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v2.274.0

ApplicationLoadBalancedFargateService L3 construct ​

A Fargate service running on an ECS cluster fronted by an application load balancer.

Example ​

ts
declare const cluster: ecs.Cluster;
const loadBalancedFargateService = new ecsPatterns.ApplicationLoadBalancedFargateService(this, 'Service', {
  cluster,
  memoryLimitMiB: 1024,
  desiredCount: 1,
  cpu: 512,
  taskImageOptions: {
    image: ecs.ContainerImage.fromRegistry("amazon/amazon-ecs-sample"),
  },
  minHealthyPercent: 100,
});

const scalableTarget = loadBalancedFargateService.service.autoScaleTaskCount({
  minCapacity: 1,
  maxCapacity: 20,
});

scalableTarget.scaleOnCpuUtilization('CpuScaling', {
  targetUtilizationPercent: 50,
});

scalableTarget.scaleOnMemoryUtilization('MemoryScaling', {
  targetUtilizationPercent: 50,
});
python
# cluster: ecs.Cluster

load_balanced_fargate_service = ecs_patterns.ApplicationLoadBalancedFargateService(self, "Service",
    cluster=cluster,
    memory_limit_mi_b=1024,
    desired_count=1,
    cpu=512,
    task_image_options=ecsPatterns.ApplicationLoadBalancedTaskImageOptions(
        image=ecs.ContainerImage.from_registry("amazon/amazon-ecs-sample")
    ),
    min_healthy_percent=100
)

scalable_target = load_balanced_fargate_service.service.auto_scale_task_count(
    min_capacity=1,
    max_capacity=20
)

scalable_target.scale_on_cpu_utilization("CpuScaling",
    target_utilization_percent=50
)

scalable_target.scale_on_memory_utilization("MemoryScaling",
    target_utilization_percent=50
)
java
Cluster cluster;

ApplicationLoadBalancedFargateService loadBalancedFargateService = ApplicationLoadBalancedFargateService.Builder.create(this, "Service")
        .cluster(cluster)
        .memoryLimitMiB(1024)
        .desiredCount(1)
        .cpu(512)
        .taskImageOptions(ApplicationLoadBalancedTaskImageOptions.builder()
                .image(ContainerImage.fromRegistry("amazon/amazon-ecs-sample"))
                .build())
        .minHealthyPercent(100)
        .build();

ScalableTaskCount scalableTarget = loadBalancedFargateService.service.autoScaleTaskCount(EnableScalingProps.builder()
        .minCapacity(1)
        .maxCapacity(20)
        .build());

scalableTarget.scaleOnCpuUtilization("CpuScaling", CpuUtilizationScalingProps.builder()
        .targetUtilizationPercent(50)
        .build());

scalableTarget.scaleOnMemoryUtilization("MemoryScaling", MemoryUtilizationScalingProps.builder()
        .targetUtilizationPercent(50)
        .build());
csharp
// Install: dotnet add package Amazon.CDK.Lib
Cluster cluster;

var loadBalancedFargateService = new ApplicationLoadBalancedFargateService(this, "Service", new ApplicationLoadBalancedFargateServiceProps {
    Cluster = cluster,
    MemoryLimitMiB = 1024,
    DesiredCount = 1,
    Cpu = 512,
    TaskImageOptions = new ApplicationLoadBalancedTaskImageOptions {
        Image = ContainerImage.FromRegistry("amazon/amazon-ecs-sample")
    },
    MinHealthyPercent = 100
});

var scalableTarget = loadBalancedFargateService.Service.AutoScaleTaskCount(new EnableScalingProps {
    MinCapacity = 1,
    MaxCapacity = 20
});

scalableTarget.ScaleOnCpuUtilization("CpuScaling", new CpuUtilizationScalingProps {
    TargetUtilizationPercent = 50
});

