Uso del AWS SDK para configurar escalado automático en tablas de Amazon DynamoDB
Además de utilizar la AWS Management Console y la AWS Command Line Interface (AWS CLI), puede escribir aplicaciones que interaccionen con el escalado automático de Amazon DynamoDB. Esta sección contiene dos programas de Java que puede utilizar para probar esta funcionalidad:
-
EnableDynamoDBAutoscaling.java
-
DisableDynamoDBAutoscaling.java
Habilitación de Auto Scaling de aplicaciones para una tabla
En el siguiente programa se muestra un ejemplo de cómo configurar una política de escalado automático para una tabla de DynamoDB (TestTable
). Funciona de la siguiente manera:
-
El programa registra las unidades de capacidad de escritura como objetivo escalable de
TestTable
. El rango de esta métrica está comprendido entre 5 y 10 unidades de capacidad de escritura. -
Después de crear el objetivo escalable, el programa crea una configuración de seguimiento del objetivo. La política está dirigida a mantener una proporción objetivo del 50 % entre la capacidad de escritura consumida y la capacidad de escritura provisionada.
-
Después, el programa crea la política de escalado basada en la configuración de seguimiento del objetivo.
nota
Cuando se elimina manualmente una tabla o réplica de tabla global, no se eliminan automáticamente los destinos escalables asociados, las políticas de escalado o las alarmas de 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
-
El programa requiere que se suministre el nombre de recurso de Amazon (ARN) de un rol vinculado a un servicio de Auto Scaling de aplicaciones válido. (Por ejemplo:
arn:aws:iam::122517410325:role/AWSServiceRoleForApplicationAutoScaling_DynamoDBTable
.) En el siguiente programa, sustituyaSERVICE_ROLE_ARN_GOES_HERE
por el 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()); } } }
Desactivación de Auto Scaling de aplicaciones para una tabla
En el siguiente programa se invierte el proceso anterior. Se elimina la política de escalado automático y, a continuación, se anula el registro del objetivo escalable.
- 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()); } } }