/**
* Creates a `Promise` which resolves with an array of all the event data
*
* @param ReadableStreamInterface|WritableStreamInterface $stream
* @param string $event
* @return CancellablePromiseInterface Promise<string, Exception>
*/
function all(EventEmitterInterface $stream, $event = 'data')
{
// stream already ended => resolve with empty buffer
if ($stream instanceof ReadableStreamInterface) {
// readable or duplex stream not readable => already closed
// a half-open duplex stream is considered closed if its readable side is closed
if (!$stream->isReadable()) {
return Promise\resolve(array());
}
} elseif ($stream instanceof WritableStreamInterface) {
// writable-only stream (not duplex) not writable => already closed
if (!$stream->isWritable()) {
return Promise\resolve(array());
}
}
$buffer = array();
$bufferer = function ($data) use(&$buffer) {
$buffer[] = $data;
};
$stream->on($event, $bufferer);
$promise = new Promise\Promise(function ($resolve, $reject) use($stream, &$buffer) {
$stream->on('error', function ($error) use($reject) {
$reject(new \RuntimeException('An error occured on the underlying stream while buffering', 0, $error));
});
$stream->on('close', function () use($resolve, &$buffer) {
$resolve($buffer);
});
}, function ($_, $reject) {
$reject(new \RuntimeException('Cancelled buffering'));
});
return $promise->then(null, function ($error) use(&$buffer, $bufferer, $stream, $event) {
// promise rejected => clear buffer and buffering
$buffer = array();
$stream->removeListener($event, $bufferer);
throw $error;
});
}
