how I (ab)used PHP with the help of reactphp 

Stijn Vannieuwenhuyse head of engineering at teamleader 

Stijn Vannieuwenhuyse track and field timer 

Track & Field it's all about precise numbers 

Team Arctic v.z.w. team for athletics' results communication, timing, information and coordination 

Track & Field it's all about precise numbers 

No content

What's wrong with it? Why change? 

Problem 1 How to integrate? 

FT01 Long jump men Lambert Romain DAMP A6 Rank: 1 

RS232 

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Problem 2 How to connect? 

PHP developer 

reactphp event-driven, non-blocking I/O with PHP 

public function run() { $this->running = true; while ($this->running) { $this->nextTickQueue->tick(); $this->futureTickQueue->tick(); $this->timers->tick(); if (!$this->running || !$this->nextTickQueue->isEmpty() || !$this->futureTickQueue->isEmpty()) { $timeout = 0; } elseif ($scheduledAt = $this->timers->getFirst()) { $timeout = $scheduledAt - $this->timers->getTime(); if ($timeout < 0) { $timeout = 0; } else { $timeout *= self::MICROSECONDS_PER_SECOND; } } elseif ($this->readStreams || $this->writeStreams) { $timeout = null; } else { break; } $this->waitForStreamActivity($timeout); } } 

composer require react/react 

Problem 2 How to connect? 

$loop = LoopFactory::create(); $connector = new TcpConnector($loop); $connector->create('192.168.1.93', 6000)->then( function(Stream $stream) { echo "connected", PHP_EOL; } ); $loop->run(); 

composer require react/socket-client 

Problem 3 How to communicate? 

C\x0d 

TFF000000a2000700100030a012345678910\x0d 

TFF000000a2000700100030a012345678910\x0d TRRGGBBXXXXYYYYLLLLHHHHFDDDDDDDDDDDD\x0d T: command name RRGGBB: hex color value XXXX: x-position in hex, starting from left YYYY: y-position in hex, starting from top LLLL: length of the text in hex HHHH: heigth of the text in hex F: font-type D: data \x0d: end marker 

Domain Driven Design make the implicit explicit 

interface Instruction { /** * @return string */ public function toData(); } 

class Clear implements Instruction { public function toData() { return "C\x0d"; } } 

class Text implements Instruction { private $data; private $x; private $y; private $height; private $length; private $colorCode; private $font; public function __construct($data, $x, $y, $height, $length, $colorCode, $font) { $this->data = $data; $this->x = $x; $this->y = $y; $this->height = $height; $this->length = $length; $this->colorCode = $colorCode; $this->font = $font; } public function toData() { return sprintf( "T%s%04X%04X%04X%04X%s%s\x0d", $this->getColor(), //returns hex string of red, green or yellow $this->x, $this->y, $this->length, $this->height, $this->font, $this->data ); } } 

B00100028004700af0f0f0f0fff0fff0f\x0d 

BXXXXYYYYLLLLHHHHDDDDDDDDDDD\x0d B: command name XXXX: x-position in hex, starting from left YYYY: y-position in hex, starting from top LLLL: length of the text in hex HHHH: heigth of the text in hex D: data \x0d: end marker 

Domain Specific Language 

. . . . . . . . . . . Y Y Y Y Y Y Y . . . . . . . . . . . . . . . . . . . Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y R R R R R R R R R R R Y . . . . . Y G G G G G G G G G G G G G G G G G G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . . . . Y . Y Y Y . Y . . . . . G . . . . . G . . . . . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . R . R R R . Y . . . Y . Y . G . G . G . G G G . G . G G G . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . R . . . R . Y . Y Y Y . Y . G . G . G . G . . . G . G . . . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . R . R R R . Y . . . Y . Y . G G G . G . G G G . G . G G G . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . R . R . . . Y . Y Y Y . Y . . . G . G . . . G . G . G . G . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . R . R R R . Y . . . . . Y . . . G . G . G G G . G . G G G . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R . . . . . Y . . . . . Y . . . . . G . . . . . G . . . . . G . Y . . . . . . . . . . . . . . . . . . . . . . . . . . Y Y Y Y Y Y Y Y Y Y Y Y . . . . . Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . . . . . . . . . . . . . . . . . . . 

