Subversion Repositories oidplus

<?php

/*

 * OIDplus 2.0

 * Copyright 2019 Daniel Marschall, ViaThinkSoft

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

// We do this stuff to avoid that the client includes an external JavaScript from polyfill.io,

// since some users might have a problem with that (in regards privacy of their IP address etc.)

// So, the OIDplus webserver will act as proxy.

define('REQUIRED_POLYFILLS', array(

        // Internet Explorer for various AJAX calls

        'fetch',

        'URL',

        // Internet Explorer for TinyMCE if it is included inside oidplus.min.js.php ( https://github.com/tinymce/tinymce/blob/5c1702a119e683f93e03ecc2231f11d17ce57395/modules/tinymce/src/core/main/ts/api/EditorManager.ts#L271 )

        'document.currentScript'

));

define('MINIFY_POLYFILL', true); // TODO: put into baseconfig?

define('POLYFILL_CACHE_MAX_AGE', 24*60*60); // 1 day, TODO: put into baseconfig?

# ---

require_once __DIR__ . '/includes/functions.inc.php';

if (!isset($_SERVER['HTTP_USER_AGENT'])) {

        $out = '/* ERROR: No User Agent available */';

        httpOutWithETag($out, 'application/javascript', 'polyfill'.(MINIFY_POLYFILL ? '.min' : '').'.js');

}

$ua = $_SERVER['HTTP_USER_AGENT'];

if (MINIFY_POLYFILL) {

        $cache_file = __DIR__ . '/userdata/cache/.polyfill_'.md5(implode(',',REQUIRED_POLYFILLS)).'_'.md5($ua).'.min.js';

} else {

        $cache_file = __DIR__ . '/userdata/cache/.polyfill_'.md5(implode(',',REQUIRED_POLYFILLS)).'_'.md5($ua).'.js';

}

if (!file_exists($cache_file) || (time()-filemtime($cache_file)) > POLYFILL_CACHE_MAX_AGE) {

        if (MINIFY_POLYFILL) {

                $url = 'https://polyfill.io/v3/polyfill.min.js?features='.urlencode(implode(',',REQUIRED_POLYFILLS));

        } else {

                $url = 'https://polyfill.io/v3/polyfill.js?features='.urlencode(implode(',',REQUIRED_POLYFILLS));

        }

        $opts = [

            "http" => [

                "method" => "GET",

                "header" => "User-Agent: ".$ua."\r\n"

            ]

        ];

        $context = stream_context_create($opts);

        $cont = @file_get_contents($url, false, $context);

        if ($cont === false) {

                if (file_exists($cache_file)) {

                        $out = file_get_contents($cache_file);

                        // In case polyfill.io is down, don't delay further requests

                        // Instead, try again after the next max cache age

                        touch($cache_file);

                } else {

                        $out = '/* ERROR: polyfill.io not available and no cache file exists! */';

                        httpOutWithETag($out, 'application/javascript', 'polyfill'.(MINIFY_POLYFILL ? '.min' : '').'.js');

                }

        } else {

                $ua = str_replace('*/', '', $ua);

                $cont = '/* Polyfill '.$url.' for '.$ua.' */'.$cont;

                if (POLYFILL_CACHE_MAX_AGE > 0) {

                        @file_put_contents($cache_file, $cont);

                }

                $out = $cont;

        }

} else {

        $out = file_get_contents($cache_file);

}

# ---

httpOutWithETag($out, 'application/javascript', 'polyfill'.(MINIFY_POLYFILL ? '.min' : '').'.js');