/**
* Creates a `Promise` which resolves with the stream data buffer
*
* @param ReadableStreamInterface $stream
* @return CancellablePromiseInterface Promise<string, Exception>
*/
function buffer(ReadableStreamInterface $stream)
{
// stream already ended => resolve with empty buffer
if (!$stream->isReadable()) {
return Promise\resolve('');
}
$buffer = '';
$bufferer = function ($data) use(&$buffer) {
$buffer .= $data;
};
$stream->on('data', $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) {
// promise rejected => clear buffer and buffering
$buffer = '';
$stream->removeListener('data', $bufferer);
throw $error;
});
}
/**
* Removes all given listeners from the stream
*
* @param Stream $stream
* @param array &$listeners
*/
function _remove_listeners(Stream $stream, array $listeners)
{
foreach ($listeners as $event => $callable) {
$stream->removeListener($event, $callable);
}
}
