electron/lib/renderer/api/desktop-capturer.ts

import { nativeImage } from 'electron';
import { ipcRendererInternal } from '@electron/internal/renderer/ipc-renderer-internal';

const { hasSwitch } = process.electronBinding('command_line');

// |options.types| can't be empty and must be an array
function isValid (options: Electron.SourcesOptions) {
  const types = options ? options.types : undefined;
  return Array.isArray(types);
}

const enableStacks = hasSwitch('enable-api-filtering-logging');

function getCurrentStack () {
  const target = {};
  if (enableStacks) {
    Error.captureStackTrace(target, getCurrentStack);
  }
  return (target as any).stack;
}

export async function getSources (options: Electron.SourcesOptions) {
  if (!isValid(options)) throw new Error('Invalid options');

  const captureWindow = options.types.includes('window');
  const captureScreen = options.types.includes('screen');

  const { thumbnailSize = { width: 150, height: 150 } } = options;
  const { fetchWindowIcons = false } = options;

  const sources = await ipcRendererInternal.invoke<ElectronInternal.GetSourcesResult[]>('ELECTRON_BROWSER_DESKTOP_CAPTURER_GET_SOURCES', {
    captureWindow,
    captureScreen,
    thumbnailSize,
    fetchWindowIcons
  } as ElectronInternal.GetSourcesOptions, getCurrentStack());

  return sources.map(source => ({
    id: source.id,
    name: source.name,
    thumbnail: nativeImage.createFromDataURL(source.thumbnail),
    display_id: source.display_id,
    appIcon: source.appIcon ? nativeImage.createFromDataURL(source.appIcon) : null
  }));
}