.gitignore

Predis.php
Predis_Compatibility.php

client-add.php

<?php
require 'Predis.php';

$key1 = "key1"; #should come up with a good name.
$key2 = "key2";
$millis = time() * 1000;
print "time: $millis\r\n";
$event = "Hello World $millis";
// print_r($event);
$redis = new Predis_Client();
$oldfirst = $redis->zrange($key1, 0, 0);
print "oldfirst\r\n";
print_r($oldfirst);
$redis->zadd($key1, $millis, $event);
#Get event which has to be scheduled first
$first = $redis->zrange($key1, 0, 0);
print "first\r\n";
print_r($first);

if ($first[0] != null && $oldfirst == null || $oldfirst <> $first) { 
    #got different first event => notify wakeup.php.    
    print "diff\r\n";
    $redis->lpush($key2, $first[0]);
} else {
    print "same\r\n";
}

wakeup.php

<?php

require 'Predis.php';

$redis = new Predis_Client();
$key1 = "key1";
$key2 = "key2";
$timeout = 5;

while(true) {
    $first = $redis->blpop($key2, $timeout);
    print_r($first);
    print "\r\n";
}