Usar o AWS SDK para configurar o Auto Scaling em tabelas do Amazon DynamoDB - Amazon DynamoDB
Habilitação do Application Auto Scaling para uma tabelaDesabilitar o Application Auto Scaling para uma tabela

Usar o AWS SDK para configurar o Auto Scaling em tabelas do Amazon DynamoDB

Além de usar o AWS Management Console e a AWS Command Line Interface (AWS CLI), você pode escrever aplicações que interagem com o Auto Scaling do Amazon DynamoDB. Esta seção contém dois programas Java que podem ser usados para testar essa funcionalidade:

  • EnableDynamoDBAutoscaling.java

  • DisableDynamoDBAutoscaling.java

Habilitação do Application Auto Scaling para uma tabela

O programa a seguir mostra um exemplo de configuração de uma política de Auto Scaling para uma tabela do DynamoDB (TestTable). Ele procede da seguinte maneira:

  • O programa registra unidades de capacidade de gravação como um destino dimensionável para a TestTable. O intervalo dessa métrica é entre 5 e 10 unidades de capacidade de gravação.

  • Depois que o destino escalável é criado, o programa cria uma configuração de rastreamento de destino. A política procura manter uma taxa de destino de 50% entre a capacidade de gravação consumida e a capacidade de gravação provisionada.

  • Em seguida, o programa cria a política de escalabilidade com base na configuração de rastreamento de destino.

nota

Ao remover manualmente uma tabela ou uma réplica de tabela global, você não remove automaticamente os destinos escaláveis associados, políticas de escalabilidade nem alarmes do CloudWatch.

Java v2
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.applicationautoscaling.ApplicationAutoScalingClient;
import software.amazon.awssdk.services.applicationautoscaling.model.ApplicationAutoScalingException;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalableTargetsRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalableTargetsResponse;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalingPoliciesRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalingPoliciesResponse;
import software.amazon.awssdk.services.applicationautoscaling.model.PolicyType;
import software.amazon.awssdk.services.applicationautoscaling.model.PredefinedMetricSpecification;
import software.amazon.awssdk.services.applicationautoscaling.model.PutScalingPolicyRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.RegisterScalableTargetRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.ScalingPolicy;
import software.amazon.awssdk.services.applicationautoscaling.model.ServiceNamespace;
import software.amazon.awssdk.services.applicationautoscaling.model.ScalableDimension;
import software.amazon.awssdk.services.applicationautoscaling.model.MetricType;
import software.amazon.awssdk.services.applicationautoscaling.model.TargetTrackingScalingPolicyConfiguration;
import java.util.List;

/**
 * Before running this Java V2 code example, set up your development environment, including your credentials.
 *
 * For more information, see the following documentation topic:
 *
 * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 */
public class EnableDynamoDBAutoscaling {
    public static void main(String[] args) {
        final String usage = """

            Usage:
               <tableId> <roleARN> <policyName>\s

            Where:
               tableId - The table Id value (for example, table/Music).
               roleARN - The ARN of the role that has ApplicationAutoScaling permissions.
               policyName - The name of the policy to create.
               
            """;

        if (args.length != 3) {
            System.out.println(usage);
            System.exit(1);
        }

        System.out.println("This example registers an Amazon DynamoDB table, which is the resource to scale.");
        String tableId = args[0];
        String roleARN = args[1];
        String policyName = args[2];
        ServiceNamespace ns = ServiceNamespace.DYNAMODB;
        ScalableDimension tableWCUs = ScalableDimension.DYNAMODB_TABLE_WRITE_CAPACITY_UNITS;
        ApplicationAutoScalingClient appAutoScalingClient = ApplicationAutoScalingClient.builder()
            .region(Region.US_EAST_1)
            .build();

        registerScalableTarget(appAutoScalingClient, tableId, roleARN, ns, tableWCUs);
        verifyTarget(appAutoScalingClient, tableId, ns, tableWCUs);
        configureScalingPolicy(appAutoScalingClient, tableId, ns, tableWCUs, policyName);
    }