scalableTarget.ScaleOnMemoryUtilization("MemoryScaling", new MemoryUtilizationScalingProps {
    TargetUtilizationPercent = 50
});
go
// Install: go get github.com/aws/aws-cdk-go/awscdk/v2
var cluster Cluster

loadBalancedFargateService := ecsPatterns.NewApplicationLoadBalancedFargateService(this, jsii.String("Service"), &ApplicationLoadBalancedFargateServiceProps{
	Cluster: Cluster,
	MemoryLimitMiB: jsii.Number(1024),
	DesiredCount: jsii.Number(1),
	Cpu: jsii.Number(512),
	TaskImageOptions: &ApplicationLoadBalancedTaskImageOptions{
		Image: ecs.ContainerImage_FromRegistry(jsii.String("amazon/amazon-ecs-sample")),
	},
	MinHealthyPercent: jsii.Number(100),
})

scalableTarget := loadBalancedFargateService.Service.AutoScaleTaskCount(&EnableScalingProps{
	MinCapacity: jsii.Number(1),
	MaxCapacity: jsii.Number(20),
})

scalableTarget.ScaleOnCpuUtilization(jsii.String("CpuScaling"), &CpuUtilizationScalingProps{
	TargetUtilizationPercent: jsii.Number(50),
})

scalableTarget.ScaleOnMemoryUtilization(jsii.String("MemoryScaling"), &MemoryUtilizationScalingProps{
	TargetUtilizationPercent: jsii.Number(50),
})

Initializer ​

ts
new ApplicationLoadBalancedFargateService(scope: Construct, id: string, props?: ApplicationLoadBalancedFargateServiceProps)
python
ApplicationLoadBalancedFargateService(scope: Construct, id: str, props: typing.Optional[ApplicationLoadBalancedFargateServiceProps] = None)
java
new ApplicationLoadBalancedFargateService(Construct scope, String id, ApplicationLoadBalancedFargateServiceProps props)
csharp
new ApplicationLoadBalancedFargateService(Construct scope, string id, ApplicationLoadBalancedFargateServiceProps? props = null)
go
NewApplicationLoadBalancedFargateService(Scope Construct, Id *string, Props ApplicationLoadBalancedFargateServiceProps)

Construct Props ​

assignPublicIpoptionalbooleanassign_public_ipoptionalboolassignPublicIpoptionalBooleanAssignPublicIpoptionalboolAssignPublicIpoptional*bool= false#
Determines whether the service will be assigned a public IP address.
capacityProviderStrategiesoptionalCapacityProviderStrategy[]capacity_provider_strategiesoptionaltyping.List[CapacityProviderStrategy]capacityProviderStrategiesoptionalList<CapacityProviderStrategy>CapacityProviderStrategiesoptionalCapacityProviderStrategy[]CapacityProviderStrategiesoptional*[]CapacityProviderStrategy= undefined#
A list of Capacity Provider strategies used to place a service.
certificateoptionalICertificatecertificateoptionalICertificatecertificateoptionalICertificateCertificateoptionalICertificateCertificateoptionalICertificate#
Certificate Manager certificate to associate with the load balancer.

Default: No certificate associated with the load balancer, if using the HTTP protocol. For HTTPS, a DNS-validated certificate will be created for the load balancer's specified domain name if a domain name and domain zone are specified.

Setting this option will set the load balancer protocol to HTTPS.

circuitBreakeroptionalDeploymentCircuitBreakercircuit_breakeroptionalDeploymentCircuitBreakercircuitBreakeroptionalDeploymentCircuitBreakerCircuitBreakeroptionalDeploymentCircuitBreakerCircuitBreakeroptionalDeploymentCircuitBreaker= disabled#
Whether to enable the deployment circuit breaker.

If this property is defined, circuit breaker will be implicitly enabled.

cloudMapOptionsoptionalCloudMapOptionscloud_map_optionsoptionalCloudMapOptionscloudMapOptionsoptionalCloudMapOptionsCloudMapOptionsoptionalCloudMapOptionsCloudMapOptionsoptionalCloudMapOptions#
The options for configuring an Amazon ECS service to use service discovery.

