There is no way to reject receiving binary data / stream or terminate it

[andres-kovalev]

As mentioned in the title - there is no way:

• to reject receiving an action payload (for instance, peer might want to reject huge blobs)
• cancel any ongoing action transmission (for instance, peer might want to cancel ongoing file transmission if it's too big or sent by mistake)

Is it by design?

P.S. The first issue can be solved by additional pair of actions to perform a handshake:

const [sendFile, onFileReceived] = room.makeAction('file');
const [ask, onRequest] = room.makeAction('request');
const [respond, onResponse] = room.makeAction('response');

onRequest((request, peerId) => {
  const shouldReject = banned.has(peerId) || request.size > MAX_SIZE;

  respond({ reqId: request.id, result: shouldReject ? 'reject' : 'accept' }, peerId);
});

onResponse((response, peerId) => {
  if (response.result === 'accept') sendFile(requestsMap[response.reqId].file, peerId);
  else if (response.result === 'reject') requestsMap.delete(response.reqId);
});