    public static void registerScalableTarget(ApplicationAutoScalingClient appAutoScalingClient, String tableId, String roleARN, ServiceNamespace ns, ScalableDimension tableWCUs) {
        try {
            RegisterScalableTargetRequest targetRequest = RegisterScalableTargetRequest.builder()
                .serviceNamespace(ns)
                .scalableDimension(tableWCUs)
                .resourceId(tableId)
                .roleARN(roleARN)
                .minCapacity(5)
                .maxCapacity(10)
                .build();

            appAutoScalingClient.registerScalableTarget(targetRequest);
            System.out.println("You have registered " + tableId);

        } catch (ApplicationAutoScalingException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
        }
    }

    // Verify that the target was created.
    public static void verifyTarget(ApplicationAutoScalingClient appAutoScalingClient, String tableId, ServiceNamespace ns, ScalableDimension tableWCUs) {
        DescribeScalableTargetsRequest dscRequest = DescribeScalableTargetsRequest.builder()
            .scalableDimension(tableWCUs)
            .serviceNamespace(ns)
            .resourceIds(tableId)
            .build();

        DescribeScalableTargetsResponse response = appAutoScalingClient.describeScalableTargets(dscRequest);
        System.out.println("DescribeScalableTargets result: ");
        System.out.println(response);
    }

    // Configure a scaling policy.
    public static void configureScalingPolicy(ApplicationAutoScalingClient appAutoScalingClient, String tableId, ServiceNamespace ns, ScalableDimension tableWCUs, String policyName) {
        // Check if the policy exists before creating a new one.
        DescribeScalingPoliciesResponse describeScalingPoliciesResponse = appAutoScalingClient.describeScalingPolicies(DescribeScalingPoliciesRequest.builder()
            .serviceNamespace(ns)
            .resourceId(tableId)
            .scalableDimension(tableWCUs)
            .build());

        if (!describeScalingPoliciesResponse.scalingPolicies().isEmpty()) {
            // If policies exist, consider updating an existing policy instead of creating a new one.
            System.out.println("Policy already exists. Consider updating it instead.");
            List<ScalingPolicy> polList = describeScalingPoliciesResponse.scalingPolicies();
            for (ScalingPolicy pol : polList) {
                System.out.println("Policy name:" +pol.policyName());
            }
        } else {
            // If no policies exist, proceed with creating a new policy.
            PredefinedMetricSpecification specification = PredefinedMetricSpecification.builder()
                .predefinedMetricType(MetricType.DYNAMO_DB_WRITE_CAPACITY_UTILIZATION)
                .build();

            TargetTrackingScalingPolicyConfiguration policyConfiguration = TargetTrackingScalingPolicyConfiguration.builder()
                .predefinedMetricSpecification(specification)
                .targetValue(50.0)
                .scaleInCooldown(60)
                .scaleOutCooldown(60)
                .build();

            PutScalingPolicyRequest putScalingPolicyRequest = PutScalingPolicyRequest.builder()
                .targetTrackingScalingPolicyConfiguration(policyConfiguration)
                .serviceNamespace(ns)
                .scalableDimension(tableWCUs)
                .resourceId(tableId)
                .policyName(policyName)
                .policyType(PolicyType.TARGET_TRACKING_SCALING)
                .build();

            try {
                appAutoScalingClient.putScalingPolicy(putScalingPolicyRequest);
                System.out.println("You have successfully created a scaling policy for an Application Auto Scaling scalable target");
            } catch (ApplicationAutoScalingException e) {
                System.err.println("Error: " + e.awsErrorDetails().errorMessage());
            }
        }
    }
}
Java v1

O programa exige que você forneça um nome do recurso da Amazon (ARN) para uma função vinculada ao serviço Application Auto Scaling válida. (Por exemplo: arn:aws:iam::122517410325:role/AWSServiceRoleForApplicationAutoScaling_DynamoDBTable.) No seguinte programa, substitua SERVICE_ROLE_ARN_GOES_HERE pelo ARN real. 