Default: AWS Cloud Map service discovery is not enabled.

clusteroptionalIClusterclusteroptionalIClusterclusteroptionalIClusterClusteroptionalIClusterClusteroptionalICluster#
The name of the cluster that hosts the service.

Default: create a new cluster; if both cluster and vpc are omitted, a new VPC will be created for you.

If a cluster is specified, the vpc construct should be omitted. Alternatively, you can omit both cluster and vpc.

containerCpuoptionalnumbercontainer_cpuoptionalint | floatcontainerCpuoptionalNumberContainerCpuoptionaldoubleContainerCpuoptional*float64#
The minimum number of CPU units to reserve for the container.

Default: No minimum CPU units reserved.

containerMemoryLimitMiBoptionalnumbercontainer_memory_limit_mi_boptionalint | floatcontainerMemoryLimitMiBoptionalNumberContainerMemoryLimitMiBoptionaldoubleContainerMemoryLimitMiBoptional*float64#
The amount (in MiB) of memory to present to the container.

Default: No memory limit.

If your container attempts to exceed the allocated memory, the container is terminated.

cpuoptionalnumbercpuoptionalint | floatcpuoptionalNumberCpuoptionaldoubleCpuoptional*float64= 256#
The number of cpu units used by the task.
notes

Valid values, which determines your range of valid values for the memory parameter:

256 (.25 vCPU) - Available memory values: 0.5GB, 1GB, 2GB

512 (.5 vCPU) - Available memory values: 1GB, 2GB, 3GB, 4GB

1024 (1 vCPU) - Available memory values: 2GB, 3GB, 4GB, 5GB, 6GB, 7GB, 8GB

2048 (2 vCPU) - Available memory values: Between 4GB and 16GB in 1GB increments

4096 (4 vCPU) - Available memory values: Between 8GB and 30GB in 1GB increments

8192 (8 vCPU) - Available memory values: Between 16GB and 60GB in 4GB increments

16384 (16 vCPU) - Available memory values: Between 32GB and 120GB in 8GB increments

This default is set in the underlying FargateTaskDefinition construct.

deploymentControlleroptionalDeploymentControllerdeployment_controlleroptionalDeploymentControllerdeploymentControlleroptionalDeploymentControllerDeploymentControlleroptionalDeploymentControllerDeploymentControlleroptionalDeploymentController#
Specifies which deployment controller to use for the service.

Default: Rolling update (ECS)

For more information, see Amazon ECS Deployment Types

desiredCountoptionalnumberdesired_countoptionalint | floatdesiredCountoptionalNumberDesiredCountoptionaldoubleDesiredCountoptional*float64#
The desired number of instantiations of the task definition to keep running on the service.

Default: The default is 1 for all new services and uses the existing service's desired count when updating an existing service.

The minimum value is 1

domainNameoptionalstringdomain_nameoptionalstrdomainNameoptionalStringDomainNameoptionalstringDomainNameoptional*string#
The domain name for the service, e.g. "api.example.com.".

Default: No domain name.

domainZoneoptionalIHostedZonedomain_zoneoptionalIHostedZonedomainZoneoptionalIHostedZoneDomainZoneoptionalIHostedZoneDomainZoneoptionalIHostedZone#
The Route53 hosted zone for the domain, e.g. "example.com.".

Default: No Route53 hosted domain zone.

enableECSManagedTagsoptionalbooleanenable_ecs_managed_tagsoptionalboolenableECSManagedTagsoptionalBooleanEnableECSManagedTagsoptionalboolEnableECSManagedTagsoptional*bool= false#
Specifies whether to enable Amazon ECS managed tags for the tasks within the service.

