/** * 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; }); }