lainchan/b.php
Michael Walker afc2d2e4e1 Implement priority banners.
If the directory "banners_priority" exists and contains files, a file
from it is served 33% of the time, an a file from "banners" 66% of the
time.

This may seem like an odd definition of "priority", but assuming far
fewer priority banners than normal banners, this gives them extra weight
in the selection. Before, any 1 banner in 100 had a 1% chance of being
served; now if that banner is a priority banner it has a 33% chance.
2016-08-20 00:54:56 +01:00

48 lines
1.3 KiB
PHP
Executable File

<?php
// This script assumes there is at least one normal (non-priority)
// banner!
// Get the files in a directory, returns null if the directory does
// not exist.
function getFilesInDirectory($dir) {
if (! is_dir($dir)) {
return null;
}
return array_diff(scandir($dir), array('.', '..'));
}
// Serve a random banner and exit.
function serveRandomBanner($dir, $files) {
$name = $files[array_rand($files)];
// snags the extension
$ext = pathinfo($name, PATHINFO_EXTENSION);
// send the right headers
header('Cache-Control: no-cache, no-store, must-revalidate'); // HTTP 1.1
header('Pragma: no-cache'); // HTTP 1.0
header('Expires: 0'); // Proxies
header("Content-type: image/" . ext);
header("Content-Disposition: inline; filename=" . $name);
// readfile displays the image, passthru seems to spits stream.
readfile($dir.$name);
exit;
}
// Get all the banners
$bannerDir = "banners/";
$priorityDir = "banners_priority/";
$banners = getFilesInDirectory($bannerDir);
$priority = getFilesInDirectory($priorityDir);
// If there are priority banners, serve 1/3rd of the time.
if($priority !== null && count($priority) !== 0 && rand(0,2) === 0) {
serveRandomBanner($priorityDir, $priority);
}
serveRandomBanner($bannerDir, $banners);
?>