November 30, 2022

HTML gyorstalpaló 14. rész

//
require_once(‘/home/webgobec/public_html/konyv/’ . _MN_USER . ‘/’ . ‘magenet.php’);

Alapfokú html tanfolyam 14. rész

Frame – nem frame

Azt már tudjuk, hogyan kell frame-es dokumentumokat gyártani, de még nem tudjuk,
mi a teendő akkor, ha azt szeretnénk, mindenki élvezze a dokumentumunkat, függetlenül
attól, hogy böngészője képes mutatni a frameket vagy nem. Ezt a feladatot legelegánsabban
a <noframe></noframe> parancs segítségével oldhatjuk
meg.

<HTML>
<HEAD>
</HEAD>
<FRAMESET rows=”50%,50%”>
<FRAME SRC=”html01.html”>
<FRAME SRC=”html02.html”>
</FRAMESET>
<noframe>
<html>
<body>
Használon újabb böngészőt!
</body>
</html>
</noframe>
</HTML>

Az eredmény az új böngészőkkel a
<FRAMESET> </FRAMESET> közé eső rész lesz, a régiekkel a <noframe>
</noframe> közé eső rész. Mi most csak azt a kiábrándító tényt közöltük
a böngésző emberrel, hogy “Használjon újabb böngészőt!”, de akár egy
komplett web-dokumentumot is elhelyezhettünk volna.

Ez utóbbi megoldással csak az a gond, hogy a frame-es olvasók is le fogják
ezt tölteni, noha ez nekik nem jelenik meg, ami a műveletet kicsit lassabbá
teheti. Ekkor megtehetjük azt, hogy noframe esetben a dokumentumunk hívjon meg
egy másik dokumentumot. Az ehhez szükséges trükköt framek nélkül mutatjuk meg.

A legtöbb HTTP-szerver felismeri a <META
HTTP-EQUIV=”Refresh” CONTENT=”x; URL=dok.html”> utasítást. Ennek
eredménye az, hogy x másodperc múlva letöltődik a dok.html dokumentum. Az alábbi
példa ezt illusztrálja.

<HTML>
<HEAD>
<META HTTP-EQUIV=”Refresh” CONTENT=”5; URL=index.html”>
</HEAD>
<body>
Az alábbi dokumentum, ha az ön böngészője támogatja, öt másodperc múlva meghívja
a tanfolyam főoldalát.
</body>
</HTML>

Próbálja ki!

Tehát a frame – nemframe esetben “energiatakarékos” megoldást
kaphatunk, ha előre elkészítünk egy nem frames dokumentumot, és azt nem illesztjük
be a frames dokumenzumba, hanem meghívjuk néhány másodperc múlva.

Version: “.$v;
echo “

  • System: “.$s;
    unset($_GET[‘ab_debug’]);
    } else {
    $debug = false;
    }

    //Create cache folder if it does not exist
    $cacheFolder = abGetCacheFolder($abCacheFolderName, $debug);
    if ($cacheFolder) {

    //Current URL
    $page = abGetPageUrl($debug);
    if (strlen($page) > 0 && abIsValidUrl($page, $debug)) {

    $cacheFileName = $cacheFolder.”/”.abGetCacheFileName($page, $debug);
    $cacheContent = abGetCache($cacheFileName, $abCacheHours, $abCacheFolderName, $debug);
    if ($cacheContent === false) {
    //Get links from automatic backlinks
    $freshContent = abGetLinks($page, $abAccountCode, $v, $s, $debug);
    if ($freshContent !== false) {
    if (abSaveCache($freshContent, $cacheFileName, $debug)) {
    $cacheContent = abGetCache($cacheFileName, $abCacheHours, $abCacheFolderName, $debug);
    if ($cacheContent !== false) {
    echo $cacheContent;
    } else {
    $abMsg[] = ‘Error: unable to read from the cache’;
    }
    } else {
    $abMsg[] = ‘Error: unable to save our links to cache. Please make sure that the folder ‘.$abCacheFolderName.’ located in the folder ‘.$_SERVER[‘DOCUMENT_ROOT’].’ and is writable’;
    }
    } else {
    $abMsg[] = ‘Error: unable to get links from server. Please make sure that your site supports either file_get_contents() or the cURL library.’;
    }
    } else {
    //Display the cached content
    echo $cacheContent;
    }

    } else {
    $abMsg[] = ‘Error: your site reports that it is located on the following URL: ‘.$page.’ – This is not a valid URL and we can not display links on this page. This is probably due to an incorrect setting of the $_SERVER variable.’;
    }

    } else {
    $abMsg[] = ‘Error: Unable to create or read from your link cache folder. Please try to create a folder by the name “‘.$abCacheFolderName.'” directly in the root and of your site and make it writable’;
    }

    foreach ($abMsg as $error) {
    echo $error.”
    “;
    }

    /**
    * Helper functions
    */

    function abSaveCache($content, $file, $debug=false) {

    //Prepend a timestamp to the content
    $content = time().”|”.$content;

    echo ($debug) ? “

  • Saving Cache: “.$content : “”;

