@Override
  public CompletableFuture<List<NatPortMapping>> getPortMappings() {
    return CompletableFuture.completedFuture(forwardedPorts);
  }
Instantiates a new Docker nat manager.

@param ipDetector the ip detector
@param advertisedHost the advertised host
@param p2pPort the p 2 p port
@param rpcHttpPort the rpc http port
nat/src/main/java/org/hyperledger/besu/nat/docker/DockerNatManager.java