dom-screenshot

A modern TypeScript library to capture DOM elements as SVG, PNG, JPEG, or Blob images. Built with latest tooling and fully type-safe.

Forked & modified from dom-to-image

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✨ Features

• 📸 Multiple Formats: SVG (vector), PNG (raster), JPEG (compressed), Blob, Pixel Data
• 🎨 Style Preservation: Captures all CSS styles, colors, gradients, shadows, transforms
• 📦 Modern Build: Rollup with TypeScript, ESM and CommonJS outputs
• 🔒 Type Safe: Full TypeScript support with complete type definitions
• ⚡ Fast: Optimized for performance, lazy initialization of dependencies
• 🚀 Production Ready: Tested and used in real-world applications
• 🎯 React Friendly: Works seamlessly with React via refs

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📚 Documentation

Quick Reference

• 🎬 Live Demo → Try it now! (no setup needed)
• Getting Started → See below or check EXAMPLES_QUICKSTART.md
• React Example → Run the interactive example in examples/react-app/
• Testing → See TESTING.md for test setup
• Examples → Check examples/README.md for detailed examples

File Guides

File	Purpose
EXAMPLES_QUICKSTART.md	Quick start guide for running examples
TESTING.md	Testing framework setup and usage
TESTING_STATUS.md	Current test status and results
TEST_SETUP_SUMMARY.md	Comprehensive testing documentation
examples/README.md	Examples overview
examples/react-app/README.md	Detailed React example guide
tests/README.md	Test infrastructure details

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🎬 Live Demo

Try it now! → dom-screenshot React Demo

Experience the library in action with an interactive React application. Capture UI elements as SVG, PNG, or JPEG with live preview! 🚀

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🚀 Quick Start

Installation

npm install @mkhuda/dom-screenshot
# or
yarn add @mkhuda/dom-screenshot

Basic Usage

import { domtoimage } from '@mkhuda/dom-screenshot';

// Get the element to capture
const element = document.getElementById('content');

// Capture as SVG
const svg = await domtoimage.toSvg(element);

// Capture as PNG
const png = await domtoimage.toPng(element);

// Capture as JPEG
const jpeg = await domtoimage.toJpeg(element);

// Get as Blob
const blob = await domtoimage.toBlob(element);

// Get pixel data
const pixelData = await domtoimage.toPixelData(element);

React Example

import { useRef } from 'react';
import { domtoimage } from '@mkhuda/dom-screenshot';

export function MyComponent() {
  const contentRef = useRef<HTMLDivElement>(null);

  const handleCapture = async () => {
    if (!contentRef.current) return;

    try {
      const png = await domtoimage.toPng(contentRef.current);

      // Download
      const link = document.createElement('a');
      link.href = png;
      link.download = 'screenshot.png';
      link.click();
    } catch (error) {
      console.error('Capture failed:', error);
    }
  };

  return (
    <div>
      <div ref={contentRef}>
        <h1>Content to capture</h1>
        <p>This will be captured</p>
      </div>
      <button onClick={handleCapture}>📸 Download as PNG</button>
    </div>
  );
}

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📸 API Reference

Functions

toSvg(node, options?)

Renders DOM node to SVG data URL (scalable vector format).

Returns: Promise<string> - SVG data URL

Best for: UI components, diagrams, simple graphics

const svg = await domtoimage.toSvg(element);

toPng(node, options?)

Renders DOM node to PNG data URL (lossless raster format).

Returns: Promise<string> - PNG data URL

Best for: Screenshots, general purpose captures

const png = await domtoimage.toPng(element);

toJpeg(node, options?)

Renders DOM node to JPEG data URL (lossy compressed format).

Returns: Promise<string> - JPEG data URL

Best for: Photos, space-constrained scenarios

const jpeg = await domtoimage.toJpeg(element, { quality: 0.95 });

toBlob(node, options?)

Renders DOM node to Blob object.

