function client_thread($self)
{
$context = new ZMQContext();
$client = new ZMQSocket($context, ZMQ::SOCKET_REQ);
$endpoint = sprintf("ipc://%s-localfe.ipc", $self);
$client->connect($endpoint);
$monitor = new ZMQSocket($context, ZMQ::SOCKET_PUSH);
$endpoint = sprintf("ipc://%s-monitor.ipc", $self);
$monitor->connect($endpoint);
$readable = $writeable = array();
while (true) {
sleep(mt_rand(0, 4));
$burst = mt_rand(1, 14);
while ($burst--) {
// Send request with random hex ID
$task_id = sprintf("%04X", mt_rand(0, 10000));
$client->send($task_id);
// Wait max ten seconds for a reply, then complain
$poll = new ZMQPoll();
$poll->add($client, ZMQ::POLL_IN);
$events = $poll->poll($readable, $writeable, 10 * 1000000);
if ($events > 0) {
foreach ($readable as $socket) {
$zmsg = new Zmsg($socket);
$zmsg->recv();
// Worker is supposed to answer us with our task id
assert($zmsg->body() == $task_id);
}
} else {
$monitor->send(sprintf("E: CLIENT EXIT - lost task %s", $task_id));
exit;
}
}
}
}
function client_task()
{
$context = new ZMQContext();
$client = new ZMQSocket($context, ZMQ::SOCKET_DEALER);
// Generate printable identity for the client
$identity = sprintf("%04X", rand(0, 0x10000));
$client->setSockOpt(ZMQ::SOCKOPT_IDENTITY, $identity);
$client->connect("tcp://localhost:5570");
$read = $write = array();
$poll = new ZMQPoll();
$poll->add($client, ZMQ::POLL_IN);
$request_nbr = 0;
while (true) {
// Tick once per second, pulling in arriving messages
for ($centitick = 0; $centitick < 100; $centitick++) {
$events = $poll->poll($read, $write, 1000);
$zmsg = new Zmsg($client);
if ($events) {
$zmsg->recv();
printf("%s: %s%s", $identity, $zmsg->body(), PHP_EOL);
}
}
$zmsg = new Zmsg($client);
$zmsg->body_fmt("request #%d", ++$request_nbr)->send();
}
}
/**
* Run a self test of the Zmsg class.
*
* @return boolean
* @todo See if assert returns
*/
public static function test()
{
$result = true;
$context = new ZMQContext();
$output = new ZMQSocket($context, ZMQ::SOCKET_XREQ);
$output->bind("inproc://zmsg_selftest");
$input = new ZMQSocket($context, ZMQ::SOCKET_XREP);
$input->connect("inproc://zmsg_selftest");
// Test send and receive of single-part message
$zmsgo = new Zmsg($output);
$zmsgo->body_set("Hello");
$result &= assert($zmsgo->body() == "Hello");
$zmsgo->send();
$zmsgi = new Zmsg($input);
$zmsgi->recv();
$result &= assert($zmsgi->parts() == 2);
$result &= assert($zmsgi->body() == "Hello");
echo $zmsgi;
// Test send and receive of multi-part message
$zmsgo = new Zmsg($output);
$zmsgo->body_set("Hello");
$zmsgo->wrap("address1", "");
$zmsgo->wrap("address2");
$result &= assert($zmsgo->parts() == 4);
echo $zmsgo;
$zmsgo->send();
$zmsgi = new Zmsg($input);
$zmsgi->recv();
$result &= assert($zmsgi->parts() == 5);
$zmsgi->unwrap();
$result &= assert($zmsgi->unwrap() == "address2");
$zmsgi->body_fmt("%s%s", 'W', "orld");
$result &= assert($zmsgi->body() == "World");
// Pull off address 1, check that empty part was dropped
$zmsgi->unwrap();
$result &= assert($zmsgi->parts() == 1);
// Check that message body was correctly modified
$part = $zmsgi->pop();
$result &= assert($part == "World");
$result &= assert($zmsgi->parts() == 0);
// Test load and save
$zmsg = new Zmsg();
$zmsg->body_set("Hello");
$zmsg->wrap("address1", "");
$zmsg->wrap("address2");
$result &= assert($zmsg->parts() == 4);
$fh = fopen(sys_get_temp_dir() . "/zmsgtest.zmsg", 'w');
$zmsg->save($fh);
fclose($fh);
$fh = fopen(sys_get_temp_dir() . "/zmsgtest.zmsg", 'r');
$zmsg2 = new Zmsg();
$zmsg2->load($fh);
assert($zmsg2->last() == $zmsg->last());
fclose($fh);
$result &= assert($zmsg2->parts() == 4);
echo $result ? "OK" : "FAIL", PHP_EOL;
return $result;
}
// Get message
// - 3-part envelope + content -> request
// - 1-part "HEARTBEAT" -> heartbeat
$zmsg = new Zmsg($worker);
$zmsg->recv();
