How to determine the number of nodes in a Redshift cluster?

Question

I need to programmatically determine the number of nodes in a Redshift cluster. I was hoping the AWS Java APIs would provide it in a cluster description, but I am not able to locate it. Can anyone point me in the right direction?

Answer 1

Yes, it is possible, via DescribeCluster. Each cluster within the region passed to the client is listed as a Cluster item, which has a NumberOfNodes attribute. For instance:

final AmazonRedshiftClient client = new AmazonRedshiftClient(credentials).withRegion(com.amazonaws.regions.Regions.US_WEST_2);
final DescribeClustersResult describeResult = client.describeClusters();
describeResult.getClusters()
              .stream()
              .forEach(cluster -> System.out.println(String.format("Cluster: %s \nNumber of nodes: %d",
                                                                   cluster.getClusterIdentifier(),
                                                                   cluster.getNumberOfNodes())));

Gives me:

Cluster: cluster-22gsextori36
Number of nodes: 1
Cluster: cluster-22gsextori38 
Number of nodes: 1
Cluster: cluster-22gsextori40 
Number of nodes: 1