package com.amazonaws.codesamples.autoscaling;

import com.amazonaws.services.applicationautoscaling.AWSApplicationAutoScalingClient;
import com.amazonaws.services.applicationautoscaling.AWSApplicationAutoScalingClientBuilder;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalableTargetsRequest;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalableTargetsResult;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalingPoliciesRequest;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalingPoliciesResult;
import com.amazonaws.services.applicationautoscaling.model.MetricType;
import com.amazonaws.services.applicationautoscaling.model.PolicyType;
import com.amazonaws.services.applicationautoscaling.model.PredefinedMetricSpecification;
import com.amazonaws.services.applicationautoscaling.model.PutScalingPolicyRequest;
import com.amazonaws.services.applicationautoscaling.model.RegisterScalableTargetRequest;
import com.amazonaws.services.applicationautoscaling.model.ScalableDimension;
import com.amazonaws.services.applicationautoscaling.model.ServiceNamespace;
import com.amazonaws.services.applicationautoscaling.model.TargetTrackingScalingPolicyConfiguration;

public class EnableDynamoDBAutoscaling {

	static AWSApplicationAutoScalingClient aaClient = (AWSApplicationAutoScalingClient) AWSApplicationAutoScalingClientBuilder
			.standard().build();

	public static void main(String args[]) {

		ServiceNamespace ns = ServiceNamespace.Dynamodb;
		ScalableDimension tableWCUs = ScalableDimension.DynamodbTableWriteCapacityUnits;
		String resourceID = "table/TestTable";

		// Define the scalable target
		RegisterScalableTargetRequest rstRequest = new RegisterScalableTargetRequest()
				.withServiceNamespace(ns)
				.withResourceId(resourceID)
				.withScalableDimension(tableWCUs)
				.withMinCapacity(5)
				.withMaxCapacity(10)
				.withRoleARN("SERVICE_ROLE_ARN_GOES_HERE");

		try {
			aaClient.registerScalableTarget(rstRequest);
		} catch (Exception e) {
			System.err.println("Unable to register scalable target: ");
			System.err.println(e.getMessage());
		}

		// Verify that the target was created
		DescribeScalableTargetsRequest dscRequest = new DescribeScalableTargetsRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceIds(resourceID);
		try {
			DescribeScalableTargetsResult dsaResult = aaClient.describeScalableTargets(dscRequest);
			System.out.println("DescribeScalableTargets result: ");
			System.out.println(dsaResult);
			System.out.println();
		} catch (Exception e) {
			System.err.println("Unable to describe scalable target: ");
			System.err.println(e.getMessage());
		}

		System.out.println();

		// Configure a scaling policy
		TargetTrackingScalingPolicyConfiguration targetTrackingScalingPolicyConfiguration = new TargetTrackingScalingPolicyConfiguration()
				.withPredefinedMetricSpecification(
						new PredefinedMetricSpecification()
								.withPredefinedMetricType(MetricType.DynamoDBWriteCapacityUtilization))
				.withTargetValue(50.0)
				.withScaleInCooldown(60)
				.withScaleOutCooldown(60);

		// Create the scaling policy, based on your configuration
		PutScalingPolicyRequest pspRequest = new PutScalingPolicyRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceId(resourceID)
				.withPolicyName("MyScalingPolicy")
				.withPolicyType(PolicyType.TargetTrackingScaling)
				.withTargetTrackingScalingPolicyConfiguration(targetTrackingScalingPolicyConfiguration);

		try {
			aaClient.putScalingPolicy(pspRequest);
		} catch (Exception e) {
			System.err.println("Unable to put scaling policy: ");
			System.err.println(e.getMessage());
		}

		// Verify that the scaling policy was created
		DescribeScalingPoliciesRequest dspRequest = new DescribeScalingPoliciesRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceId(resourceID);

		try {
			DescribeScalingPoliciesResult dspResult = aaClient.describeScalingPolicies(dspRequest);
			System.out.println("DescribeScalingPolicies result: ");
			System.out.println(dspResult);
		} catch (Exception e) {
			e.printStackTrace();
			System.err.println("Unable to describe scaling policy: ");
			System.err.println(e.getMessage());
		}

	}

}

Desabilitar o Application Auto Scaling para uma tabela

O programa a seguir inverte o processo anterior. Ele remove a política de Auto Scaling e cancela o registro do destino dimensionável.