if ($zmsg->parts() == 3) {
// Simulate various problems, after a few cycles
$cycles++;
if ($cycles > 3 && rand(0, 5) == 0) {
printf("I: (%s) simulating a crash%s", $identity, PHP_EOL);
break;
} elseif ($cycles > 3 && rand(0, 5) == 0) {
printf("I: (%s) simulating CPU overload%s", $identity, PHP_EOL);
sleep(5);
}
printf("I: (%s) normal reply - %s%s", $identity, $zmsg->body(), PHP_EOL);
$zmsg->send();
$liveness = HEARTBEAT_LIVENESS;
sleep(1);
// Do some heavy work
} elseif ($zmsg->parts() == 1 && $zmsg->body() == 'HEARTBEAT') {
$liveness = HEARTBEAT_LIVENESS;
} else {
printf("E: (%s) invalid message%s%s", $identity, PHP_EOL, $zmsg->__toString());
}
$interval = INTERVAL_INIT;
} elseif (--$liveness == 0) {
printf("W: (%s) heartbeat failure, can't reach queue%s", $identity, PHP_EOL);
printf("W: (%s) reconnecting in %d msec...%s", $identity, $interval, PHP_EOL);
usleep($interval * 1000);
if ($interval < INTERVAL_MAX) {
function main()
{
for ($client_nbr = 0; $client_nbr < NBR_CLIENTS; $client_nbr++) {
$pid = pcntl_fork();
if ($pid == 0) {
client_thread();
return;
}
}
for ($worker_nbr = 0; $worker_nbr < NBR_WORKERS; $worker_nbr++) {
$pid = pcntl_fork();
if ($pid == 0) {
worker_thread();
return;
}
}
$context = new ZMQContext();
$frontend = new ZMQSocket($context, ZMQ::SOCKET_ROUTER);
$backend = new ZMQSocket($context, ZMQ::SOCKET_ROUTER);
$frontend->bind("ipc://frontend.ipc");
$backend->bind("ipc://backend.ipc");
// Logic of LRU loop
// - Poll backend always, frontend only if 1+ worker ready
// - If worker replies, queue worker as ready and forward reply
// to client if necessary
// - If client requests, pop next worker and send request to it
// Queue of available workers
$available_workers = 0;
$worker_queue = array();
$writeable = $readable = array();
while ($client_nbr > 0) {
$poll = new ZMQPoll();
// Poll front-end only if we have available workers
if ($available_workers > 0) {
$poll->add($frontend, ZMQ::POLL_IN);
}
// Always poll for worker activity on backend
$poll->add($backend, ZMQ::POLL_IN);
$events = $poll->poll($readable, $writeable);
if ($events > 0) {
foreach ($readable as $socket) {
// Handle worker activity on backend
if ($socket === $backend) {
// Queue worker address for LRU routing
$zmsg = new Zmsg($socket);
$zmsg->recv();
assert($available_workers < NBR_WORKERS);
$available_workers++;
array_push($worker_queue, $zmsg->unwrap());
if ($zmsg->body() != "READY") {
$zmsg->set_socket($frontend)->send();
// exit after all messages relayed
$client_nbr--;
}
} else {
if ($socket === $frontend) {
$zmsg = new Zmsg($socket);
$zmsg->recv();
$zmsg->wrap(array_shift($worker_queue), "");
$zmsg->set_socket($backend)->send();
$available_workers--;
}
}
}
}
}
// Clean up our worker processes
foreach ($worker_queue as $worker) {
$zmsg = new Zmsg($backend);
$zmsg->body_set('END')->wrap($worker, "")->send();
}
sleep(1);
}
*
* @author Ian Barber <ian(dot)barber(at)gmail(dot)com>
*/
include 'zmsg.php';
$context = new ZMQContext();
$worker = new ZMQSocket($context, ZMQ::SOCKET_REQ);
// Set random identity to make tracing easier
$identity = sprintf("%04X-%04X", rand(0, 0x10000), rand(0, 0x10000));
$worker->setSockOpt(ZMQ::SOCKOPT_IDENTITY, $identity);
$worker->connect("tcp://localhost:5556");
// Tell queue we're ready for work
printf("I: (%s) worker ready%s", $identity, PHP_EOL);
$worker->send("READY");
$cycles = 0;
while (true) {
$zmsg = new Zmsg($worker);
$zmsg->recv();
$cycles++;
// Simulate various problems, after a few cycles
if ($cycles > 3 && rand(0, 3) == 0) {
printf("I: (%s) simulating a crash%s", $identity, PHP_EOL);
break;
} elseif ($cycles > 3 && rand(0, 3) == 0) {
printf("I: (%s) simulating CPU overload%s", $identity, PHP_EOL);
sleep(5);
}
printf("I: (%s) normal reply - %s%s", $identity, $zmsg->body(), PHP_EOL);
sleep(1);
// Do some heavy work
$zmsg->send();
}
