Method _unreserve

src/master/http.cpp:4132–4166

Future<Response> Master::Http::_unreserve(
    const SlaveID& slaveId,
    const RepeatedPtrField<Resource>& resources,
    const Option<Principal>& principal) const
{
  Slave* slave = master->slaves.registered.get(slaveId);
  if (slave == nullptr) {
    return BadRequest("No agent found with specified ID");
  }

  // Create an operation.
  Offer::Operation operation;
  operation.set_type(Offer::Operation::UNRESERVE);
  operation.mutable_unreserve()->mutable_resources()->CopyFrom(resources);

  Option<Error> error = validateAndUpgradeResources(&operation);
  if (error.isSome()) {
    return BadRequest(error->message);
  }

  error = validation::operation::validate(operation.unreserve());
  if (error.isSome()) {
    return BadRequest("Invalid UNRESERVE operation: " + error->message);
  }

  return master->authorize(
      principal, ActionObject::unreserve(operation.unreserve()))
    .then(defer(master->self(), [=](bool authorized) -> Future<Response> {
      if (!authorized) {
        return Forbidden();
      }

      return _operation(slaveId, operation);
    }));
}


Future<Response> Master::Http::_operation(