For more information, see Tagging Your Amazon ECS Resources

enableExecuteCommandoptionalbooleanenable_execute_commandoptionalboolenableExecuteCommandoptionalBooleanEnableExecuteCommandoptionalboolEnableExecuteCommandoptional*bool= false#
Whether ECS Exec should be enabled.
ephemeralStorageGiBoptionalnumberephemeral_storage_gi_boptionalint | floatephemeralStorageGiBoptionalNumberEphemeralStorageGiBoptionaldoubleEphemeralStorageGiBoptional*float64#
The amount (in GiB) of ephemeral storage to be allocated to the task.

Default: Undefined, in which case, the task will receive 20GiB ephemeral storage.

The minimum supported value is 21 GiB and the maximum supported value is 200 GiB.

Only supported in Fargate platform version 1.4.0 or later.

healthCheckoptionalHealthCheckhealth_checkoptionalHealthCheckhealthCheckoptionalHealthCheckHealthCheckoptionalHealthCheckHealthCheckoptionalHealthCheck#
The health check command and associated configuration parameters for the container.

Default: Health check configuration from container.

healthCheckGracePeriodoptionalDurationhealth_check_grace_periodoptionalDurationhealthCheckGracePeriodoptionalDurationHealthCheckGracePeriodoptionalDurationHealthCheckGracePeriodoptionalDuration#
The period of time, in seconds, that the Amazon ECS service scheduler ignores unhealthy Elastic Load Balancing target health checks after a task has first started.

Default: defaults to 60 seconds if at least one load balancer is in-use and it is not already set

idleTimeoutoptionalDurationidle_timeoutoptionalDurationidleTimeoutoptionalDurationIdleTimeoutoptionalDurationIdleTimeoutoptionalDuration#
The load balancer idle timeout, in seconds.

Default: CloudFormation sets idle timeout to 60 seconds

Can be between 1 and 4000 seconds

ipAddressTypeoptionalIpAddressTypeip_address_typeoptionalIpAddressTypeipAddressTypeoptionalIpAddressTypeIpAddressTypeoptionalIpAddressTypeIpAddressTypeoptionalIpAddressType= IpAddressType.IPV4#
The type of IP address to use.
listenerPortoptionalnumberlistener_portoptionalint | floatlistenerPortoptionalNumberListenerPortoptionaldoubleListenerPortoptional*float64#
Listener port of the application load balancer that will serve traffic to the service.

Default: The default listener port is determined from the protocol (port 80 for HTTP, port 443 for HTTPS). A domain name and zone must be also be specified if using HTTPS.

loadBalanceroptionalIApplicationLoadBalancerload_balanceroptionalIApplicationLoadBalancerloadBalanceroptionalIApplicationLoadBalancerLoadBalanceroptionalIApplicationLoadBalancerLoadBalanceroptionalIApplicationLoadBalancer#
The application load balancer that will serve traffic to the service.

Default: a new load balancer will be created.

The VPC attribute of a load balancer must be specified for it to be used to create a new service with this pattern.

[disable-awslint:ref-via-interface]

loadBalancerNameoptionalstringload_balancer_nameoptionalstrloadBalancerNameoptionalStringLoadBalancerNameoptionalstringLoadBalancerNameoptional*string#
Name of the load balancer.

Default: Automatically generated name.

maxHealthyPercentoptionalnumbermax_healthy_percentoptionalint | floatmaxHealthyPercentoptionalNumberMaxHealthyPercentoptionaldoubleMaxHealthyPercentoptional*float64#
The maximum number of tasks, specified as a percentage of the Amazon ECS service's DesiredCount value, that can run in a service during a deployment.

