web/docs.dart

// Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:html';

import 'highlight.dart' as highlight;
import 'search.dart' as search;
import 'sidenav.dart' as sidenav;
import 'theme.dart' as theme;

void main() {
  highlight.init();
  initializeSidebars();
  sidenav.init();
  search.init();
  theme.init();
}

void initializeSidebars() {
  final body = document.querySelector('body');
  if (body == null) {
    return;
  }
  final dataUsingBaseHref = body.dataset['using-base-href'];
  if (dataUsingBaseHref == null) {
    // This should never happen.
    return;
  }
  var baseHref = '';
  if (dataUsingBaseHref != 'true') {
    final dataBaseHref = body.dataset['base-href'];
    if (dataBaseHref == null) {
      return;
    }
    baseHref = dataBaseHref;
  }
  final mainContent = document.querySelector('#dartdoc-main-content');
  if (mainContent == null) {
    return;
  }
  final aboveSidebarPath = mainContent.dataset['above-sidebar'];
  final leftSidebar = document.querySelector('#dartdoc-sidebar-left-content');
  final sanitizer = _SidebarNodeTreeSanitizer(baseHref);
  if (aboveSidebarPath != null &&
      aboveSidebarPath.isNotEmpty &&
      leftSidebar != null) {
    HttpRequest.getString('$baseHref$aboveSidebarPath').then((content) {
      leftSidebar.setInnerHtml(content, treeSanitizer: sanitizer);
    });
  }
  final belowSidebarPath = mainContent.dataset['below-sidebar'];
  final rightSidebar = document.querySelector('#dartdoc-sidebar-right');
  if (belowSidebarPath != null &&
      belowSidebarPath.isNotEmpty &&
      rightSidebar != null) {
    HttpRequest.getString('$baseHref$belowSidebarPath').then((content) {
      rightSidebar.setInnerHtml(content, treeSanitizer: sanitizer);
    });
  }
}

/// A permissive sanitizer that allows external links (e.g. to api.dart.dev) and
/// adjusts the links in a newly loaded sidebar, if "base href" is not being
/// used.
class _SidebarNodeTreeSanitizer implements NodeTreeSanitizer {
  final String baseHref;

  _SidebarNodeTreeSanitizer(this.baseHref);

  @override
  void sanitizeTree(Node node) {
    if (node is Element && node.nodeName == 'A') {
      final hrefString = node.attributes['href'];
      if (hrefString != null) {
        final href = Uri.parse(hrefString);
        if (!href.isAbsolute) {
          node.setAttribute('href', '$baseHref$hrefString');
        }
      }
    }
    node.childNodes.forEach(sanitizeTree);
  }
}