Examples

Example #1 Simple HTTP client

<?php
// Read callback
function readcb($bev, $base) {
    //$input = $bev->input; //$bev->getInput();

    //$pos = $input->search("TTP");
    $pos = $bev->input->search("TTP");

    while (($n = $bev->input->remove($buf, 1024)) > 0) {
        echo $buf;
    }
}

// Event callback
function eventcb($bev, $events, $base) {
    if ($events & EventBufferEvent::CONNECTED) {
        echo "Connected.\n";
    } elseif ($events & (EventBufferEvent::ERROR | EventBufferEvent::EOF)) {
        if ($events & EventBufferEvent::ERROR) {
            echo "DNS error: ", $bev->getDnsErrorString(), PHP_EOL;
        }

        echo "Closing\n";
        $base->exit();
        exit("Done\n");
    }
}

if ($argc != 3) {
    echo <<<EOS
Trivial HTTP 0.x client
Syntax: php {$argv[0]} [hostname] [resource]
Example: php {$argv[0]} www.google.com /

EOS;
    exit();
}

$base = new EventBase();

$dns_base = new EventDnsBase($base, TRUE); // We'll use async DNS resolving
if (!$dns_base) {
    exit("Failed to init DNS Base\n");
}

$bev = new EventBufferEvent($base, /* use internal socket */ NULL,
    EventBufferEvent::OPT_CLOSE_ON_FREE | EventBufferEvent::OPT_DEFER_CALLBACKS,
    "readcb", /* writecb */ NULL, "eventcb"
);
if (!$bev) {
    exit("Failed creating bufferevent socket\n");
}

//$bev->setCallbacks("readcb", /* writecb */ NULL, "eventcb", $base);
$bev->enable(Event::READ | Event::WRITE);

$output = $bev->output; //$bev->getOutput();
if (!$output->add(
    "GET {$argv[2]} HTTP/1.0\r\n".
    "Host: {$argv[1]}\r\n".
    "Connection: Close\r\n\r\n"
)) {
    exit("Failed adding request to output buffer\n");
}

if (!$bev->connectHost($dns_base, $argv[1], 80, EventUtil::AF_UNSPEC)) {
    exit("Can't connect to host {$argv[1]}\n");
}

$base->dispatch();
?>

The above example will output something similar to:

Connected.
HTTP/1.1 301 Moved Permanently
Date: Fri, 01 Mar 2013 18:47:48 GMT
Location: http://www.google.co.uk/
Content-Type: text/html; charset=UTF-8
Cache-Control: public, max-age=2592000
Server: gws
Content-Length: 221
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
Age: 133438
Expires: Sat, 30 Mar 2013 05:39:28 GMT
Connection: close

<HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8">
<TITLE>301 Moved</TITLE></HEAD><BODY>
<H1>301 Moved</H1>
The document has moved
<A HREF="http://www.google.co.uk/">here</A>.
</BODY></HTML>
Closing
Done

Example #2 HTTP client using asynchronous DNS resolver

<?php
/*
 * 1. Connect to 127.0.0.1 at port 80
 * by means of EventBufferEvent::connect().
 *
 * 2. Request /index.cphp via HTTP/1.0
 * using the output buffer.
 *
 * 3. Asyncronously read the response and print it to stdout.
 */

// Read callback
function readcb($bev, $base) {
    $input = $bev->getInput();

    while (($n = $input->remove($buf, 1024)) > 0) {
        echo $buf;
    }
}

// Event callback
function eventcb($bev, $events, $base) {
    if ($events & EventBufferEvent::CONNECTED) {
        echo "Connected.\n";
    } elseif ($events & (EventBufferEvent::ERROR | EventBufferEvent::EOF)) {
        if ($events & EventBufferEvent::ERROR) {
            echo "DNS error: ", $bev->getDnsErrorString(), PHP_EOL;
        }

        echo "Closing\n";
        $base->exit();
        exit("Done\n");
    }
}

$base = new EventBase();

echo "step 1\n";
$bev = new EventBufferEvent($base, /* use internal socket */ NULL,
    EventBufferEvent::OPT_CLOSE_ON_FREE | EventBufferEvent::OPT_DEFER_CALLBACKS);
if (!$bev) {
    exit("Failed creating bufferevent socket\n");
}

echo "step 2\n";
$bev->setCallbacks("readcb", /* writecb */ NULL, "eventcb", $base);
$bev->enable(Event::READ | Event::WRITE);

echo "step 3\n";
// Send request
$output = $bev->getOutput();
if (!$output->add(
    "GET /index.cphp HTTP/1.0\r\n".
    "Connection: Close\r\n\r\n"
)) {
    exit("Failed adding request to output buffer\n");
}