Default: 100 if daemon, otherwise 200

memoryLimitMiBoptionalnumbermemory_limit_mi_boptionalint | floatmemoryLimitMiBoptionalNumberMemoryLimitMiBoptionaldoubleMemoryLimitMiBoptional*float64= 512#
The amount (in MiB) of memory used by the task.
notes

This field is required and you must use one of the following values, which determines your range of valid values for the cpu parameter:

512 (0.5 GB), 1024 (1 GB), 2048 (2 GB) - Available cpu values: 256 (.25 vCPU)

1024 (1 GB), 2048 (2 GB), 3072 (3 GB), 4096 (4 GB) - Available cpu values: 512 (.5 vCPU)

2048 (2 GB), 3072 (3 GB), 4096 (4 GB), 5120 (5 GB), 6144 (6 GB), 7168 (7 GB), 8192 (8 GB) - Available cpu values: 1024 (1 vCPU)

Between 4096 (4 GB) and 16384 (16 GB) in increments of 1024 (1 GB) - Available cpu values: 2048 (2 vCPU)

Between 8192 (8 GB) and 30720 (30 GB) in increments of 1024 (1 GB) - Available cpu values: 4096 (4 vCPU)

Between 16384 (16 GB) and 61440 (60 GB) in increments of 4096 (4 GB) - Available cpu values: 8192 (8 vCPU)

Between 32768 (32 GB) and 122880 (120 GB) in increments of 8192 (8 GB) - Available cpu values: 16384 (16 vCPU)

This default is set in the underlying FargateTaskDefinition construct.

minHealthyPercentoptionalnumbermin_healthy_percentoptionalint | floatminHealthyPercentoptionalNumberMinHealthyPercentoptionaldoubleMinHealthyPercentoptional*float64#
The minimum number of tasks, specified as a percentage of the Amazon ECS service's DesiredCount value, that must continue to run and remain healthy during a deployment.

Default: 0 if daemon, otherwise 50

openListeneroptionalbooleanopen_listeneroptionalboolopenListeneroptionalBooleanOpenListeneroptionalboolOpenListeneroptional*bool#
Determines whether or not the Security Group for the Load Balancer's Listener will be open to all traffic by default.

Default: true -- The security group allows ingress from all IP addresses.

platformVersionoptionalFargatePlatformVersionplatform_versionoptionalFargatePlatformVersionplatformVersionoptionalFargatePlatformVersionPlatformVersionoptionalFargatePlatformVersionPlatformVersionoptionalFargatePlatformVersion= Latest#
The platform version on which to run your service.
notes

If one is not specified, the LATEST platform version is used by default. For more information, see AWS Fargate Platform Versions in the Amazon Elastic Container Service Developer Guide.

propagateTagsoptionalPropagatedTagSourcepropagate_tagsoptionalPropagatedTagSourcepropagateTagsoptionalPropagatedTagSourcePropagateTagsoptionalPropagatedTagSourcePropagateTagsoptionalPropagatedTagSource= none#
Specifies whether to propagate the tags from the task definition or the service to the tasks in the service.

Tags can only be propagated to the tasks within the service during service creation.

protocoloptionalApplicationProtocolprotocoloptionalApplicationProtocolprotocoloptionalApplicationProtocolProtocoloptionalApplicationProtocolProtocoloptionalApplicationProtocol#
The protocol for connections from clients to the load balancer.

Default: HTTP. If a certificate is specified, the protocol will be set by default to HTTPS.

The load balancer port is determined from the protocol (port 80 for HTTP, port 443 for HTTPS). If HTTPS, either a certificate or domain name and domain zone must also be specified.

protocolVersionoptionalApplicationProtocolVersionprotocol_versionoptionalApplicationProtocolVersionprotocolVersionoptionalApplicationProtocolVersionProtocolVersionoptionalApplicationProtocolVersionProtocolVersionoptionalApplicationProtocolVersion= ApplicationProtocolVersion.HTTP1#
The protocol version to use.
publicLoadBalanceroptionalbooleanpublic_load_balanceroptionalboolpublicLoadBalanceroptionalBooleanPublicLoadBalanceroptionalboolPublicLoadBalanceroptional*bool= true#
Determines whether the Load Balancer will be internet-facing.
Specifies whether the Route53 record should be a CNAME, an A record using the Alias feature or no record at all.

