feat: adding monitoring support for CloudWatch Canary (#75)

Author: voho

API.md

@@ -90,6 +90,7 @@ You can also browse the documentation at https://constructs.dev/packages/cdk-mon
 | AWS Billing (`.monitorBilling()`) | AWS account cost | | [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 | |
+| AWS CloudWatch Synthetics Canary (`.monitorSyntheticsCanary()`) | Latency, error count/rate | Error count/rate, latency | |
 | AWS CodeBuild (`.monitorCodeBuildProject()`) | Build counts (total, successful, failed), failed rate, duration | Failed build count/rate, duration | |
 | AWS DynamoDB (`.monitorDynamoTable()`) | Read and write capacity provisioned / used | Consumed capacity, throttling, latency, errors | |
 | AWS DynamoDB Global Secondary Index (`.monitorDynamoTableGlobalSecondaryIndex()`) | Read and write capacity, indexing progress, throttled events | | |

README.md

@@ -21,6 +21,7 @@ import * as secretsmanager from "monocdk/aws-secretsmanager";
 import * as sns from "monocdk/aws-sns";
 import * as sqs from "monocdk/aws-sqs";
 import * as stepfunctions from "monocdk/aws-stepfunctions";
+import * as synthetics from "monocdk/aws-synthetics";
 
 import { ElastiCacheClusterType } from "../monitoring";
 import { MonitoringAspectProps, MonitoringAspectType } from "./aspect-types";
@@ -61,7 +62,8 @@ export class MonitoringAspect implements IAspect {
     this.monitorSecretsManager(node);
     this.monitorSns(node);
     this.monitorSqs(node);
-    this.monitorStepFuntions(node);
+    this.monitorStepFunctions(node);
+    this.monitorSyntheticsCanaries(node);
 
     if (!this.addedNodeIndependentMonitoringToScope) {
       this.addedNodeIndependentMonitoringToScope = true;
@@ -340,7 +342,7 @@ export class MonitoringAspect implements IAspect {
     }
   }
 
-  private monitorStepFuntions(node: IConstruct) {
+  private monitorStepFunctions(node: IConstruct) {
     const [isEnabled, props] = this.getMonitoringDetails(
       this.props.stepFunctions
     );
@@ -351,6 +353,18 @@ export class MonitoringAspect implements IAspect {
       });
     }
   }
+
+  private monitorSyntheticsCanaries(node: IConstruct) {
+    const [isEnabled, props] = this.getMonitoringDetails(
+      this.props.syntheticsCanaries
+    );
+    if (isEnabled && node instanceof synthetics.Canary) {
+      this.monitoringFacade.monitorSyntheticsCanary({
+        canary: node,
+        ...props,
+      });
+    }
+  }
 }
 
 export * from "./aspect-types";

lib/facade/MonitoringAspect.ts

@@ -101,6 +101,8 @@ import {
   StepFunctionServiceIntegrationMonitoringProps,
   getQueueProcessingEc2ServiceMonitoring,
   getQueueProcessingFargateServiceMonitoring,
+  SyntheticsCanaryMonitoringProps,
+  SyntheticsCanaryMonitoring,
 } from "../monitoring";
 import { MonitoringAspect, MonitoringAspectProps } from "./MonitoringAspect";
 
@@ -605,6 +607,12 @@ export class MonitoringFacade extends MonitoringScope {
     return this;
   }
 
+  monitorSyntheticsCanary(props: SyntheticsCanaryMonitoringProps) {
+    const segment = new SyntheticsCanaryMonitoring(this, props);
+    this.addSegment(segment, props);
+    return this;
+  }
+
   monitorBilling(props?: BillingMonitoringProps) {
     const segment = new BillingMonitoring(this, props ?? {});
     this.addSegment(segment, props);

lib/facade/MonitoringFacade.ts

@@ -23,6 +23,7 @@ import {
   SnsTopicMonitoringOptions,
   SqsQueueMonitoringOptions,
   StepFunctionMonitoringOptions,
+  SyntheticsCanaryMonitoringOptions,
 } from "../monitoring";
 
 export interface MonitoringAspectType<T> {
@@ -64,4 +65,5 @@ export interface MonitoringAspectProps {
   readonly sns?: MonitoringAspectType<SnsTopicMonitoringOptions>;
   readonly sqs?: MonitoringAspectType<SqsQueueMonitoringOptions>;
   readonly stepFunctions?: MonitoringAspectType<StepFunctionMonitoringOptions>;
+  readonly syntheticsCanaries?: MonitoringAspectType<SyntheticsCanaryMonitoringOptions>;
 }

lib/facade/aspect-types.ts

@@ -0,0 +1,101 @@
+import { DimensionHash } from "monocdk/aws-cloudwatch";
+import { Canary } from "monocdk/aws-synthetics";
+import {
+  MetricFactory,
+  MetricStatistic,
+  RateComputationMethod,
+} from "../../common/index";
+
+const MetricNamespace = "CloudWatchSynthetics";
+
+export interface SyntheticsCanaryMetricFactoryProps {
+  /**
+   * CloudWatch Canary to monitor
+   */
+  readonly canary: Canary;
+  /**
+   * Method used to calculate relative rates
+   * @default average
+   */
+  readonly rateComputationMethod?: RateComputationMethod;
+}
+
+export class SyntheticsCanaryMetricFactory {
+  protected readonly canary: Canary;
+  protected readonly metricFactory: MetricFactory;
+  protected readonly rateComputationMethod: RateComputationMethod;
+  protected readonly dimensions: DimensionHash;
+
+  constructor(
+    metricFactory: MetricFactory,
+    props: SyntheticsCanaryMetricFactoryProps
+  ) {
+    this.canary = props.canary;
+    this.metricFactory = metricFactory;
+    this.rateComputationMethod =
+      props.rateComputationMethod ?? RateComputationMethod.AVERAGE;
+    this.dimensions = {
+      CanaryName: props.canary.canaryName,
+    };
+  }
+
+  metricLatencyAverageInMillis() {
+    return this.metricFactory.adaptMetric(
+      this.canary.metricDuration({
+        label: "Average",
+        statistic: MetricStatistic.AVERAGE,
+      })
+    );
+  }
+
+  metricSuccessInPercent() {
+    return this.metricFactory.adaptMetric(
+      this.canary.metricSuccessPercent({
+        label: "Success Rate",
+        statistic: MetricStatistic.AVERAGE,
+      })
+    );
+  }
+
+  metric4xxErrorCount() {
+    return this.metricFactory.createMetric(
+      "4xx",
+      MetricStatistic.SUM,
+      "4xx",
+      this.dimensions,
+      undefined,
+      MetricNamespace
+    );
+  }
+
+  metric4xxErrorRate() {
+    const metric = this.metric4xxErrorCount();
+    return this.metricFactory.toRate(
+      metric,
+      this.rateComputationMethod,
+      false,
+      "errors"
+    );
+  }
+
+  metric5xxFaultCount() {
+    return this.metricFactory.createMetric(
+      "5xx",
+      MetricStatistic.SUM,
+      "5xx",
+      this.dimensions,
+      undefined,
+      MetricNamespace
+    );
+  }
+
+  metric5xxFaultRate() {
+    const metric = this.metric5xxFaultCount();
+    return this.metricFactory.toRate(
+      metric,
+      this.rateComputationMethod,
+      false,
+      "faults"
+    );
+  }
+}