Returns: Promise<Blob> - Blob object

Best for: Uploading to server, efficient data handling

const blob = await domtoimage.toBlob(element);

toPixelData(node, options?)

Extracts raw pixel data from DOM node.

Returns: Promise<Uint8ClampedArray> - RGBA pixel data

Best for: Image processing, pixel manipulation

const pixelData = await domtoimage.toPixelData(element);

Options

interface DomScreenshotOptions {
  width?: number;           // Override width
  height?: number;          // Override height
  bgcolor?: string;         // Background color
  quality?: number;         // JPEG quality (0-1)
  style?: CSSStyleDeclaration;  // Additional styles
  filter?: (node: Node) => boolean;  // Filter nodes
  cacheBust?: boolean;      // Bust cache with random query
  imagePlaceholder?: string; // Placeholder for broken images
}

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🎯 Real-World Use Cases

1. Export Feature

Let users download rendered UI as images:

const png = await domtoimage.toPng(contentElement);
downloadFile(png, 'export.png');

2. Report Generation

Create visual reports from data:

const reports = await Promise.all([
  domtoimage.toPng(chart1),
  domtoimage.toPng(chart2),
  domtoimage.toPng(table),
]);

3. Screenshot Tools

Build screenshot applications:

const screenshots = [];
screenshots.push(await domtoimage.toPng(screen1));
screenshots.push(await domtoimage.toPng(screen2));

4. Documentation

Auto-capture UI for documentation:

const componentScreenshot = await domtoimage.toSvg(component);

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🧪 Testing

The project includes a comprehensive test suite with:

• ✅ 20 infrastructure tests
• ✅ Unit tests for all functions
• ✅ Integration tests
• ✅ Custom test matchers
• ✅ Full TypeScript support

Run Tests

# Run tests once
npm run test:run

# Watch mode
npm run test:watch

# UI dashboard
npm run test:ui

# Coverage report
npm run test:coverage

See TESTING.md for detailed testing information.

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💻 Examples

🎬 Live Demo

Experience the library instantly without any setup:

• dom-screenshot React Demo - Interactive demo with live preview
• Supports SVG, PNG, JPEG capture
• Real-time gallery view
• Auto-download functionality

React Example App

A complete, production-ready React application demonstrating all features:

Features:

• Capture as SVG, PNG, JPEG
• Live preview gallery
• Auto-download files
• Beautiful responsive UI
• Full TypeScript

Quick Start:

npm run example:dev

Opens at http://localhost:5173

For detailed information, see:

• EXAMPLES_QUICKSTART.md - Quick reference
• examples/README.md - Examples overview
• examples/react-app/README.md - Detailed guide

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🏗️ Project Structure

dom-screenshot/
├── src/
│   ├── dom-screenshot.ts         # Main library
│   └── types/
│       └── options.ts             # Type definitions
├── dist/
│   ├── dom-screenshot.esm.js      # ES Module
│   ├── dom-screenshot.min.js      # IIFE (minified)
│   └── dom-screenshot.d.ts        # TypeScript types
├── tests/
│   ├── setup.ts                   # Test configuration
│   ├── helpers/                   # Test utilities
│   ├── mocks/                     # Mock implementations
│   ├── fixtures/                  # Test data
│   └── unit/
│       ├── simple.test.ts         # Infrastructure tests
│       └── basic.test.ts          # Feature tests
├── examples/
│   └── react-app/                 # React example application
├── vitest.config.mts              # Test runner config
├── tsconfig.json                  # TypeScript config
├── rollup.config.mjs              # Build config
└── package.json

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🛠️ Development

Prerequisites

• Node.js 22.12.0 (pinned with Volta)
• npm or yarn

Setup

# Install dependencies
npm install

# Build library
npm run build

# Watch for changes
npm run watch

Build Commands

npm run build              # Build production
npm run test:run           # Run tests
npm run test:watch         # Watch tests
npm run test:ui            # Test UI dashboard
npm run example:dev        # Run React example
npm run example:build      # Build React example

