function ServerReportingTest($url, $id, &$sql)
{
echo "Testing server reporting...\n";
$resp = SimpleHEAD::HEADrequest($url);
$useslm = 0;
$usesetag = 0;
if (!isset($resp['lm']) || empty($resp['lm'])) {
echo "The bloody server doesn't report Last-Modified info.\n";
$useslm = false;
} else {
echo "Aw yeah, it supports Last-Modified.\n";
if (!ServerTestPackage::LMReliabilityTest($url)) {
echo "Last-Modified timestamps are unreliable!\n";
$useslm = false;
} else {
echo "Last-Modified timestamps are reliable.\n";
$useslm = true;
}
}
if (!isset($resp['et']) || empty($resp['et'])) {
echo "The bloody server doesn't report ETag info.\n";
$usesetag = false;
} else {
echo "Aw yeah, it supports ETag.\n";
$usesetag = true;
}
echo "Storing these details in the database...";
if ($usesetag === true && $useslm === true) {
// supports both etag and last-modified
$sql->write('feeds', array('reports' => 'complete', 'etag' => $resp['et'], 'lastmodified' => date('Y-m-d H:i:s', strtotime($resp['lm']))), $id);
} elseif ($usesetag === true && $useslm === false) {
// supports only etag (I don't expect this to happen)
$sql->write('feeds', array('reports' => 'etagonly', 'etag' => $resp['et']), $id);
} elseif ($usesetag === false && $useslm === true) {
// supports only last-modified
$sql->write('feeds', array('reports' => 'lmonly', 'lastmodified' => date('Y-m-d H:i:s', strtotime($resp['lm']))), $id);
} elseif ($usesetag === false && $useslm === false) {
// supports neither etag nor last-modified (bad server!)
$sql->write('feeds', array('reports' => 'none'), $id);
} else {
// ambiguous test results
die("Ambiguous test results: useslm = {$useslm}, usesetag = {$usesetag}.\n");
}
echo "Done.\n";
}
function RSSReader_activate()
{
ini_set('error_reporting', E_ALL);
ini_set('display_errors', 1);
require_once "{$GLOBALS['PROJECT_BASEDIR']}/libs/TempStore.php";
// abstracts data storage
// returns MySQL valid timestamp
function mysql_time($t)
{
return date('Y-m-d H:i:s', $t);
}
// prints out fetched key=>val pairs
function printarr($arr)
{
foreach ($arr as $k => $v) {
if (is_array($v)) {
printarr($v);
} else {
echo "<tr>\n\t<td>«{$k}»</td>\n\t<td>«" . htmlspecialchars($v, ENT_COMPAT, 'UTF-8') . "»</td>\n</tr>\n";
}
}
}
// CONSTANTS AND HANDLES
$shortwait = 10;
// time in seconds between each check for new content on well reporting servers (10*60 is a good value here)
$longwait = 30;
// time in seconds between each redownload of content on servers not reporting content information (30*60 is a good value here)
$sql =& new DBXStore($GLOBALS['DB_HOST'], $GLOBALS['DB_USERNAME'], $GLOBALS['DB_PASSWORD'], $GLOBALS['DB_DATABASE']);
// data storage handle
$feeds = $sql->read('feeds', array('id', 'url', 'timer', 'lastmodified', 'etag', 'reports'));
// cache of all relevant information from data storage
$ett = null;
// I have to get the ETag we got from the server to the data writing bit somehow...
$lmm = null;
// I have to get the Last-Modified timestamp we got from the server to the data writing bit somehow...
$update = false;
// This also needs a default value to avoid notices--I don't want ANY errors. ;)
//________________________________________________________________
//================================================================
//
// MAIN LOOP
//________________________________________________________________
//================================================================
foreach ($feeds->data as $feed) {
// Check to see if it's time to update this feed
$checkhead = false;
$ett = null;
// clear out old ETag availability value
$lmm = null;
// clear out old Last-Modified availability value
if ($feed['reports'] == 'complete' || $feed['reports'] == 'etagonly' || $feed['reports'] == 'lmonly') {
// Server reports some usable information, we can make HEAD requests after a short wait time
if ($feed['timer'] == 0 || empty($feed['timer']) || $feed['timer'] == null || strtotime($feed['timer']) + $shortwait < time()) {
// Time since last update longer than required short wait time, or not set timestamp
$checkhead = true;
}
} else {
// Either reports 'none' (bad server!) or not tested, only check after long wait time has passed
if ($feed['timer'] == 0 || empty($feed['timer']) || $feed['timer'] == null || strtotime($feed['timer']) + $longwait < time()) {
// Time since last update longer than required long wait time, or not set timestamp
$checkhead = true;
}
}
if ($checkhead == true) {
// about time to make a new HEAD request
if ($feed['reports'] == 'complete' || $feed['reports'] == 'etagonly') {
// etag checking here
$resp = SimpleHEAD::HEADrequest($feed['url']);
if (!isset($feed['etag']) || empty($feed['etag']) || $feed['etag'] == null || !isset($resp['et']) || empty($resp['et']) || $resp['et'] == null) {
echo "Got no ETag to compare with; proceeding with download.\n";
$update = true;
} elseif (isset($feed['etag']) && isset($resp['et']) && !empty($resp['et']) && $resp['et'] != null && $feed['etag'] == $resp['et']) {
echo "Cool, these ETags are equal! No need to update.\n";
$update = false;
// we can't check ALL the time!
