feat(rds): add support for Aurora Serverless Clusters (#395)

Added new AuroraCluster Monitoring with Aurora specific metrics/alarms.

Fixes #217

---

_By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache-2.0 license_

Author: zqumei0

API.md

@@ -65,6 +65,7 @@ You can browse the documentation at https://constructs.dev/packages/cdk-monitori
 | AWS API Gateway (REST API) (`.monitorApiGateway()`) | TPS, latency, errors | Latency, error count/rate, low/high TPS | To see metrics, you have to enable Advanced Monitoring |
 | AWS API Gateway V2 (HTTP API) (`.monitorApiGatewayV2HttpApi()`) | TPS, latency, errors | Latency, error count/rate, low/high TPS | To see route level metrics, you have to enable Advanced Monitoring |
 | AWS AppSync (GraphQL API) (`.monitorAppSyncApi()`) | TPS, latency, errors | Latency, error count/rate, low/high TPS | |
+| Amazon Aurora (`.monitorAuroraCluster()`) | Query duration, connections, latency, CPU usage, Serverless Database Capacity | Connections, Serverless Database Capacity and CPU usage | |
 | AWS Billing (`.monitorBilling()`) | AWS account cost | Total cost (anomaly) | [Requires enabling](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/gs_monitor_estimated_charges_with_cloudwatch.html#gs_turning_on_billing_metrics) the **Receive Billing Alerts** option in AWS Console / Billing Preferences |
 | AWS Certificate Manager (`.monitorCertificate()`) | Certificate expiration | Days until expiration | |
 | AWS CloudFront (`.monitorCloudFrontDistribution()`) | TPS, traffic, latency, errors | Error rate, low/high TPS | |

README.md

@@ -0,0 +1,39 @@
+import {
+  ComparisonOperator,
+  TreatMissingData,
+} from "aws-cdk-lib/aws-cloudwatch";
+
+import { AlarmFactory, CustomAlarmThreshold } from "../../alarm";
+import { MetricWithAlarmSupport } from "../../metric";
+
+export interface HighServerlessDatabaseCapacityThreshold
+  extends CustomAlarmThreshold {
+  readonly maxServerlessDatabaseCapacity: number;
+}
+
+export class AuroraAlarmFactory {
+  protected readonly alarmFactory: AlarmFactory;
+
+  constructor(alarmFactory: AlarmFactory) {
+    this.alarmFactory = alarmFactory;
+  }
+
+  addMaxServerlessDatabaseCapacity(
+    metric: MetricWithAlarmSupport,
+    props: HighServerlessDatabaseCapacityThreshold,
+    disambiguator?: string
+  ) {
+    return this.alarmFactory.addAlarm(metric, {
+      treatMissingData:
+        props.treatMissingDataOverride ?? TreatMissingData.MISSING,
+      comparisonOperator:
+        props.comparisonOperatorOverride ??
+        ComparisonOperator.GREATER_THAN_THRESHOLD,
+      ...props,
+      disambiguator,
+      threshold: props.maxServerlessDatabaseCapacity,
+      alarmNameSuffix: "Serverless-Database-Capacity-High",
+      alarmDescription: "Serverless Database Capacity usage is too high.",
+    });
+  }
+}

lib/common/monitoring/alarms/AuroraAlarmFactory.ts

@@ -37,6 +37,25 @@ export class UsageAlarmFactory {
     this.alarmFactory = alarmFactory;
   }
 