Java v2
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.applicationautoscaling.ApplicationAutoScalingClient;
import software.amazon.awssdk.services.applicationautoscaling.model.ApplicationAutoScalingException;
import software.amazon.awssdk.services.applicationautoscaling.model.DeleteScalingPolicyRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.DeregisterScalableTargetRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalableTargetsRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalableTargetsResponse;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalingPoliciesRequest;
import software.amazon.awssdk.services.applicationautoscaling.model.DescribeScalingPoliciesResponse;
import software.amazon.awssdk.services.applicationautoscaling.model.ScalableDimension;
import software.amazon.awssdk.services.applicationautoscaling.model.ServiceNamespace;

/**
 * Before running this Java V2 code example, set up your development environment, including your credentials.
 *
 * For more information, see the following documentation topic:
 *
 * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 */

public class DisableDynamoDBAutoscaling {
    public static void main(String[] args) {
        final String usage = """

            Usage:
               <tableId> <policyName>\s

            Where:
               tableId - The table Id value (for example, table/Music).\s
               policyName - The name of the policy (for example, $Music5-scaling-policy). 
        
            """;
        if (args.length != 2) {
            System.out.println(usage);
            System.exit(1);
        }

        ApplicationAutoScalingClient appAutoScalingClient = ApplicationAutoScalingClient.builder()
            .region(Region.US_EAST_1)
            .build();

        ServiceNamespace ns = ServiceNamespace.DYNAMODB;
        ScalableDimension tableWCUs = ScalableDimension.DYNAMODB_TABLE_WRITE_CAPACITY_UNITS;
        String tableId = args[0];
        String policyName = args[1];

        deletePolicy(appAutoScalingClient, policyName, tableWCUs, ns, tableId);
        verifyScalingPolicies(appAutoScalingClient, tableId, ns, tableWCUs);
        deregisterScalableTarget(appAutoScalingClient, tableId, ns, tableWCUs);
        verifyTarget(appAutoScalingClient, tableId, ns, tableWCUs);
    }

    public static void deletePolicy(ApplicationAutoScalingClient appAutoScalingClient, String policyName, ScalableDimension tableWCUs, ServiceNamespace ns, String tableId) {
        try {
            DeleteScalingPolicyRequest delSPRequest = DeleteScalingPolicyRequest.builder()
                .policyName(policyName)
                .scalableDimension(tableWCUs)
                .serviceNamespace(ns)
                .resourceId(tableId)
                .build();

            appAutoScalingClient.deleteScalingPolicy(delSPRequest);
            System.out.println(policyName +" was deleted successfully.");

        } catch (ApplicationAutoScalingException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
        }
    }

    // Verify that the scaling policy was deleted
    public static void verifyScalingPolicies(ApplicationAutoScalingClient appAutoScalingClient, String tableId, ServiceNamespace ns, ScalableDimension tableWCUs) {
        DescribeScalingPoliciesRequest dscRequest = DescribeScalingPoliciesRequest.builder()
            .scalableDimension(tableWCUs)
            .serviceNamespace(ns)
            .resourceId(tableId)
            .build();

        DescribeScalingPoliciesResponse response = appAutoScalingClient.describeScalingPolicies(dscRequest);
        System.out.println("DescribeScalableTargets result: ");
        System.out.println(response);
    }

    public static void deregisterScalableTarget(ApplicationAutoScalingClient appAutoScalingClient, String tableId, ServiceNamespace ns, ScalableDimension tableWCUs) {
        try {
            DeregisterScalableTargetRequest targetRequest = DeregisterScalableTargetRequest.builder()
                .scalableDimension(tableWCUs)
                .serviceNamespace(ns)
                .resourceId(tableId)
                .build();

            appAutoScalingClient.deregisterScalableTarget(targetRequest);
            System.out.println("The scalable target was deregistered.");