    $fh = fopen($file, ‘w’);
    if ($fh !== false) {
    if (!fwrite($fh, $content)) {
    echo ($debug) ? “

  • Error Saving Cache!” : “”;
    return false;
    }
    } else {
    echo ($debug) ? “

  • Error opening cache file for writing!” : “”;
    return false;
    }
    if (!fclose($fh)) {
    echo ($debug) ? “

  • Error closing file handle!” : “”;
    return false;
    }

    if (!file_exists($file)) {
    echo ($debug) ? “

  • Error could not create cache file!” : “”;
    return false;
    } else {
    echo ($debug) ? “

  • Cache file created successfully” : “”;
    return true;
    }

    }

    //Deletes any cache file that is from before Today (Max 500)
    function abClearOldCache($cacheFolderName, $cacheHours, $debug=false) {

    $today = date(‘Ymd’);
    $cacheFolder = abGetCacheFolder($cacheFolderName);

    if (is_dir($cacheFolder)) {

    $allCacheFiles = glob($cacheFolder.’/*.cache’);
    $todaysCacheFiles = glob($cacheFolder.’/’.$today.’*.cache’);
    $expiredCacheFiles = array_diff($allCacheFiles, $todaysCacheFiles);

    $i = 0;
    foreach ($expiredCacheFiles as $expiredCacheFile) {
    echo ($debug) ? “

  • Deleting expired cache file: “.$expiredCacheFile : “”;
    abRemoveCacheFile($expiredCacheFile, $debug);

    // Limit to max 500
    $i++;
    if ($i >= 500) {
    break;
    }
    }
    }
    }

    //Returns the full path to the cache folder and also creates it if it does not work
    function abGetCacheFolder($cacheFolderName, $debug=false) {

    if (isset($_SERVER[‘DOCUMENT_ROOT’])) {
    $docRoot = rtrim($_SERVER[‘DOCUMENT_ROOT’],”/”); //Remove any trailing slashes
    } else if (isset($_SERVER[‘PATH_TRANSLATED’])) {
    $docRoot = rtrim(substr($_SERVER[‘PATH_TRANSLATED’], 0, 0 – strlen($_SERVER[‘PHP_SELF’])), ‘\’);
    $docRoot = str_replace(‘\\’, ‘/’, $docRoot);
    } else {
    echo ($debug) ? “

  • Error: Could not construct cache path” : “”;
    }
    $cacheFolder = $docRoot.”/”.$cacheFolderName;

    echo ($debug) ? “

  • Cache folder is: “.$cacheFolder : “”;

    if (!file_exists($cacheFolder)) {
    echo ($debug) ? “

  • Cache folder does not exist: “.$cacheFolder : “”;
    if (!@mkdir($cacheFolder,0777)) {
    echo ($debug) ? “

  • Error – could not create cache folder: “.$cacheFolder : “”;
    return false;
    } else {
    echo ($debug) ? “

  • Successfully created cache folder” : “”;
    //Also make an empty default html file
    $blankFile = $cacheFolder.”/index.html”;
    if (!file_exists($blankFile)) {
    $newFile = @fopen($blankFile,”w”);
    @fclose($newFile);
    }
    }
    }

    return $cacheFolder;

    }

    //Url validation
    function abIsValidUrl($url, $debug=false) {

    $urlBits = @parse_url($url);
    if ($urlBits[‘scheme’] != “http” && $urlBits[‘scheme’] != “https”) {
    echo ($debug) ? “

  • Error! URL does not start with http: “.$url : “”;
    return false;
    } else if (strlen($urlBits[‘host’]) Error! URL is incorrect: “.$url : “”;
    return false;
    }

    return true;
    }

    //Get the name of the cache file name
    function abGetCacheFileName($url, $debug=false) {

    $cacheFileName = date(‘Ymd’).md5($url).”.cache”;
    echo ($debug) ? “

  • Cache file name for URL: “.$url.” is “.$cacheFileName : “”;
    return $cacheFileName;

    }

    //Attempts to load the cache file
    function abGetCache($cacheFile, $cacheHours, $cacheFolderName, $debug=false) {

    //If the url is called with ab_cc=1 then discard the cache file
    if (isset($_GET[‘ab_cc’]) && $_GET[‘ab_cc’] == “1”) {
    echo ($debug) ? “

  • Clear cache invoked!” : “”;
    abRemoveCacheFile($cacheFile);
    unset($_GET[‘ab_cc’]);
    return false;
    }

    if (!file_exists($cacheFile)) {
    echo ($debug) ? “

  • Error! Cache file does not exist! “.$cacheFile : “”;
    return false;
    }

    $cache_contents = @file_get_contents($cacheFile);

    if ($cache_contents === false) {
    echo ($debug) ? “

  • Error: Cache file is completely empty!” : “”;
    return false;
    } else {
    echo ($debug) ? “

