Compression is incompatible with streaming responses #324
Description
I tried to make a super-simple SSE server (code below). It was just not working until I disabled the compression. Since I assume streamed responses should work with compression enabled, I open an issue about it.
use Amp\ByteStream\ResourceOutputStream;
use Amp\Http\Server\HttpServer;
use Amp\Http\Server\RequestHandler\CallableRequestHandler;
use Amp\Http\Server\Response;
use Amp\Http\Status;
use Amp\Log\ConsoleFormatter;
use Amp\Log\StreamHandler;
use Amp\Socket;
use Amp\Http\Server\Request;
use Monolog\Logger;
use Amp\ByteStream\IteratorStream;
use Amp\Producer;
function newEvent() {
$id = mt_rand(1, 1000);
return ['id' => $id, 'title' => 'title ' . $id, 'content' => 'content ' . $id];
}
$events = [
newEvent(),
newEvent(),
];
Amp\Loop::run(static function () use (&$events) {
$cert = new Socket\Certificate(__DIR__ . '/../ssl/cert.pem', __DIR__ . '/../ssl/key.pem');
$context = (new Socket\BindContext)
->withTlsContext((new Socket\ServerTlsContext)->withDefaultCertificate($cert));
$servers = [
Socket\Server::listen("0.0.0.0:1337"),
Socket\Server::listen("[::]:1337"),
Socket\Server::listen("0.0.0.0:1338", $context),
Socket\Server::listen("[::]:1338", $context),
];
$logHandler = new StreamHandler(new ResourceOutputStream(STDOUT));
$logHandler->setFormatter(new ConsoleFormatter);
$logger = new Logger('server');
$logger->pushHandler($logHandler);
$server = new HttpServer($servers, new CallableRequestHandler(static function (Request $request) use (&$events) {
if ($request->getUri()->getPath() === '/') {
return new Response(
Status::OK,
[
"content-type" => "text/html; charset=utf-8"
],
<<<FRONT
<!DOCTYPE html>
<html lang="en">
<head>
<title>Yo</title>
</head>
<body>
<h1>Hello World!</h1>
<div id="news"></div>
<script>
//*
var news = document.getElementById('news');
const evtSource = new EventSource("/sse");
evtSource.addEventListener('news', function (event) {
news.innerHTML = news.innerHTML + "<p>"+event.data+"</p>";
});
//*/
</script>
</body>
</html>
FRONT
);
}
if ($request->getUri()->getPath() === '/sse') {
return new Response(
Status::OK,
[
'Access-Control-Allow-Origin' => '*',
'Content-Type' => 'text/event-stream',
'Cache-Control' => 'no-cache',
'X-Accel-Buffering' => 'no'
],
new IteratorStream(new Producer(function (callable $emit) use (&$events) {
while(true) {
if (empty($events)) {
yield new \Amp\Delayed(10);
} else {
$data = json_encode(array_pop($events));
yield $emit(
"event: news\ndata: $data\n\n"
);
}
}
}
))
);
}
return new Response(Status::NOT_FOUND, ["content-type" => "text/plain; charset=utf-8"], '404 Not found');
// uncomment the option part to make it work
}), $logger/*, (new \Amp\Http\Server\Options())->withoutCompression()*/);
yield $server->start();
// Stop the server when SIGINT is received (this is technically optional, but it is best to call Server::stop()).
Amp\Loop::onSignal(\SIGINT, static function (string $watcherId) use ($server) {
Amp\Loop::cancel($watcherId);
yield $server->stop();
});
});Using this works:
$server = new HttpServer($servers, stack(new CallableRequestHandler(static function (Request $request) use (&$events) {
// ...
}), new \Amp\Http\Server\Middleware\CompressionMiddleware(12, 1));
// Note: 12 is minimum data for an sse.