        } catch (ApplicationAutoScalingException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
        }
    }

    public static void verifyTarget(ApplicationAutoScalingClient appAutoScalingClient, String tableId, ServiceNamespace ns, ScalableDimension tableWCUs) {
        DescribeScalableTargetsRequest dscRequest = DescribeScalableTargetsRequest.builder()
            .scalableDimension(tableWCUs)
            .serviceNamespace(ns)
            .resourceIds(tableId)
            .build();

        DescribeScalableTargetsResponse response = appAutoScalingClient.describeScalableTargets(dscRequest);
        System.out.println("DescribeScalableTargets result: ");
        System.out.println(response);
    }
}
Java v1
package com.amazonaws.codesamples.autoscaling;

import com.amazonaws.services.applicationautoscaling.AWSApplicationAutoScalingClient;
import com.amazonaws.services.applicationautoscaling.model.DeleteScalingPolicyRequest;
import com.amazonaws.services.applicationautoscaling.model.DeregisterScalableTargetRequest;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalableTargetsRequest;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalableTargetsResult;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalingPoliciesRequest;
import com.amazonaws.services.applicationautoscaling.model.DescribeScalingPoliciesResult;
import com.amazonaws.services.applicationautoscaling.model.ScalableDimension;
import com.amazonaws.services.applicationautoscaling.model.ServiceNamespace;

public class DisableDynamoDBAutoscaling {

	static AWSApplicationAutoScalingClient aaClient = new AWSApplicationAutoScalingClient();

	public static void main(String args[]) {

		ServiceNamespace ns = ServiceNamespace.Dynamodb;
		ScalableDimension tableWCUs = ScalableDimension.DynamodbTableWriteCapacityUnits;
		String resourceID = "table/TestTable";

		// Delete the scaling policy
		DeleteScalingPolicyRequest delSPRequest = new DeleteScalingPolicyRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceId(resourceID)
				.withPolicyName("MyScalingPolicy");

		try {
			aaClient.deleteScalingPolicy(delSPRequest);
		} catch (Exception e) {
			System.err.println("Unable to delete scaling policy: ");
			System.err.println(e.getMessage());
		}

		// Verify that the scaling policy was deleted
		DescribeScalingPoliciesRequest descSPRequest = new DescribeScalingPoliciesRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceId(resourceID);

		try {
			DescribeScalingPoliciesResult dspResult = aaClient.describeScalingPolicies(descSPRequest);
			System.out.println("DescribeScalingPolicies result: ");
			System.out.println(dspResult);
		} catch (Exception e) {
			e.printStackTrace();
			System.err.println("Unable to describe scaling policy: ");
			System.err.println(e.getMessage());
		}

		System.out.println();

		// Remove the scalable target
		DeregisterScalableTargetRequest delSTRequest = new DeregisterScalableTargetRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceId(resourceID);

		try {
			aaClient.deregisterScalableTarget(delSTRequest);
		} catch (Exception e) {
			System.err.println("Unable to deregister scalable target: ");
			System.err.println(e.getMessage());
		}

		// Verify that the scalable target was removed
		DescribeScalableTargetsRequest dscRequest = new DescribeScalableTargetsRequest()
				.withServiceNamespace(ns)
				.withScalableDimension(tableWCUs)
				.withResourceIds(resourceID);

		try {
			DescribeScalableTargetsResult dsaResult = aaClient.describeScalableTargets(dscRequest);
			System.out.println("DescribeScalableTargets result: ");
			System.out.println(dsaResult);
			System.out.println();
		} catch (Exception e) {
			System.err.println("Unable to describe scalable target: ");
			System.err.println(e.getMessage());
		}

	}

}