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📊 What's New (TypeScript Migration)

✅ Completed

• ✅ Full TypeScript migration
• ✅ Strict type checking enabled
• ✅ Modern build tooling (Rollup 4.x, TypeScript 5.x)
• ✅ ESM and CommonJS dual output
• ✅ Complete test suite (20+ tests passing)
• ✅ Production-ready React example
• ✅ Comprehensive documentation

🎯 Quality Metrics

Metric	Status
TypeScript	✅ Full coverage with strict mode
Tests	✅ 20+ tests passing
Build	✅ 0 errors
Output	✅ ESM + IIFE dual format
Types	✅ Complete definitions
Docs	✅ Comprehensive guides

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🚀 Browser Support

• ✅ Chrome/Chromium (latest)
• ✅ Firefox (latest)
• ✅ Safari (latest)
• ✅ Edge (latest)

For older browsers, ensure required polyfills are present.

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🔄 Format Comparison

Format	Use Case	Size	Speed	Quality
SVG	UI/Diagrams	Smallest	Fastest	Vector
PNG	General Purpose	Medium	Medium	Lossless
JPEG	Photos	Smallest	Slower	Lossy
Blob	Server Upload	Any	Any	Any

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⚙️ Advanced Options

Custom Dimensions

const png = await domtoimage.toPng(element, {
  width: 1920,
  height: 1080,
});

Background Color

const png = await domtoimage.toPng(element, {
  bgcolor: '#ffffff',
});

JPEG Quality

const jpeg = await domtoimage.toJpeg(element, {
  quality: 0.95,  // 0 to 1
});

Filter Nodes

const svg = await domtoimage.toSvg(element, {
  filter: (node) => {
    // Exclude elements with class 'no-capture'
    if (node instanceof HTMLElement) {
      return !node.classList.contains('no-capture');
    }
    return true;
  },
});

Cache Busting

const png = await domtoimage.toPng(element, {
  cacheBust: true,  // Add random query string to URLs
});

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🐛 Troubleshooting

Styles Not Captured

• Ensure styles are inline or in <style> tags
• External stylesheets may not be included
• Use computed styles for debugging

Canvas-Related Errors

• SVG capture works in all environments
• PNG/JPEG may need browser environment
• Always use try-catch blocks

Performance Issues

• Use SVG for simple UI elements
• Break large captures into sections
• Cache element references

Import Errors

• Ensure library is built: npm run build
• Check Node.js version: node --version
• Try reinstalling: rm -rf node_modules && npm install

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📄 File Guides

Main Documentation Files

TESTING.md

Quick reference for:

• Running tests
• Test commands
• Test patterns

TESTING_STATUS.md

Current test status:

• Test results
• Coverage information
• Known issues

TEST_SETUP_SUMMARY.md

Comprehensive testing:

• Setup details
• Infrastructure overview
• Test organization

EXAMPLES_QUICKSTART.md

Quick start for examples:

• Installation steps
• Running instructions
• Troubleshooting

examples/README.md

Examples overview:

• Available examples
• Features demonstrated
• Technologies used

examples/react-app/README.md

React example details:

• Project structure
• Component documentation
• Customization guide

tests/README.md

Testing infrastructure:

• Test setup
• Helper utilities
• Mock implementations

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🤝 Contributing

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Add tests for new features
4. Ensure all tests pass
5. Submit a pull request

See TESTING.md for test setup instructions.

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📝 License

MIT

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🙏 Acknowledgments

• Original library: dom-to-image by tsayen
• Modern tooling and TypeScript migration by Muhammad K. Huda

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📞 Support

• 📖 Check the documentation files listed above
• 🐛 Found a bug? Open an issue
• 💬 Have questions? Check existing issues or discussions
• 🚀 Want to contribute? See Contributing section

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Ready to capture?

• 🎬 Try the Live Demo instantly
• 📖 Read the Quick Start
• 💻 Check the React Example

Let's start capturing! 📸