Value Objects 

new Bitmap() new BitmapBlock() new BitmapLine() 

Dot Matrix Fonts 

final class AdvancedDotDigital extends Font { protected static $chars = [ "0" => "01111110\n11111111\n11000011\n11000011\n11000011\n11000011\n11000011\n11000011\n11000011\n11000011\n11111111\n01111110", "1" => "00011000\n00111000\n01111000\n11011000\n00011000\n00011000\n00011000\n00011000\n00011000\n00011000\n11111111\n11111111", "2" => "01111110\n11111111\n11000011\n00000011\n00000011\n01111111\n11111110\n11000000\n11000000\n11000000\n11111111\n11111111", "3" => "01111110\n11111111\n11000011\n00000011\n00000011\n00111110\n00111110\n00000011\n00000011\n11000011\n11111111\n01111110", "4" => "11000011\n11000011\n11000011\n11000011\n11000011\n11000011\n11111111\n11111111\n00000011\n00000011\n00000011\n00000011", "5" => "11111111\n11111111\n11000000\n11000000\n11111110\n11111111\n00000011\n00000011\n00000011\n11000011\n11111111\n01111110", "6" => "01111110\n11111111\n11000011\n11000000\n11111110\n11111111\n11000011\n11000011\n11000011\n11000011\n11111111\n01111110", "7" => "11111111\n11111111\n11000110\n00000110\n00001100\n00001100\n00011000\n00011000\n00110000\n00110000\n00110000\n00110000", "8" => "01111110\n11111111\n11000011\n11000011\n11000011\n01111110\n01111110\n11000011\n11000011\n11000011\n11111111\n01111110", "9" => "01111110\n11111111\n11000011\n11000011\n11000011\n11000011\n11111111\n01111111\n00000011\n11000011\n11111111\n01111110", "m" => "0000000000\n0000000000\n0000000000\n0000000000\n0000000000\n1111101110\n1111111111\n1100110011\n1100110011\n1100110011\n1100110011\n1100110011\n1100110011", "X" => "1100000000011\n0110000000110\n0011000001100\n0001100011000\n0000110110000\n0000011100000\n0000011100000\n0000110110000\n0001100011000\n0011000001100\n0110000000110\n1100000000011", "O" => "0000111110000\n0011111111100\n0111000001110\n0110000000110\n1100000000011\n1100000000011\n1100000000011\n1100000000011\n0110000000110\n0111000001110\n0011111111100\n0000111110000", ":" => "0000\n0000\n0110\n0110\n0000\n0000\n0000\n0000\n0110\n0110\n0000\n0000", "-" => "0000000000000\n0000000000000\n0000000000000\n0000000000000\n0000000000000\n0011111111100\n0011111111100\n0000000000000\n0000000000000\n0000000000000\n0000000000000\n0000000000000", ]; } 

Problem 4 How to get updates? 

inotify 

inotify_init() : filedescriptor inotify_add_watch($fd, $path, $mask) : watchDescriptorId inotify_rm_watch($fd, $wdId) inotify_read($fd) : event[] IN_MODIFY IN_CREATE IN_ALL_EVENTS IN_OPEN ... 

class Watcher { public function __construct($dir, LoopInterface $loop) { $fd = inotify_init(); stream_set_blocking(fd, 0); inotify_add_watch($fd, $dir, IN_MODIFY); $loop->addReadStream($fd, function($fd) { foreach(inotify_read($fd) as $events) { //process change } } ) } } 

Problem 5 How to combine I/O? 

interface Layout { /** * @return Instruction[] */ public function toInstructions(); } 

class NextAthlete implements Layout { private $name; private $team; private $attempt; private $place = null; private $height = null; public function __construct($name, $team, $attempt, $place = null, $height = null) { $this->name = $name; $this->team = $team; $this->attempt = $attempt; $this->place = $place; $this->height = $height; } /** * @return Instruction[] */ public function toInstructions() { $instructions = []; $name = (new Text(strtoupper($this->name), RingMatrix::class, "Y"))->toBitmap(); $instructions[] = new Bitmap(0, 0, $name); $team = (new Text(strtoupper($this->team), SquareDotDigital::class, "R"))->toBitmap(); $instructions[] = new Bitmap(64 - $team->getLength(), 11, $team); //some other conversion from data to instructions return $instructions; } } 

Problem 6 How to send own layouts? 