/* Connect to the host syncronously.
We know the IP, and don't need to resolve DNS. */
if (!$bev->connect("127.0.0.1:80")) {
    exit("Can't connect to host\n");
}

// Dispatch pending events
$base->dispatch();
?>

Example #3 Echo server

<?php
/*
 * Simple echo server based on libevent's connection listener.
 *
 * Usage:
 * 1) In one terminal window run:
 *
 * $ php listener.php 9881
 *
 * 2) In another terminal window open up connection, e.g.:
 *
 * $ nc 127.0.0.1 9881
 *
 * 3) start typing. The server should repeat the input.
 */

class MyListenerConnection {
    private $bev, $base;

    public function __destruct() {
        $this->bev->free();
    }

    public function __construct($base, $fd) {
        $this->base = $base;

        $this->bev = new EventBufferEvent($base, $fd, EventBufferEvent::OPT_CLOSE_ON_FREE);

        $this->bev->setCallbacks(array($this, "echoReadCallback"), NULL,
            array($this, "echoEventCallback"), NULL);

        if (!$this->bev->enable(Event::READ)) {
            echo "Failed to enable READ\n";
            return;
        }
    }

    public function echoReadCallback($bev, $ctx) {
        // Copy all the data from the input buffer to the output buffer

        // Variant #1
        $bev->output->addBuffer($bev->input);

        /* Variant #2 */
        /*
        $input    = $bev->getInput();
        $output = $bev->getOutput();
        $output->addBuffer($input);
        */
    }

    public function echoEventCallback($bev, $events, $ctx) {
        if ($events & EventBufferEvent::ERROR) {
            echo "Error from bufferevent\n";
        }

        if ($events & (EventBufferEvent::EOF | EventBufferEvent::ERROR)) {
            //$bev->free();
            $this->__destruct();
        }
    }
}

class MyListener {
    public $base,
        $listener,
        $socket;
    private $conn = array();

    public function __destruct() {
        foreach ($this->conn as &$c) $c = NULL;
    }

    public function __construct($port) {
        $this->base = new EventBase();
        if (!$this->base) {
            echo "Couldn't open event base";
            exit(1);
        }

        // Variant #1
        /*
        $this->socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
        if (!socket_bind($this->socket, '0.0.0.0', $port)) {
            echo "Unable to bind socket\n";
            exit(1);
        }
        $this->listener = new EventListener($this->base,
            array($this, "acceptConnCallback"), $this->base,
            EventListener::OPT_CLOSE_ON_FREE | EventListener::OPT_REUSEABLE,
            -1, $this->socket);
         */

        // Variant #2
         $this->listener = new EventListener($this->base,
             array($this, "acceptConnCallback"), $this->base,
             EventListener::OPT_CLOSE_ON_FREE | EventListener::OPT_REUSEABLE, -1,
             "0.0.0.0:$port");

        if (!$this->listener) {
            echo "Couldn't create listener";
            exit(1);
        }

        $this->listener->setErrorCallback(array($this, "accept_error_cb"));
    }

    public function dispatch() {
        $this->base->dispatch();
    }

    // This callback is invoked when there is data to read on $bev
    public function acceptConnCallback($listener, $fd, $address, $ctx) {
        // We got a new connection! Set up a bufferevent for it. */
        $base = $this->base;
        $this->conn[] = new MyListenerConnection($base, $fd);
    }

    public function accept_error_cb($listener, $ctx) {
        $base = $this->base;

        fprintf(STDERR, "Got an error %d (%s) on the listener. "
            ."Shutting down.\n",
            EventUtil::getLastSocketErrno(),
            EventUtil::getLastSocketError());

        $base->exit(NULL);
    }
}

$port = 9808;

if ($argc > 1) {
    $port = (int) $argv[1];
}
if ($port <= 0 || $port > 65535) {
    exit("Invalid port");
}

$l = new MyListener($port);
$l->dispatch();
?>

Example #4 SSL echo server

<?php
/*
 * SSL echo server
 *
 * To test:
 * 1) Run:
 * $ php examples/ssl-echo-server/server.php 9998
 *
 * 2) in another terminal window run:
 * $ socat - SSL:127.0.0.1:9998,verify=1,cafile=examples/ssl-echo-server/cert.pem
 */

class MySslEchoServer {
    public $port,
        $base,
        $bev,
        $listener,
        $ctx;

    function __construct ($port, $host = "127.0.0.1") {
        $this->port = $port;
        $this->ctx = $this->init_ssl();
        if (!$this->ctx) {
            exit("Failed creating SSL context\n");
        }

