fargate-service-metric-factory.ts

import { FargateService } from 'aws-cdk-lib/aws-ecs';
import {
    DEFAULT_METRIC_PERIOD, Metric, MetricOptions, MetricStatistic,
} from '../../common/metrics';
import { MetricFactory } from '../metric-factory';
import { ResourceMetricProps } from '../resource-metric';

const EcsContainerInsightsNamespace = 'ECS/ContainerInsights';
const COLOR_NOT_SPECIFIED = undefined;
/**
 * Network Load Balanced Fargate Service Metric Factory Props.
 * Defines the metrics for the resource against which monitoring can be done.
 *
 */
export interface FargateServiceMetricFactoryProps extends ResourceMetricProps {
    /**
     * Fargate service instance. Must pass this or fargateServiceCore.
     */
    readonly fargateServiceCore: FargateService;

    /**
     * Metric Options for the Cpu Maximum utilization
     *
     *  Refer: https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-ecs.FargateService.html#metricwbrcpuwbrutilizationprops
     */
    readonly cpuUtilizationPercentMetricOptions?: MetricOptions;

    /**
     * Metric Options for the Memory Maximum utilization.
     *
     * Refer : https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-ecs.FargateService.html#metricwbrmemorywbrutilizationprops
     */
    readonly memoryUtilizationPercentMetricOptions?: MetricOptions;
    /**
     * Metric Options for the Healthy Hosts Count.
     */
    readonly healthyHostsMetricOptions?: MetricOptions;
    /**
     * Metric Options for Disk Utilization provided by ContainerInsights
     */
    readonly diskUtilizationMetricOptions?: MetricOptions;
    /**
     * The metric statistic for the running tasks on which metric has to be formed.
     */
    readonly runningTasksMetricStatistic ?: MetricStatistic;
}

export class FargateServiceMetricFactory {
    private readonly props: FargateServiceMetricFactoryProps;

    protected readonly metricFactory: MetricFactory;

    private readonly fargateServiceCore: FargateService;

    constructor(metricFactory: MetricFactory, props: FargateServiceMetricFactoryProps) {
        this.props = props;
        this.metricFactory = metricFactory;
        this.fargateServiceCore = props.fargateServiceCore;
    }

    metricClusterCpuUtilizationInPercent() : Metric {
        return this.fargateServiceCore.metricCpuUtilization({
            label: 'Cluster CPU Utilization',
            period: this.props.cpuUtilizationPercentMetricOptions?.period ?? DEFAULT_METRIC_PERIOD,
        });
    }

    metricClusterMemoryUtilizationInPercent(): Metric {
        return this.fargateServiceCore.metricMemoryUtilization({
            label: 'Cluster Memory Utilization',
            period: this.props.memoryUtilizationPercentMetricOptions?.period ?? DEFAULT_METRIC_PERIOD,
        });
    }

    metricRunningTaskCount(): Metric {
        return this.metricFactory.createMetric(
            'RunningTaskCount',
            this.props.runningTasksMetricStatistic ?? MetricStatistic.AVERAGE,
            'Running Tasks',
            {
                ServiceName: this.fargateServiceCore.serviceName,
                ClusterName: this.fargateServiceCore.cluster.clusterName,
            },
            COLOR_NOT_SPECIFIED,
            EcsContainerInsightsNamespace,
        );
    }

    metricDiskUtilization(): Metric {
        const ephemeralStorareReserved = this.metricFactory
            .createMetric(
                'EphemeralStorageReserved',
                MetricStatistic.SUM,
                'Ephemeral GiB Reserved',
                {
                    ClusterName: this.fargateServiceCore.cluster.clusterName,
                    ServiceName: this.fargateServiceCore.serviceName,
                },
                COLOR_NOT_SPECIFIED,
                EcsContainerInsightsNamespace,
                this.props.diskUtilizationMetricOptions?.period ?? DEFAULT_METRIC_PERIOD,
            );
        const ephemeralStorageUtilized = this.metricFactory
            .createMetric(
                'EphemeralStorageUtilized',
                MetricStatistic.SUM,
                'Ephemeral GiB Utilized',
                {
                    ClusterName: this.fargateServiceCore.cluster.clusterName,
                    ServiceName: this.fargateServiceCore.serviceName,
                },
                COLOR_NOT_SPECIFIED,
                EcsContainerInsightsNamespace,
                this.props.diskUtilizationMetricOptions?.period ?? DEFAULT_METRIC_PERIOD,
            );

        return this.metricFactory.createMetricMath(
            'storageUtilized * 100 / storageReserved',
            {
                storageReserved: ephemeralStorareReserved,
                storageUtilized: ephemeralStorageUtilized,
            },
            'DiskSpaceUtilization',
            COLOR_NOT_SPECIFIED,
            this.props.diskUtilizationMetricOptions?.period ?? DEFAULT_METRIC_PERIOD,
        );
    }

    // JSII forbids 'get*' method names because they conflict with Java autogenerated code
    provideFargateServiceCore(): FargateService {
        return this.fargateServiceCore;
    }
}