PHP TCP server 

$loop = Factory::create(); $server = new Server($loop); $server->on('connection', function (Connection $connection) { echo sprintf("%s came online\n", $connection->getRemoteAddress()); $connection->on('close', function(Stream $stream) use ($connection) { echo sprintf("%s went offline\n", $connection->getRemoteAddress()); }); }); $server->listen('6000', '0.0.0.0'); $loop->run(); 

Command pattern 

{ "commandName":"Nortuni.FieldScoreboardManager.Commands.ShowLayout", "payload": { "scoreBoardId": "LED01", "layoutName": "TwoLines", "data": { "line1": "TEAM", "line2": "ARCTIC" } } } 

$loop = Factory::create(); $deviceServer = new Server($loop); $commandServer = new Server($loop); $deviceServer->on('connection', function (Connection $connection) { //do some stuff }); $commandServer->on('connection', function (Connection $connection) { $connection->on('data', function() { //parse json to command //dispatch command }) }); $deviceServer->listen('6000', '0.0.0.0'); $commandServer->listen('6001', '0.0.0.0'); $loop->run(); 

Problem 7 How to open up control? 

$socketServer = new Server($loop); $webserver = new React\Http\Server($socketServer); $webserver->on('request', function ($request, $response) { //just like a normal controller method //$response is a writable stream }); $socket->listen(8080); 

Problem 8 How to get current state? 

websockets 

composer require cboden/ratchet 

class WebSocketConnector implements MessageComponentInterface { private $clients; public function __construct() { $this->clients = new SplObjectStorage; } public function onOpen(ConnectionInterface $connection) { $this->clients->attach($conn); } public function onClose(ConnectionInterface $connection) { $this->clients->detach($connection); } public function onError(ConnectionInterface $connection, \Exception $e) { $connection->close(); } public function onMessage(ConnectionInterface $from, $msg) { //process data } public function sendToClients($data) { foreach($this->clients as $client) { $client->send($data); } } } 

$socketServer = new Ratchet\App('192.168.15.100', 8080, '0.0.0.0', $loop); $socketServer->route('/field', new WebSocketConnector(), ['*']); 

var connection = null; var connect = function() { connection = new WebSocket('ws://192.168.15.100:8080/field'); connection.onopen = function() { //log or ... }; connection.onmessage = function(message) { //process message.data } connection.onclose = function() { connection = null; setTimeout(connect, 1000); }; } var dispatch = function(data) { if(connection && connection.readyState == WebSocket.OPEN) { connection.send(data); } }; 

Problem 9 How to automate? 

{ "commandName":"Nortuni.FieldScoreboardManager.Commands.ShowSlideshow", "payload": { "scoreBoardId":"LED01", "interval":"20", "screens":[ { "layoutName":"MeetingName", "data": { "line1":"PHPGENT", "line2":"MEETUP", "line3":"", "line4":"WELCOME" } }, { "layoutName":"MeetingName", "data": { "line1":"", "line2":"TEAMLEADER", "line3":"CRM", "line4":"" } } ] } } 

timers 

$this->timer = $this->loop->addPeriodicTimer($interval, function() { $this->showNextSlide(); }); 

it works for now 

my experiences 

async programming in PHP is possible 

php is stable enough for long running processes 

reactphp is a mature and rich library 

I use reactphp in production 

I shouldn't use php for this 

Questions? 

sponsorship [email protected] 

Stijn Vannieuwenhuyse @stijnvnh https://joind.in/talk/822f4