        $this->base = new EventBase();
        if (!$this->base) {
            exit("Couldn't open event base\n");
        }

        $this->listener = new EventListener($this->base,
            array($this, "ssl_accept_cb"), $this->ctx,
            EventListener::OPT_CLOSE_ON_FREE | EventListener::OPT_REUSEABLE,
            -1, "$host:$port");
        if (!$this->listener) {
            exit("Couldn't create listener\n");
        }

        $this->listener->setErrorCallback(array($this, "accept_error_cb"));
    }
    function dispatch() {
        $this->base->dispatch();
    }

    // This callback is invoked when there is data to read on $bev.
    function ssl_read_cb($bev, $ctx) {
        $in = $bev->input; //$bev->getInput();

        printf("Received %zu bytes\n", $in->length);
        printf("----- data ----\n");
        printf("%ld:\t%s\n", (int) $in->length, $in->pullup(-1));

        $bev->writeBuffer($in);
    }

    // This callback is invoked when some even occurs on the event listener,
    // e.g. connection closed, or an error occurred
    function ssl_event_cb($bev, $events, $ctx) {
        if ($events & EventBufferEvent::ERROR) {
            // Fetch errors from the SSL error stack
            while ($err = $bev->sslError()) {
                fprintf(STDERR, "Bufferevent error %s.\n", $err);
            }
        }

        if ($events & (EventBufferEvent::EOF | EventBufferEvent::ERROR)) {
            $bev->free();
        }
    }

    // This callback is invoked when a client accepts new connection
    function ssl_accept_cb($listener, $fd, $address, $ctx) {
        // We got a new connection! Set up a bufferevent for it.
        $this->bev = EventBufferEvent::sslSocket($this->base, $fd, $this->ctx,
            EventBufferEvent::SSL_ACCEPTING, EventBufferEvent::OPT_CLOSE_ON_FREE);

        if (!$this->bev) {
            echo "Failed creating ssl buffer\n";
            $this->base->exit(NULL);
            exit(1);
        }

        $this->bev->enable(Event::READ);
        $this->bev->setCallbacks(array($this, "ssl_read_cb"), NULL,
            array($this, "ssl_event_cb"), NULL);
    }

    // This callback is invoked when we failed to setup new connection for a client
    function accept_error_cb($listener, $ctx) {
        fprintf(STDERR, "Got an error %d (%s) on the listener. "
            ."Shutting down.\n",
            EventUtil::getLastSocketErrno(),
            EventUtil::getLastSocketError());

        $this->base->exit(NULL);
    }

    // Initialize SSL structures, create an EventSslContext
    // Optionally create self-signed certificates
    function init_ssl() {
        // We *must* have entropy. Otherwise there's no point to crypto.
        if (!EventUtil::sslRandPoll()) {
            exit("EventUtil::sslRandPoll failed\n");
        }

        $local_cert = __DIR__."/cert.pem";
        $local_pk   = __DIR__."/privkey.pem";

        if (!file_exists($local_cert) || !file_exists($local_pk)) {
            echo "Couldn't read $local_cert or $local_pk file.  To generate a key\n",
                "and self-signed certificate, run:\n",
                "  openssl genrsa -out $local_pk 2048\n",
                "  openssl req -new -key $local_pk -out cert.req\n",
                "  openssl x509 -req -days 365 -in cert.req -signkey $local_pk -out $local_cert\n";

            return FALSE;
        }

        $ctx = new EventSslContext(EventSslContext::SSLv3_SERVER_METHOD, array (
             EventSslContext::OPT_LOCAL_CERT  => $local_cert,
             EventSslContext::OPT_LOCAL_PK    => $local_pk,
             //EventSslContext::OPT_PASSPHRASE  => "echo server",
             EventSslContext::OPT_VERIFY_PEER => true,
             EventSslContext::OPT_ALLOW_SELF_SIGNED => false,
        ));

        return $ctx;
    }
}

// Allow to override the port
$port = 9999;
if ($argc > 1) {
    $port = (int) $argv[1];
}
if ($port <= 0 || $port > 65535) {
    exit("Invalid port\n");
}


$l = new MySslEchoServer($port);
$l->dispatch();
?>

Example #5 Signal handler

<?php
/*
Launch it in a terminal window:

$ php examples/signal.php

In another terminal window find out the pid and send SIGTERM, e.g.:

$ ps aux | grep examp
ruslan    3976  0.2  0.0 139896 11256 pts/1    S+   10:25   0:00 php examples/signal.php
ruslan    3978  0.0  0.0   9572   864 pts/2    S+   10:26   0:00 grep --color=auto examp
$ kill -TERM 3976

At the first terminal window you should catch the following:

Caught signal 15
*/
class MyEventSignal {
    private $base;

    function __construct($base) {
        $this->base = $base;
    }

    function eventSighandler($no, $c) {
        echo "Caught signal $no\n";
        event_base_loopexit($c->base);
    }
}

$base = event_base_new();
$c    = new MyEventSignal($base);
$no   = SIGTERM;
$ev   = evsignal_new($base, $no, array($c,'eventSighandler'), $c);

evsignal_add($ev);

event_base_loop($base);
?>

Example #6 Use libevent's loop to process requests of `eio' extension

<?php
// Callback for eio_nop()
function my_nop_cb($d, $r) {
    echo "step 6\n";
}

$dir = "/tmp/abc-eio-temp";
if (file_exists($dir)) {
    rmdir($dir);
}

echo "step 1\n";

$base = new EventBase();

echo "step 2\n";

eio_init();

eio_mkdir($dir, 0750, EIO_PRI_DEFAULT, "my_nop_cb");

$event = new Event($base, eio_get_event_stream(),
    Event::READ | Event::PERSIST, function ($fd, $events, $base) {
    echo "step 5\n";

    while (eio_nreqs()) {
        eio_poll();
    }

    $base->stop();
}, $base);

echo "step 3\n";

$event->add();

echo "step 4\n";

$base->dispatch();

echo "Done\n";
?>

Example #7 Miscellaneous

<?php
/* {{{ Config & supported stuff */
echo "Supported methods:\n";
foreach (Event::getSupportedMethods() as $m) {
    echo $m, PHP_EOL;
}

// Avoiding "select" method
$cfg = new EventConfig();
if ($cfg->avoidMethod("select")) {
    echo "'select' method avoided\n";
}

// Create event_base associated with the config
$base = new EventBase($cfg);
echo "Event method used: ", $base->getMethod(), PHP_EOL;

echo "Features:\n";
$features = $base->getFeatures();
($features & EventConfig::FEATURE_ET) and print "ET - edge-triggered IO\n";
($features & EventConfig::FEATURE_O1) and print "O1 - O(1) operation for adding/deleting events\n";
($features & EventConfig::FEATURE_FDS) and print "FDS - arbitrary file descriptor types, and not just sockets\n";

// Require FDS feature
if ($cfg->requireFeatures(EventConfig::FEATURE_FDS)) {
    echo "FDS feature is now required\n";

    $base = new EventBase($cfg);
    ($base->getFeatures() & EventConfig::FEATURE_FDS)
        and print "FDS - arbitrary file descriptor types, and not just sockets\n";
}
/* }}} */

/* {{{ Base */
$base = new EventBase();
$event = new Event($base, STDIN, Event::READ | Event::PERSIST, function ($fd, $events, $arg) {
    static $max_iterations = 0;

    if (++$max_iterations >= 5) {
        /* exit after 5 iterations with timeout of 2.33 seconds */
        echo "Stopping...\n";
        $arg[0]->exit(2.33);
    }

    echo fgets($fd);
}, array (&$base));

$event->add();
$base->loop();
/* Base }}} */
?>

Example #8 Simple HTTP server

<?php
/*
 * Simple HTTP server.
 *
 * To test it:
 * 1) Run it on a port of your choice, e.g.:
 * $ php examples/http.php 8010
 * 2) In another terminal connect to some address on this port
 * and make GET or POST request(others are turned off here), e.g.:
 * $ nc -t 127.0.0.1 8010
 * POST /about HTTP/1.0
 * Content-Type: text/plain
 * Content-Length: 4
 * Connection: close
 * (press Enter)
 *
 * It will output
 * a=12
 * HTTP/1.0 200 OK
 * Content-Type: text/html; charset=ISO-8859-1
 * Connection: close
 *
 * $ nc -t 127.0.0.1 8010
 * GET /dump HTTP/1.0
 * Content-Type: text/plain
 * Content-Encoding: UTF-8
 * Connection: close
 * (press Enter)
 *
 * It will output:
 * HTTP/1.0 200 OK
 * Content-Type: text/html; charset=ISO-8859-1
 * Connection: close
 * (press Enter)
 *
 * $ nc -t 127.0.0.1 8010
 * GET /unknown HTTP/1.0
 * Connection: close
 *
 * It will output:
 * HTTP/1.0 200 OK
 * Content-Type: text/html; charset=ISO-8859-1
 * Connection: close
 *
 * 3) See what the server outputs on the previous terminal window.
 */