$sql->write('feeds', array('timer' => mysql_time(time())), $feed['id']);
$ett = $resp['et'];
// I have to get this to the data writing bit somehow...
} elseif (isset($feed['etag']) && isset($resp['et']) && !empty($resp['et']) && $feed['etag'] != null && $feed['etag'] != $resp['et']) {
echo "These ETags are different; proceeding with download.\n";
echo $feed['etag'] . ' - ' . $resp['et'] . "\n";
$update = true;
$ett = $resp['et'];
// I have to get this to the data writing bit somehow...
} else {
// Something I failed to think about?
die("This sure is an interesting error. (Check the ETag code of " . __FILE__ . " at " . __LINE__ . ".\n");
}
if ($feed['reports'] == 'complete') {
$lmm = $resp['lm'];
// don't forget to store this if we have it
}
} elseif ($feed['reports'] == 'lmonly') {
// lm checking here
$resp = SimpleHEAD::HEADrequest($feed['url']);
if (isset($resp['lm']) && !empty($resp['lm'])) {
$lmm = strtotime($resp['lm']);
}
if (!isset($feed['lastmodified']) || strtotime($feed['lastmodified']) == 0 || !isset($resp['lm']) || empty($resp['lm'])) {
echo "Got no Last-Modified timestamp to compare with; proceeding with download.\n";
$update = true;
} elseif (isset($feed['lastmodified']) && $lmm != 0 && strtotime($feed['lastmodified']) == $lmm) {
echo "Cool, these Last-Modified timestamps are equal! No need to update.\n";
$update = false;
// we can't check ALL the time!
$sql->write('feeds', array('timer' => mysql_time(time())), $feed['id']);
} elseif (isset($feed['lastmodified']) && $lmm != 0 && strtotime($feed['lastmodified']) != $lmm) {
echo "These timestamps are different; proceeding with download.\n";
echo strtotime($feed['lastmodified']) . ' - ' . $lmm . "\n";
$update = true;
} else {
// Something I failed to think about?
die("This sure is an interesting error. (Check the Last-Modified code of " . __FILE__ . " at " . __LINE__ . ".\n");
}
} elseif ($feed['reports'] == 'none' || $feed['reports'] == null) {
if ($feed['reports'] == null) {
ServerTestPackage::ServerReportingTest($feed['url'], $feed['id'], $sql);
}
$ett = null;
// reset these before writing
$lmm = null;
// reset these before writing
// no way to check if anything's new... we'll just have to download the whole thing
$update = true;
} else {
// ambiguous database value for 'reports'
die("Ambiguous database value for 'reports': feed['reports'] = {$feed['reports']}.\n");
}
} else {
// from if($checkhead)
// too soon to update, we'll just give out a little notice
if ($feed['reports'] == 'complete' || $feed['reports'] == 'etagonly' || $feed['reports'] == 'lmonly') {
// short wait time
echo "LOL! Too soon d00d.\n" . Duration::toString(time() - strtotime($feed['timer'])) . " since last update. You just gotta wait " . Duration::toString(strtotime($feed['timer']) + $shortwait - time()) . " more.\n";
} else {
// long wait time
echo "OMG! Too soon d00d.\n" . Duration::toString(time() - strtotime($feed['timer'])) . " since last update. You just gotta wait " . Duration::toString(strtotime($feed['timer']) + $longwait - time()) . " more.\n";
}
}
// end if($checkhead)
if ($update) {
$rss =& new XML_RSS($feed['url']);
$rss->parse();
echo '<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset="utf-8" />
<title>Test</title>
</head>
<body>
<table>';
printarr($rss->getChannelInfo());
echo ' </table>
</body>
</html>
';
// we've updated, now write a new timestamp
if (isset($ett) && !empty($ett) && isset($lmm) && !empty($lmm)) {
// Got both ETag and Last-Modified from server (bravo!)
// write the current time, the ETag we got, and the Last-Modified timestamp we got
$sql->write('feeds', array('timer' => mysql_time(time()), 'etag' => $ett, 'lastmodified' => mysql_time($lmm)), $feed['id']);
} elseif (isset($ett) && !empty($ett)) {
// Only got ETag from server
// write the current time and the ETag we got
$sql->write('feeds', array('timer' => mysql_time(time()), 'etag' => $ett), $feed['id']);
} elseif (isset($lmm) && !empty($lmm)) {
// Only got Last-Modified from server
// write the current time and the Last-Modified timestamp we got
$sql->write('feeds', array('timer' => mysql_time(time()), 'lastmodified' => mysql_time($lmm)), $feed['id']);
} else {
// Got no content information from server (bad server!)
// just write the current time
$sql->write('feeds', array('timer' => mysql_time(time())), $feed['id']);
}
}
}
// end main loop
}