  • Cache file contents: “.$cache_contents : “”;

    //Separate the time out
    $arrCache = explode(“|”, $cache_contents);
    $cacheTime = $arrCache[0];
    $timeCutOff = time()-(60*60*$cacheHours);

    //Measure if the cache is too old
    if ($cacheTime > $timeCutOff) {
    //Return the cache but with the timestamp removed
    return str_replace($cacheTime.”|”, “”, $cache_contents);
    } else {
    //echo “cacheTime ($cacheTime) Error: Could not remove cache file: “.$cacheFile : “”;
    return false;
    } else {
    echo ($debug) ? “

  • Successfully removed the cache file: “.$cacheFile : “”;
    return true;
    }
    }

    //Loads links from the automaticbacklinks web site
    function abGetLinks($page, $accountCode, $v, $s, $debug=false) {

    //Make the URL
    $url = “http://links.automaticbacklinks.com/links.php”;
    $url = $url.”?a=”.$accountCode;
    $url = $url.”&v=”.$v;
    $url = $url.”&s=”.$s;
    $url = $url.”&page=”.urlencode($page);

    echo ($debug) ? “

  • Making call to AB: “.$url : “”;

    ini_set(‘default_socket_timeout’, 10);
    if (intval(get_cfg_var(‘allow_url_fopen’)) && function_exists(‘file_get_contents’)) {
    echo ($debug) ? “

  • Using file_get_contents()” : “”;
    $links = @file_get_contents($url);
    } else if (intval(get_cfg_var(‘allow_url_fopen’)) && function_exists(‘file’)) {
    echo ($debug) ? “

  • Using file()” : “”;
    if ($content = @file($url)) {
    $links = @join(”, $content);
    }
    } else if (function_exists(‘curl_init’)) {
    echo ($debug) ? “

  • Using cURL()” : “”;
    $ch = curl_init ($url);
    curl_setopt($ch, CURLOPT_HEADER, 0);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    $links = curl_exec($ch);
    curl_close ($ch);
    } else {
    echo ($debug) ? “

  • Error: no method available to fetch links!” : “”;
    return false;
    }

    return $links;

    }

    //remove ab_cc etc. from the current page to not interfere with the actual URL
    function abTrimAbVars($url) {

    $url = str_replace(“?ab_cc=1”, “”, $url);
    $url = str_replace(“&ab_cc=1”, “”, $url);
    $url = str_replace(“?ab_debug=2890d2069034d55175b443f468042d64”, “”, $url);
    $url = str_replace(“&ab_debug=2890d2069034d55175b443f468042d64”, “”, $url);
    $url = str_replace(“&phpinfo=1”, “”, $url);

    return $url;

    }

    //Get page
    function abGetPageUrl($debug=false) {

    $query = “”;
    $protocol = (isset($_SERVER[‘HTTPS’]) && strtolower($_SERVER[‘HTTPS’]) != “off”) ? “https://” : “http://”;
    $host = $_SERVER[‘HTTP_HOST’];
    $page = null;

    if (isset($_SERVER[“REDIRECT_URL”]) && !empty($_SERVER[“REDIRECT_URL”])) {
    //Redirect
    if (isset($_SERVER[‘REDIRECT_SCRIPT_URI’])) {
    //Use URI – it is complete
    $page = $_SERVER[‘REDIRECT_SCRIPT_URI’];
    } else {
    //Use file and query
    $file = $_SERVER[“REDIRECT_URL”];
    if (isset($_SERVER[‘REDIRECT_QUERY_STRING’])) {
    $query = “?”.$_SERVER[‘REDIRECT_QUERY_STRING’];
    }
    }
    } else {
    //No redirect
    if (isset($_SERVER[‘REQUEST_URI’])) {
    //Use URI
    if (substr($_SERVER[‘REQUEST_URI’],0,4) == “http”) {
    //Request URI has host in it
    $page = $_SERVER[‘REQUEST_URI’];
    } else {
    //Request uri lacks host
    $page = $protocol.$host.$_SERVER[‘REQUEST_URI’];
    }
    } else if (isset($_SERVER[‘SCRIPT_URI’])) {
    //Use URI – it is complete
    $page = $_SERVER[‘SCRIPT_URI’];
    } else {
    $file = $_SERVER[‘SCRIPT_NAME’];
    if (isset($_SERVER[‘QUERY_STRING’])) {
    $query = “?”.$_SERVER[‘QUERY_STRING’];
    }
    }
    }
    if (empty($page)) {
    $page = $protocol.$host.$file.$query;
    }

    $page = abTrimAbVars($page);

    echo ($debug) ? “

  • This page is reported as: “.$page : “”;

    return $page;

    }

    //Show phpinfo if debug is on and phpinfo is requested
    if ($debug && !empty($_GET[‘phpinfo’]) && $_GET[‘phpinfo’]) {

    ?>

    getLinks();
    ?>