function _http_dump($req, $data) {
    static $counter      = 0;
    static $max_requests = 2;

    if (++$counter >= $max_requests)  {
        echo "Counter reached max requests $max_requests. Exiting\n";
        exit();
    }

    echo __METHOD__, " called\n";
    echo "request:"; var_dump($req);
    echo "data:"; var_dump($data);

    echo "\n===== DUMP =====\n";
    echo "Command:", $req->getCommand(), PHP_EOL;
    echo "URI:", $req->getUri(), PHP_EOL;
    echo "Input headers:"; var_dump($req->getInputHeaders());
    echo "Output headers:"; var_dump($req->getOutputHeaders());

    echo "\n >> Sending reply ...";
    $req->sendReply(200, "OK");
    echo "OK\n";

    echo "\n >> Reading input buffer ...\n";
    $buf = $req->getInputBuffer();
    while ($s = $buf->readLine(EventBuffer::EOL_ANY)) {
        echo $s, PHP_EOL;
    }
    echo "No more data in the buffer\n";
}

function _http_about($req) {
    echo __METHOD__, PHP_EOL;
    echo "URI: ", $req->getUri(), PHP_EOL;
    echo "\n >> Sending reply ...";
    $req->sendReply(200, "OK");
    echo "OK\n";
}

function _http_default($req, $data) {
    echo __METHOD__, PHP_EOL;
    echo "URI: ", $req->getUri(), PHP_EOL;
    echo "\n >> Sending reply ...";
    $req->sendReply(200, "OK");
    echo "OK\n";
}

$port = 8010;
if ($argc > 1) {
    $port = (int) $argv[1];
}
if ($port <= 0 || $port > 65535) {
    exit("Invalid port");
}

$base = new EventBase();
$http = new EventHttp($base);
$http->setAllowedMethods(EventHttpRequest::CMD_GET | EventHttpRequest::CMD_POST);

$http->setCallback("/dump", "_http_dump", array(4, 8));
$http->setCallback("/about", "_http_about");
$http->setDefaultCallback("_http_default", "custom data value");

$http->bind("0.0.0.0", 8010);
$base->loop();
?>

The above example will output something similar to:

a=12
HTTP/1.0 200 OK
Content-Type: text/html; charset=ISO-8859-1
Connection: close

HTTP/1.0 200 OK
Content-Type: text/html; charset=ISO-8859-1
Connection: close
(press Enter)

HTTP/1.0 200 OK
Content-Type: text/html; charset=ISO-8859-1
Connection: close

Example #9 Simple HTTPS server

<?php
/*
 * Simple HTTPS server.
 *
 * 1) Run the server: `php examples/https.php 9999`
 * 2) Test it: `php examples/ssl-connection.php 9999`
 */

function _http_dump($req, $data) {
    static $counter      = 0;
    static $max_requests = 200;

    if (++$counter >= $max_requests)  {
        echo "Counter reached max requests $max_requests. Exiting\n";
        exit();
    }

    echo __METHOD__, " called\n";
    echo "request:"; var_dump($req);
    echo "data:"; var_dump($data);

    echo "\n===== DUMP =====\n";
    echo "Command:", $req->getCommand(), PHP_EOL;
    echo "URI:", $req->getUri(), PHP_EOL;
    echo "Input headers:"; var_dump($req->getInputHeaders());
    echo "Output headers:"; var_dump($req->getOutputHeaders());

    echo "\n >> Sending reply ...";
    $req->sendReply(200, "OK");
    echo "OK\n";

    $buf = $req->getInputBuffer();
    echo "\n >> Reading input buffer (", $buf->length, ") ...\n";
    while ($s = $buf->read(1024)) {
        echo $s;
    }
    echo "\nNo more data in the buffer\n";
}

function _http_about($req) {
    echo __METHOD__, PHP_EOL;
    echo "URI: ", $req->getUri(), PHP_EOL;
    echo "\n >> Sending reply ...";
    $req->sendReply(200, "OK");
    echo "OK\n";
}

function _http_default($req, $data) {
    echo __METHOD__, PHP_EOL;
    echo "URI: ", $req->getUri(), PHP_EOL;
    echo "\n >> Sending reply ...";
    $req->sendReply(200, "OK");
    echo "OK\n";
}

function _http_400($req) {
    $req->sendError(400);
}

function _init_ssl() {
    $local_cert = __DIR__."/ssl-echo-server/cert.pem";
    $local_pk   = __DIR__."/ssl-echo-server/privkey.pem";

