redirect.admin.class.php

<?php
require_once 'redirect.class.php';
/**
 * ----------------------------------------------------------------------
 *   _____ __  __ _        _____          _ _               _   
 *  |_   _|  \/  | |      |  __ \        | (_)             | |  
 *    | | | \  / | |      | |__) |___  __| |_ _ __ ___  ___| |_ 
 *    | | | |\/| | |      |  _  // _ \/ _` | | '__/ _ \/ __| __|
 *   _| |_| |  | | |____  | | \ \  __/ (_| | | | |  __/ (__| |_ 
 *  |_____|_|  |_|______| |_|  \_\___|\__,_|_|_|  \___|\___|\__|
 *
 * ----------------------------------------------------------------------
 * Loads a config json from outside webroot and makes a 3xx redirect
 * if the definition exists
 * ----------------------------------------------------------------------
 * 2020-05-11  v1.4  ah  rewrite as class
 * 2022-02-03  v1.5  ah  add method isEnabled
 * 2022-05-23  v1.6  ah  add http head check+render output; 
 * 2022-05-31  v1.7  ah  optical changes
 */

/**
 * Description of redirect
 *
 * @author axel
 */
class redirectadmin extends redirect {

    protected function _getCurlOptions(){
        $aReturn=array(
            CURLOPT_HEADER => true,
            CURLOPT_FOLLOWLOCATION => true,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_USERAGENT => strip_tags($this->sAbout),
            CURLOPT_VERBOSE => false,
            CURLOPT_ENCODING => 'gzip, deflate',  // to fetch encoding
            CURLOPT_HTTPHEADER => array(
                'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8',
                'Accept-Language: en',
                'DNT: 1',
            ),

            // TODO: this is unsafe .. better: let the user configure it
            CURLOPT_SSL_VERIFYHOST => false,
            CURLOPT_SSL_VERIFYPEER => false,
            CURLOPT_TIMEOUT => 5,
        );
        return $aReturn;
    }

    /**
     * make a single http(s) get request and return the response body
     * @param string   $url          url to fetch
     * @param boolean  $bHeaderOnly  optional: true=make HEAD request; default: false (=GET)
     * @return string
     */
    public function httpGet($url, $bHeaderOnly = false) {
        $ch = curl_init($url);
        foreach ($this->_getCurlOptions() as $sCurlOption=>$sCurlValue){
            curl_setopt($ch, $sCurlOption, $sCurlValue);
        }
        if ($bHeaderOnly) {
            curl_setopt($ch, CURLOPT_HEADER, 1);
            curl_setopt($ch, CURLOPT_NOBODY, 1);
        }
        $res = curl_exec($ch);
        curl_close($ch);
        return ($res);
    }

    public function renderHttpResponseHeader($sHeader){
        $sReturn=$sHeader;
        if(!$sReturn){
            $sReturn='<pre><span class="status status-error">Request failed. </span><br>'
                .'No data... no response.<br>'
                .'Maybe ... '
                .'<ul>'
                    .'<li>the nostname does not exist ... </li>'
                    .'<li>or there is a network problem ... or </li>'
                    .'<li>the webservice on the target system does not run.</li>'
                .'</ul>'
            .'</pre>'
            ;
        } else {

            $sReturn=preg_replace('/(HTTP.*)\\r/', '</pre><pre><strong>$1</strong>', $sReturn);
            $sReturn=preg_replace('/(HTTP.*200.*)/', '<span class="status status-ok">$1</span>', $sReturn);
            $sReturn=preg_replace('/(HTTP.*30.*)/', '<span class="status status-redirect">$1</span>', $sReturn);
            $sReturn=preg_replace('/(HTTP.*40.*)/', '<span class="status status-error">$1</span>', $sReturn);
            $sReturn=preg_replace('/(HTTP.*50.*)/', '<span class="status status-error">$1</span>', $sReturn);
            $sReturn=preg_replace('/\ ([1-5][0-9][0-9])\ /', ' <span class="statuscode">$1</span> ', $sReturn);

            $sReturn=preg_replace('/(x-debug-.*)\\r/i', '<span class="debug">$1</span>', $sReturn);
            $sReturn=preg_replace('/(location:.*)\\r/i', '<span class="location">$1</span>', $sReturn);
            $sReturn.='</pre>';

            preg_match_all('/(HTTP\/.*)/i', $sReturn, $aTmp);
            // $sReturn.=print_r($aTmp, 1);
            $iHops=(count($aTmp[0])-1);

            $sReturn=($iHops>0
                ? 'Found hops: <strong>'.$iHops.'</strong>'
                    .($iHops>1 ? ' <span class="warning"> ⚠️ Verify your redirect to skip unneeded hops.</span>' : '' ).'<br><br>'
                : ''
                ).$sReturn
                ;
        }

        return $sReturn;
    }

    /**
     * check if admin is enabled
     * @return bool
     */
    public function isEnabled(){
        $sFile2Enable=__DIR__ . '/'.basename(__FILE__).'_enabled.txt';
        return file_exists($sFile2Enable);
    }

    /**
     * get ip address of a given hostname as ip (string) or false
     * @return string|bool
     */
    protected function _getIp($sHostname){
        $sIp=gethostbyname($sHostname);
        return $sIp===$sHostname ? false : $sIp;
    }

    /**
     * get an array with all config entries in all json files
     * including some error checking
     * @return array
     */
    public function getHosts(){
        $aReturn = array();
        $aErrors = array();
        foreach(glob($this->sConfigDir . '/redirects_*.json') as $sFilename){
            $sMyHost= str_replace(array('redirects_', '.json'), array('',''), basename($sFilename));
            $aReturn[$sMyHost]=array(
                'type'=>'config',
                'file'=>$sFilename,
                'ip'=> $this->_getIp($sMyHost),
                'aliases'=>array(),
                'redirects'=>json_decode(file_get_contents($sFilename), 1),
            );
            if (!$aReturn[$sMyHost]['ip']){
                $aErrors[]=basename($sFilename).': The hostname was not found in DNS: '.$sMyHost;
            }
        }
        $aAliases=$this->_getAliases();
        foreach($aAliases as $sAlias=>$sConfig){
            if(isset($aReturn[$sAlias])){
                $aErrors[]="alias.json: A configuration for alias [$sAlias] is useless. There exists a file redirects_{$sAlias}.json (which has priority).";
            } else {
                if(!isset($aReturn[$sConfig])){
                    $aErrors[]="alias.json: [$sAlias] points to a non existing host [$sConfig] - a file redirects_$sConfig.yml does not exist.";
                } else {
                    $aReturn[$sConfig]['aliases'][]=$sAlias;
                    $aReturn[$sAlias]=array(
                        'type'=>'alias',
                        'target'=>$sConfig,
                        'ip'=> $this->_getIp($sAlias),
                    );
                    if (!$aReturn[$sAlias]['ip']){
                        $aErrors[]='alias.json: The hostname was not found in DNS: '.$sAlias;
                    }
                }
            }
        }
        $aReturn['_errors']=$aErrors;
        ksort($aReturn);
        return $aReturn;
    }


}