Source: editor/extensions/ext-server_moinsave.js

/**
 * @file ext-server_moinsave.js
 *
 * @license (MIT OR GPL-2.0-or-later)
 *
 * @copyright 2010 Alexis Deveria, 2011 MoinMoin:ReimarBauer
 *  adopted for moinmoins item storage. It sends in one post png and svg data
 *  (I agree to dual license my work to additional GPLv2 or later)
 */
import {canvg} from '../canvg/canvg.js';

export default {
  name: 'server_moinsave',
  async init ({$, encode64, importLocale}) {
    const strings = await importLocale();
    const svgEditor = this;
    const svgCanvas = svgEditor.canvas;
    const saveSvgAction = '/+modify';

    // Create upload target (hidden iframe)
    //  Hiding by size instead of display to avoid FF console errors
    //    with `getBBox` in browser.js `supportsPathBBox_`)
    /* const target = */ $(
      `<iframe name="output_frame" title="${strings.hiddenframe}"
        style="width: 0; height: 0;" src="data:text/html;base64,PGh0bWw+PC9odG1sPg=="/>`
    ).appendTo('body');

    svgEditor.setCustomHandlers({
      async save (win, data) {
        const svg = '<?xml version="1.0"?>\n' + data;
        const {pathname} = new URL(location);
        const name = pathname.replace(/\/+get\//, '');
        const svgData = encode64(svg);
        if (!$('#export_canvas').length) {
          $('<canvas>', {id: 'export_canvas'}).hide().appendTo('body');
        }
        const c = $('#export_canvas')[0];
        c.width = svgCanvas.contentW;
        c.height = svgCanvas.contentH;
        await canvg(c, svg);
        const datauri = c.toDataURL('image/png');
        // const {uiStrings} = svgEditor;
        const pngData = encode64(datauri); // Brett: This encoding seems unnecessary
        /* const form = */ $('<form>').attr({
          method: 'post',
          action: saveSvgAction + '/' + name,
          target: 'output_frame'
        }).append(`
          <input type="hidden" name="png_data" value="${pngData}">
          <input type="hidden" name="filepath" value="${svgData}">
          <input type="hidden" name="filename" value="drawing.svg">
          <input type="hidden" name="contenttype" value="application/x-svgdraw">
        `).appendTo('body')
          .submit().remove();
        $.alert(strings.saved);
        top.window.location = '/' + name;
      }
    });
  }
};