    $ctx = new EventSslContext(EventSslContext::SSLv3_SERVER_METHOD, array (
        EventSslContext::OPT_LOCAL_CERT  => $local_cert,
        EventSslContext::OPT_LOCAL_PK    => $local_pk,
        //EventSslContext::OPT_PASSPHRASE  => "test",
        EventSslContext::OPT_ALLOW_SELF_SIGNED => true,
    ));

    return $ctx;
}

$port = 9999;
if ($argc > 1) {
    $port = (int) $argv[1];
}
if ($port <= 0 || $port > 65535) {
    exit("Invalid port");
}
$ip = '0.0.0.0';

$base = new EventBase();
$ctx  = _init_ssl();
$http = new EventHttp($base, $ctx);
$http->setAllowedMethods(EventHttpRequest::CMD_GET | EventHttpRequest::CMD_POST);

$http->setCallback("/dump", "_http_dump", array(4, 8));
$http->setCallback("/about", "_http_about");
$http->setCallback("/err400", "_http_400");
$http->setDefaultCallback("_http_default", "custom data value");

$http->bind($ip, $port);
$base->dispatch();

Example #10 OpenSSL connection

<?php
/*
 * Sample OpenSSL client.
 *
 * Usage:
 * 1) Launch a server, e.g.:
 * $ php examples/https.php 9999
 *
 * 2) Launch the client in another terminal:
 * $ php examples/ssl-connection.php 9999
 */

function _request_handler($req, $base) {
    echo __FUNCTION__, PHP_EOL;

    if (is_null($req)) {
        echo "Timed out\n";
    } else {
        $response_code = $req->getResponseCode();

        if ($response_code == 0) {
            echo "Connection refused\n";
        } elseif ($response_code != 200) {
            echo "Unexpected response: $response_code\n";
        } else {
            echo "Success: $response_code\n";
            $buf = $req->getInputBuffer();
            echo "Body:\n";
            while ($s = $buf->readLine(EventBuffer::EOL_ANY)) {
                echo $s, PHP_EOL;
            }
        }
    }

    $base->exit(NULL);
}

function _init_ssl() {
    $ctx = new EventSslContext(EventSslContext::SSLv3_CLIENT_METHOD, array ());

    return $ctx;
}


// Allow to override the port
$port = 9999;
if ($argc > 1) {
    $port = (int) $argv[1];
}
if ($port <= 0 || $port > 65535) {
    exit("Invalid port\n");
}
$host = '127.0.0.1';

$ctx = _init_ssl();
if (!$ctx) {
    trigger_error("Failed creating SSL context", E_USER_ERROR);
}

$base = new EventBase();
if (!$base) {
    trigger_error("Failed to initialize event base", E_USER_ERROR);
}

$conn = new EventHttpConnection($base, NULL, $host, $port, $ctx);
$conn->setTimeout(50);

$req = new EventHttpRequest("_request_handler", $base);
$req->addHeader("Host", $host, EventHttpRequest::OUTPUT_HEADER);
$buf = $req->getOutputBuffer();
$buf->add("<html>HTML TEST</html>");
//$req->addHeader("Content-Length", $buf->length, EventHttpRequest::OUTPUT_HEADER);
//$req->addHeader("Connection", "close", EventHttpRequest::OUTPUT_HEADER);
$conn->makeRequest($req, EventHttpRequest::CMD_POST, "/dump");

$base->dispatch();
echo "END\n";
?>

Example #11 EventHttpConnection::makeRequest example

<?php
function _request_handler($req, $base) {
    echo __FUNCTION__, PHP_EOL;

    if (is_null($req)) {
        echo "Timed out\n";
    } else {
        $response_code = $req->getResponseCode();

        if ($response_code == 0) {
            echo "Connection refused\n";
        } elseif ($response_code != 200) {
            echo "Unexpected response: $response_code\n";
        } else {
            echo "Success: $response_code\n";
            $buf = $req->getInputBuffer();
            echo "Body:\n";
            while ($s = $buf->readLine(EventBuffer::EOL_ANY)) {
                echo $s, PHP_EOL;
            }
        }
    }

