemplate = $(go.Node, "Auto", // the Shape will go around the TextBlock $(go.Shape, "RoundedRectangle", { strokeWidth: 0 }, new go.Binding("fill", "color")), $(go.TextBlock, { margin: 8 }, new go.Binding("text", "key")) ); myDiagram.model = new go.GraphLinksModel( [ { key: "Alpha", color: "lightblue" }, { key: "Beta", color: "orange" }, { key: "Gamma", color: "lightgreen" }, { key: "Delta", color: "pink" } ], [ { from: "Alpha", to: "Beta" }, { from: "Alpha", to: "Gamma" }, { from: "Beta", to: "Beta" }, { from: "Gamma", to: "Delta" }, { from: "Delta", to: "Alpha" } ]); return myDiagram.makeImageData(); }); // Output the GoJS makeImageData as a .png: const { buffer } = parseDataUrl(imageData); fs.writeFileSync('diagram-screenshot.png', buffer, 'base64'); // Output a page screenshot await page.screenshot({ path: 'page-screenshot.png' }); await browser.close(); })(); </code></pre> <p> You can also use Puppeteer to fetch live HTML pages and do the same operations: </p> <pre class="lang-js"><code> // This example loads a web page with a GoJS diagram, // then creates a screenshot of the Diagram with makeImageData, plus a screenshot of the page. const puppeteer = require('puppeteer'); const fs = require('fs'); const parseDataUrl = (dataUrl) => { const matches = dataUrl.match(/^data:(.+);base64,(.+)$/); if (matches.length !== 3) { throw new Error('Could not parse data URL.'); } return { mime: matches[1], buffer: Buffer.from(matches[2], 'base64') }; }; (async () => { const browser = await puppeteer.launch(); const page = await browser.newPage(); // This does not have to be a page on the web, it can be a localhost page, or file:// await page.goto('https://gojs.net/samples/orgChartEditor.html', { waitUntil: 'networkidle2' // ensures images are loaded }); const imageData = await page.evaluate(() => { window.myDiagram.animationManager.stopAnimation(); return window.myDiagram.makeImageData({ background: window.myDiagram.div.style.backgroundColor }); }); // Output the GoJS makeImageData as a .png: const { buffer } = parseDataUrl(imageData); fs.writeFileSync('diagram-screenshot.png', buffer, 'base64'); // Output a page screenshot await page.screenshot({ path: 'page-screenshot.png' }); await browser.close(); })(); </code></pre> </div> </div> <div class="bg-nwoods-primary"> <section class="max-w-screen-lg text-white container mx-auto py-2 px-12"> <p id="version" class="leading-none mb-2 my-4">GoJS</p> </section> </div><footer class="bg-nwoods-primary text-white"> <div class="container max-w-screen-lg mx-auto px-8"> <div class="w-full py-6"> <div class="max-w-screen-lg xl:max-w-screen-xl mx-auto px-4 sm:px-6 md:px-8"> <ul class="text-sm font-medium pb-6 grid grid-cols-2 sm:grid-cols-3 gap-y-10"> <li class="list-none row-span-2"> <h2 class="text-base font-semibold tracking-wide">GoJS</h2> <ul class="list-none space-y-4 md:space-y-1 px-0"> <li> <a href="../samples/index.html">Samples</a> </li> <li> <a href="../learn/index.html">Learn</a> </li> <li> <a href="../intro/index.html">Intro</a> </li> <li> <a href="../api/index.html">API</a> </li> <li> <a href="../changelog.html">Changelog</a> </li> <li> <a href="https://github.com/NorthwoodsSoftware/GoJS">GitHub</a> </li> </ul> </li> <li class="list-none row-span-2"> <h2 class="text-base font-semibold tracking-wide">Support</h2> <ul class="list-none space-y-4 md:space-y-1 px-0"> <li> <a href="https://www.nwoods.com/contact.html" target="_blank" rel="noopener" onclick="getOutboundLink('https://www.nwoods.com/contact.html', 'contact');">Contact</a> </li> <li> <a href="https://forum.nwoods.com/c/gojs">Forum</a> </li> <li> <a href="https://www.nwoods.com/app/activate.aspx?sku=gojs">Activate</a> </li> <li> <a href="https://www.nwoods.com/sales/index.html" target="_blank" rel="noopener" onclick="getOutboundLink('https://www.nwoods.com/sales/index.html', 'buy');">Buy</a> </li> <li> <a href="https://www.youtube.com/channel/UC9We8EoX596-6XFjJDtZIDg">Videos</a> </li> </ul> </li> <li class="list-none row-span-2"> <h2 class="text-base font-semibold tracking-wide">Company</h2> <ul class="list-none space-y-4 md:space-y-1 px-0"> <li> <a target="_blank" href="https://www.nwoods.com">Northwoods</a> </li> <li> <a target="_blank" href="https://www.nwoods.com/about.html">About Us</a> </li> <li> <a target="_blank" href="https://www.nwoods.com/contact.html">Contact Us</a> </li> <li> <a target="_blank" href="https://www.nwoods.com/consulting.html">Consulting</a> </li> <li> <a target="_blank" href="https://twitter.com/northwoodsgo">Twitter</a> </li> </ul> </li> </ul> <p class="text-sm text-gray-100 md:mb-6"> Copyright 1998-2023 <a class="text-white" href="https://www.nwoods.com">Northwoods Software</a> </p> </div> </div> </footer> </body> <script async src="https://www.googletagmanager.com/gtag/js?id=G-S5QK8VSK84"></script> <script> window.dataLayer = window.dataLayer || []; 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