+  addMaxUsageCountAlarm(
+    metric: MetricWithAlarmSupport,
+    props: UsageCountThreshold,
+    disambiguator?: string
+  ) {
+    return this.alarmFactory.addAlarm(metric, {
+      treatMissingData:
+        props.treatMissingDataOverride ?? TreatMissingData.MISSING,
+      comparisonOperator:
+        props.comparisonOperatorOverride ??
+        ComparisonOperator.GREATER_THAN_THRESHOLD,
+      ...props,
+      disambiguator,
+      threshold: props.maxUsageCount,
+      alarmNameSuffix: "Usage-Count",
+      alarmDescription: "The count is too high.",
+    });
+  }
+
   addMinUsageCountAlarm(
     percentMetric: MetricWithAlarmSupport,
     props: MinUsageCountThreshold,

lib/common/monitoring/alarms/UsageAlarmFactory.ts

@@ -1,5 +1,6 @@
 export * from "./AgeAlarmFactory";
 export * from "./AnomalyDetectingAlarmFactory";
+export * from "./AuroraAlarmFactory";
 export * from "./CustomAlarmFactory";
 export * from "./ConnectionAlarmFactory";
 export * from "./DynamoAlarmFactory";

lib/common/monitoring/alarms/index.ts

@@ -2,6 +2,7 @@ import {
   ApiGatewayMonitoringOptions,
   ApiGatewayV2MonitoringOptions,
   AppSyncMonitoringOptions,
+  AuroraClusterMonitoringOptions,
   AutoScalingGroupMonitoringOptions,
   BillingMonitoringOptions,
   CertificateManagerMonitoringOptions,
@@ -47,6 +48,7 @@ export interface MonitoringAspectProps {
   readonly apiGateway?: MonitoringAspectType<ApiGatewayMonitoringOptions>;
   readonly apiGatewayV2?: MonitoringAspectType<ApiGatewayV2MonitoringOptions>;
   readonly appSync?: MonitoringAspectType<AppSyncMonitoringOptions>;
+  readonly auroraCluster?: MonitoringAspectType<AuroraClusterMonitoringOptions>;
   readonly autoScalingGroup?: MonitoringAspectType<AutoScalingGroupMonitoringOptions>;
   readonly billing?: MonitoringAspectType<BillingMonitoringOptions>;
   readonly cloudFront?: MonitoringAspectType<CloudFrontDistributionMonitoringOptions>;

lib/facade/IMonitoringAspect.ts

@@ -52,6 +52,7 @@ export class MonitoringAspect implements IAspect {
     this.monitorApiGateway(node);
     this.monitorApiGatewayV2(node);
     this.monitorAppSync(node);
+    this.monitorAuroraCluster(node);
     this.monitorAutoScalingGroup(node);
     this.monitorCloudFront(node);
     this.monitorCodeBuild(node);
@@ -135,6 +136,19 @@ export class MonitoringAspect implements IAspect {
     }
   }
 
+  private monitorAuroraCluster(node: IConstruct) {
+    const [isEnabled, props] = this.getMonitoringDetails(
+      this.props.auroraCluster
+    );
+    if (isEnabled && node instanceof rds.ServerlessCluster) {
+      this.monitoringFacade.monitorAuroraCluster({
+        cluster: node,
+        alarmFriendlyName: node.node.path,
+        ...props,
+      });
+    }
+  }
+
   private monitorAutoScalingGroup(node: IConstruct) {
     const [isEnabled, props] = this.getMonitoringDetails(
       this.props.autoScalingGroup

lib/facade/MonitoringAspect.ts

@@ -38,6 +38,8 @@ import {
   ApiGatewayV2HttpApiMonitoringProps,
   AppSyncMonitoring,
   AppSyncMonitoringProps,
+  AuroraClusterMonitoring,
+  AuroraClusterMonitoringProps,
   AutoScalingGroupMonitoring,
   AutoScalingGroupMonitoringProps,
   BillingMonitoring,
@@ -415,6 +417,12 @@ export class MonitoringFacade extends MonitoringScope {
     return this;
   }
 
+  monitorAuroraCluster(props: AuroraClusterMonitoringProps) {
+    const segment = new AuroraClusterMonitoring(this, props);
+    this.addSegment(segment, props);
+    return this;
+  }
+
   monitorCertificate(props: CertificateManagerMonitoringProps) {
     const segment = new CertificateManagerMonitoring(this, props);
     this.addSegment(segment, props);