    $base->exit(NULL);
}

$address = "127.0.0.1";
$port = 80;

$base = new EventBase();
$conn = new EventHttpConnection($base, NULL, $address, $port);
$conn->setTimeout(5);
$req = new EventHttpRequest("_request_handler", $base);

$req->addHeader("Host", $address, EventHttpRequest::OUTPUT_HEADER);
$req->addHeader("Content-Length", "0", EventHttpRequest::OUTPUT_HEADER);
$conn->makeRequest($req, EventHttpRequest::CMD_GET, "/index.cphp");

$base->loop();
?>

The above example will output something similar to:

_request_handler
Success: 200
Body:
PHP, date:
2013-03-13T20:27:52+05:00

Example #12 Connection listener based on a UNIX domain socket

<?php
/*
 * Simple echo server based on libevent's connection listener.
 *
 * Usage:
 * 1) In one terminal window run:
 *
 * $ php unix-domain-listener.php [path-to-socket]
 *
 * 2) In another terminal window open up connection
 * to the socket, e.g.:
 *
 * $ socat - GOPEN:/tmp/1.sock
 *
 * 3) Start typing. The server should repeat the input.
 */

class MyListenerConnection {
    private $bev, $base;

    public function __destruct() {
        if ($this->bev) {
            $this->bev->free();
        }
    }

    public function __construct($base, $fd) {
        $this->base = $base;

        $this->bev = new EventBufferEvent($base, $fd, EventBufferEvent::OPT_CLOSE_ON_FREE);

        $this->bev->setCallbacks(array($this, "echoReadCallback"), NULL,
            array($this, "echoEventCallback"), NULL);

        if (!$this->bev->enable(Event::READ)) {
            echo "Failed to enable READ\n";
            return;
        }
    }

    public function echoReadCallback($bev, $ctx) {
        // Copy all the data from the input buffer to the output buffer
        $bev->output->addBuffer($bev->input);
    }

    public function echoEventCallback($bev, $events, $ctx) {
        if ($events & EventBufferEvent::ERROR) {
            echo "Error from bufferevent\n";
        }

        if ($events & (EventBufferEvent::EOF | EventBufferEvent::ERROR)) {
            $bev->free();
            $bev = NULL;
        }
    }
}

class MyListener {
    public $base,
        $listener,
        $socket;
    private $conn = array();

    public function __destruct() {
        foreach ($this->conn as &$c) $c = NULL;
    }

    public function __construct($sock_path) {
        $this->base = new EventBase();
        if (!$this->base) {
            echo "Couldn't open event base";
            exit(1);
        }

        if (file_exists($sock_path)) {
            unlink($sock_path);
        }

         $this->listener = new EventListener($this->base,
             array($this, "acceptConnCallback"), $this->base,
             EventListener::OPT_CLOSE_ON_FREE | EventListener::OPT_REUSEABLE, -1,
             "unix:$sock_path");

        if (!$this->listener) {
            trigger_error("Couldn't create listener", E_USER_ERROR);
        }

        $this->listener->setErrorCallback(array($this, "accept_error_cb"));
    }

    public function dispatch() {
        $this->base->dispatch();
    }

    // This callback is invoked when there is data to read on $bev
    public function acceptConnCallback($listener, $fd, $address, $ctx) {
        // We got a new connection! Set up a bufferevent for it. */
        $base = $this->base;
        $this->conn[] = new MyListenerConnection($base, $fd);
    }

    public function accept_error_cb($listener, $ctx) {
        $base = $this->base;

        fprintf(STDERR, "Got an error %d (%s) on the listener. "
            ."Shutting down.\n",
            EventUtil::getLastSocketErrno(),
            EventUtil::getLastSocketError());

        $base->exit(NULL);
    }
}

if ($argc <= 1) {
    exit("Socket path is not provided\n");
}
$sock_path = $argv[1];

$l = new MyListener($sock_path);
$l->dispatch();
?>

Example #13 Simple SMTP server

<?php
 /*
 * Author: Andrew Rose <hello at andrewrose dot co dot uk>
 *
 * Usage:
 * 1) Prepare cert.pem certificate and privkey.pem private key files.
 * 2) Launch the server script
 * 3) Open TLS connection, e.g.:
 *      $ openssl s_client -connect localhost:25 -starttls smtp -crlf
 * 4) Start testing the commands listed in `cmd` method below.
 */

class Handler {
    public $domainName = FALSE;
    public $connections = [];
    public $buffers = [];
    public $maxRead = 256000;

    public function __construct() {
        $this->ctx = new EventSslContext(EventSslContext::SSLv3_SERVER_METHOD, [
            EventSslContext::OPT_LOCAL_CERT  => 'cert.pem',
            EventSslContext::OPT_LOCAL_PK    => 'privkey.pem',
            //EventSslContext::OPT_PASSPHRASE  => '',
            EventSslContext::OPT_VERIFY_PEER => false, // change to true with authentic cert
            EventSslContext::OPT_ALLOW_SELF_SIGNED => true // change to false with authentic cert
        ]);

