wikimedia/mediawiki-core

<?php
/**
 * The web entry point for generating an OpenSearch description document.
 *
 * See <http://www.opensearch.org/> for the specification of the OpenSearch
 * "description" document. In a nut shell, this tells browsers how and where
 * to submit submit search queries to get a search results page back,
 * as well as how to get typeahead suggestions (see ApiOpenSearch).
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup entrypoint
 */

use MediaWiki\HookContainer\HookRunner;
use MediaWiki\MediaWikiServices;
use MediaWiki\SpecialPage\SpecialPage;

// This endpoint is supposed to be independent of request cookies and other
// details of the session. Enforce this constraint with respect to session use.
define( 'MW_NO_SESSION', 1 );

define( 'MW_ENTRY_POINT', 'opensearch_desc' );

require_once __DIR__ . '/includes/WebStart.php';

wfOpenSearchDescMain();

function wfOpenSearchDescMain() {
    global $wgRequest, $wgFavicon, $wgOpenSearchTemplates;

    if ( $wgRequest->getVal( 'ctype' ) == 'application/xml' ) {
        // Makes testing tweaks about a billion times easier
        $ctype = 'application/xml';
    } else {
        $ctype = 'application/opensearchdescription+xml';
    }

    $response = $wgRequest->response();
    $response->header( "Content-type: $ctype" );

    // Set an Expires header so that CDN can cache it for a short time
    // Short enough so that the sysadmin barely notices when $wgSitename is changed
    $expiryTime = 600; # 10 minutes
    $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', time() + $expiryTime ) . ' GMT' );
    $response->header( 'Cache-control: max-age=600' );

    print '<?xml version="1.0"?>';
    print Xml::openElement( 'OpenSearchDescription',
        [
            'xmlns' => 'http://a9.com/-/spec/opensearch/1.1/',
            'xmlns:moz' => 'http://www.mozilla.org/2006/browser/search/' ] );

    // The spec says the ShortName must be no longer than 16 characters,
    // but 16 is *realllly* short. In practice, browsers don't appear to care
    // when we give them a longer string, so we're no longer attempting to trim.
    //
    // Note: ShortName and the <link title=""> need to match; they are used as
    // a key for identifying if the search engine has been added already, *and*
    // as the display name presented to the end-user.
    //
    // Behavior seems about the same between Firefox and IE 7/8 here.
    // 'Description' doesn't appear to be used by either.
    $fullName = wfMessage( 'opensearch-desc' )->inContentLanguage()->text();
    print Xml::element( 'ShortName', null, $fullName );
    print Xml::element( 'Description', null, $fullName );

    $services = MediaWikiServices::getInstance();

    // By default we'll use the site favicon.
    // Double-check if IE supports this properly?
    print Xml::element( 'Image',
        [
            'height' => 16,
            'width' => 16,
            'type' => 'image/x-icon'
        ],
        (string)$services->getUrlUtils()->expand( $wgFavicon, PROTO_CURRENT )
    );

    $urls = [];

    // General search template. Given an input term, this should bring up
    // search results or a specific found page.
    // At least Firefox and IE 7 support this.
    $searchPage = SpecialPage::getTitleFor( 'Search' );
    $urls[] = [
        'type' => 'text/html',
        'method' => 'get',
        'template' => $searchPage->getCanonicalURL( 'search={searchTerms}' ) ];

    foreach ( $wgOpenSearchTemplates as $type => $template ) {
        if ( !$template ) {
            $template = ApiOpenSearch::getOpenSearchTemplate( $type );
        }

        if ( $template ) {
            $urls[] = [
                'type' => $type,
                'method' => 'get',
                'template' => $template,
            ];
        }
    }

    // Allow hooks to override the suggestion URL settings in a more
    // general way than overriding the whole search engine...
    ( new HookRunner( $services->getHookContainer() ) )->onOpenSearchUrls( $urls );

    foreach ( $urls as $attribs ) {
        print Xml::element( 'Url', $attribs );
    }

    // And for good measure, add a link to the straight search form.
    // This is a custom format extension for Firefox, which otherwise
    // sends you to the domain root if you hit "enter" with an empty
    // search box.
    print Xml::element( 'moz:SearchForm', null,
        $searchPage->getCanonicalURL() );

    print '</OpenSearchDescription>';
}