Default: ApplicationLoadBalancedServiceRecordType.ALIAS

This is useful if you need to work with DNS systems that do not support alias records.

redirectHTTPoptionalbooleanredirect_httpoptionalboolredirectHTTPoptionalBooleanRedirectHTTPoptionalboolRedirectHTTPoptional*bool= false#
Specifies whether the load balancer should redirect traffic on port 80 to the {@link listenerPort} to support HTTP->HTTPS redirects.

This is only valid if the protocol of the ALB is HTTPS.

runtimePlatformoptionalRuntimePlatformruntime_platformoptionalRuntimePlatformruntimePlatformoptionalRuntimePlatformRuntimePlatformoptionalRuntimePlatformRuntimePlatformoptionalRuntimePlatform#
The runtime platform of the task definition.

Default: If the property is undefined, operatingSystemFamily is LINUX and cpuArchitecture is X86_64

securityGroupsoptionalISecurityGroup[]security_groupsoptionaltyping.List[ISecurityGroup]securityGroupsoptionalList<ISecurityGroup>SecurityGroupsoptionalISecurityGroup[]SecurityGroupsoptional*[]ISecurityGroup#
The security groups to associate with the service.

Default: A new security group is created.

If you do not specify a security group, a new security group is created.

serviceNameoptionalstringservice_nameoptionalstrserviceNameoptionalStringServiceNameoptionalstringServiceNameoptional*string#
The name of the service.

Default: CloudFormation-generated name.

sslPolicyoptionalSslPolicyssl_policyoptionalSslPolicysslPolicyoptionalSslPolicySslPolicyoptionalSslPolicySslPolicyoptionalSslPolicy#
The security policy that defines which ciphers and protocols are supported by the ALB Listener.

Default: The recommended elastic load balancing security policy

targetProtocoloptionalApplicationProtocoltarget_protocoloptionalApplicationProtocoltargetProtocoloptionalApplicationProtocolTargetProtocoloptionalApplicationProtocolTargetProtocoloptionalApplicationProtocol= HTTP.#
The protocol for connections from the load balancer to the ECS tasks.

The default target port is determined from the protocol (port 80 for HTTP, port 443 for HTTPS).

taskDefinitionoptionalFargateTaskDefinitiontask_definitionoptionalFargateTaskDefinitiontaskDefinitionoptionalFargateTaskDefinitionTaskDefinitionoptionalFargateTaskDefinitionTaskDefinitionoptionalFargateTaskDefinition= none#
The task definition to use for tasks in the service. TaskDefinition or TaskImageOptions must be specified, but not both.

[disable-awslint:ref-via-interface]

taskImageOptionsoptionalApplicationLoadBalancedTaskImageOptionstask_image_optionsoptionalApplicationLoadBalancedTaskImageOptionstaskImageOptionsoptionalApplicationLoadBalancedTaskImageOptionsTaskImageOptionsoptionalApplicationLoadBalancedTaskImageOptionsTaskImageOptionsoptionalApplicationLoadBalancedTaskImageOptions= none#
The properties required to create a new task definition.

TaskDefinition or TaskImageOptions must be specified, but not both.

taskSubnetsoptionalSubnetSelectiontask_subnetsoptionalSubnetSelectiontaskSubnetsoptionalSubnetSelectionTaskSubnetsoptionalSubnetSelectionTaskSubnetsoptionalSubnetSelection#
The subnets to associate with the service.

Default: Public subnets if assignPublicIp is set, otherwise the first available one of Private, Isolated, Public, in that order.

vpcoptionalIVpcvpcoptionalIVpcvpcoptionalIVpcVpcoptionalIVpcVpcoptionalIVpc#
The VPC where the container instances will be launched or the elastic network interfaces (ENIs) will be deployed.