        $this->base = new EventBase();
        if (!$this->base) {
            exit("Couldn't open event base\n");
        }

        if (!$this->listener = new EventListener($this->base,
            [$this, 'ev_accept'],
            $this->ctx,
            EventListener::OPT_CLOSE_ON_FREE | EventListener::OPT_REUSEABLE,
            -1,
            '0.0.0.0:25'))
        {
            exit("Couldn't create listener\n");
        }

        $this->listener->setErrorCallback([$this, 'ev_error']);
        $this->base->dispatch();
    }

    public function ev_accept($listener, $fd, $address, $ctx) {
        static $id = 0;
        $id += 1;

        $this->connections[$id]['clientData'] = '';
        $this->connections[$id]['cnx'] = new EventBufferEvent($this->base, $fd,
            EventBufferEvent::OPT_CLOSE_ON_FREE);

        if (!$this->connections[$id]['cnx']) {
            echo "Failed creating buffer\n";
            $this->base->exit(NULL);
            exit(1);
        }

        $this->connections[$id]['cnx']->setCallbacks([$this, "ev_read"], NULL,
            [$this, 'ev_error'], $id);
        $this->connections[$id]['cnx']->enable(Event::READ | Event::WRITE);

        $this->ev_write($id, '220 '.$this->domainName." wazzzap?\r\n");
    }

    function ev_error($listener, $ctx) {
        $errno = EventUtil::getLastSocketErrno();

        fprintf(STDERR, "Got an error %d (%s) on the listener. Shutting down.\n",
            $errno, EventUtil::getLastSocketError());

        if ($errno != 0) {
            $this->base->exit(NULL);
            exit();
        }
    }

    public function ev_close($id) {
        $this->connections[$id]['cnx']->disable(Event::READ | Event::WRITE);
        unset($this->connections[$id]);
    }

    protected function ev_write($id, $string) {
        echo 'S('.$id.'): '.$string;
        $this->connections[$id]['cnx']->write($string);
    }

    public function ev_read($buffer, $id) {
        while($buffer->input->length > 0) {
            $this->connections[$id]['clientData'] .= $buffer->input->read($this->maxRead);
            $clientDataLen = strlen($this->connections[$id]['clientData']);

            if($this->connections[$id]['clientData'][$clientDataLen-1] == "\n"
                && $this->connections[$id]['clientData'][$clientDataLen-2] == "\r")
            {
                // remove the trailing \r\n
                $line = substr($this->connections[$id]['clientData'], 0,
                    strlen($this->connections[$id]['clientData']) - 2);

                $this->connections[$id]['clientData'] = '';
                $this->cmd($buffer, $id, $line);
            }
        }
    }

    protected function cmd($buffer, $id, $line) {
        switch ($line) {
            case strncmp('EHLO ', $line, 4):
                $this->ev_write($id, "250-STARTTLS\r\n");
                $this->ev_write($id, "250 OK ehlo\r\n");
                break;

            case strncmp('HELO ', $line, 4):
                $this->ev_write($id, "250-STARTTLS\r\n");
                $this->ev_write($id, "250 OK helo\r\n");
                break;

            case strncmp('QUIT', $line, 3):
                $this->ev_write($id, "250 OK quit\r\n");
                $this->ev_close($id);
                break;

            case strncmp('STARTTLS', $line, 3):
                $this->ev_write($id, "220 Ready to start TLS\r\n");
                $this->connections[$id]['cnx'] = EventBufferEvent::sslFilter($this->base,
                    $this->connections[$id]['cnx'], $this->ctx,
                    EventBufferEvent::SSL_ACCEPTING,
                    EventBufferEvent::OPT_CLOSE_ON_FREE);
                $this->connections[$id]['cnx']->setCallbacks([$this, "ev_read"], NULL, [$this, 'ev_error'], $id);
                $this->connections[$id]['cnx']->enable(Event::READ | Event::WRITE);
                break;

            default:
                echo 'unknown command: '.$line."\n";
                break;
        }
    }
}

new Handler();