deleteResource method

void deleteResource(Object keyExpr, { Timestamp? timestamp, CongestionControl? congestionControl, Priority? priority, bool? isExpress, Locality? allowedDestination, })

Deletes a resource on the given keyExpr.

An optional timestamp can be attached to the message; borrowed, not consumed.

Send options

congestionControl, priority, isExpress and allowedDestination are each optional, and omitting one — or passing null — means the same thing: canon decides. This binding substitutes no value of its own. On this path canon's defaults are CongestionControl.drop (a push operation; get and declareQuerier default to CongestionControl.block instead), Priority.data, isExpress: false, and Locality.any.

⚠️ Read CongestionControl before selecting CongestionControl.block: it can park the calling thread for seconds and then close the transport.

Throws ZenohException if the key expression is invalid or the delete fails. Throws StateError if the session has been closed.

⛔ Throws ArgumentError if congestionControl is CongestionControl.blockFirst and the loaded native was built without Z_FEATURE_UNSTABLE_API. canon declares Z_CONGESTION_CONTROL_BLOCK_FIRST only under that flag, so on such a build there is no value to send. Pass CongestionControl.block or CongestionControl.drop, or select the unstable native through your app's user_defines.

Implementation

void deleteResource(
  Object keyExpr, {
  Timestamp? timestamp,
  CongestionControl? congestionControl,
  Priority? priority,
  bool? isExpress,
  Locality? allowedDestination,
}) {
  // FIRST STATEMENT: ahead of the timestamp allocation and the key
  // expression's validation.
  requireCongestionControlSupported(congestionControl);
  final tsPtr = timestamp != null ? _timestampToNative(timestamp) : nullptr;
  try {
    _withKeyExprArg<void>(keyExpr, 'keyExpr', (loanedSession, loanedKe) {
      final rc = bindings.zd_delete(
        loanedSession.cast(),
        loanedKe.cast(),
        tsPtr.cast(),
        congestionControl?.value ?? -1,
        priority?.value ?? -1,
        isExpress == null ? -1 : (isExpress ? 1 : 0),
        allowedDestination?.value ?? -1,
      );
      if (rc != 0) {
        throw ZenohException('Delete failed', rc);
      }
    });
  } finally {
    if (tsPtr != nullptr) calloc.free(tsPtr);
  }
}