Default: uses the VPC defined in the cluster or creates a new VPC.

If a vpc is specified, the cluster construct should be omitted. Alternatively, you can omit both vpc and cluster.

Properties ​

assignPublicIpbooleanassign_public_ipboolassignPublicIpBooleanAssignPublicIpboolAssignPublicIp*boolrequired#
Determines whether the service will be assigned a public IP address.
certificatemay be undefinedICertificatecertificatemay be undefinedICertificatecertificatemay be undefinedICertificateCertificatemay be undefinedICertificateCertificatemay be undefinedICertificate#
Certificate Manager certificate to associate with the load balancer.
clusterIClusterclusterIClusterclusterIClusterClusterIClusterClusterIClusterrequired#
The cluster that hosts the service.
internalDesiredCountmay be undefinednumberinternal_desired_countmay be undefinedint | floatinternalDesiredCountmay be undefinedNumberInternalDesiredCountmay be undefineddoubleInternalDesiredCountmay be undefined*float64#
The desired number of instantiations of the task definition to keep running on the service.

The default is 1 for all new services and uses the existing services desired count when updating an existing service if one is not provided.

The listener for the service.
The Application Load Balancer for the service.
nodeNodenodeNodenodeNodeNodeNodeNodeNoderequired#
The tree node.
PROPERTY_INJECTION_IDstringproperty_injection_idstrPROPERTY_INJECTION_IDStringPROPERTY_INJECTION_IDstringPROPERTY_INJECTION_ID*stringrequiredstatic#
Uniquely identifies this class.
redirectListenermay be undefinedApplicationListenerredirect_listenermay be undefinedApplicationListenerredirectListenermay be undefinedApplicationListenerRedirectListenermay be undefinedApplicationListenerRedirectListenermay be undefinedApplicationListener#
The redirect listener for the service if redirectHTTP is enabled.
The Fargate service in this construct.
The target group for the service.
taskDefinitionFargateTaskDefinitiontask_definitionFargateTaskDefinitiontaskDefinitionFargateTaskDefinitionTaskDefinitionFargateTaskDefinitionTaskDefinitionFargateTaskDefinitionrequired#
The Fargate task definition in this construct.

Methods ​

isConstruct(x: any): boolean@staticmethod def is_construct(x: Any) -> boolpublic static Boolean isConstruct(Object x)public static bool IsConstruct(object x)func IsConstruct(X interface{}) *boolstatic#
Checks if `x` is a construct.
notes · 1 parameter · returns

Use this method instead of instanceof to properly detect Construct instances, even when the construct library is symlinked.

Explanation: in JavaScript, multiple copies of the constructs library on disk are seen as independent, completely different libraries. As a consequence, the class Construct in each copy of the constructs library is seen as a different class, and an instance of one class will not test as instanceof the other class. npm install will not create installations like this, but users may manually symlink construct libraries together or use a monorepo tool: in those cases, multiple copies of the constructs library can be accidentally installed, and instanceof will behave unpredictably. It is safest to avoid using instanceof, and using this type-testing method instead.

Parameters

  • xxxxX — Any object.

Returns: true if x is an object created from a class which extends Construct.

toString(): stringdef to_string(self, ) -> strpublic String toString()public string ToString()func ToString() *string#
Returns a string representation of this construct.
with(...mixins: IMixin[]): IConstructdef with(self, mixins: IMixin) -> IConstructpublic IConstruct with(IMixin mixins)public IConstruct With(IMixin mixins)func With(Mixins IMixin) IConstruct#
Applies one or more mixins to this construct.

Mixins are applied in order. The list of constructs is captured at the start of the call, so constructs added by a mixin will not be visited. Use multiple with() calls if subsequent mixins should apply to added constructs.

1 parameter · returns

Parameters

  • mixinsmixinsmixinsmixinsMixins — The mixins to apply.

Returns: This construct for chaining