# QueueProcessingEc2Service

Class to create a queue processing EC2 service.

Extends: Construct › QueueProcessingServiceBase › QueueProcessingEc2Service
Implements: IConstruct, IDependable

- Source: [`aws-ecs-patterns/lib/ecs/queue-processing-ecs-service.ts`](https://github.com/aws/aws-cdk/blob/v2.274.0/packages/aws-cdk-lib/aws-ecs-patterns/lib/ecs/queue-processing-ecs-service.ts#L95)
- Type last changed: v2.116.0 · 22 Dec 2023

## Example

```ts
declare const cluster: ecs.Cluster;
const queueProcessingEc2Service = new ecsPatterns.QueueProcessingEc2Service(this, 'Service', {
  cluster,
  memoryLimitMiB: 1024,
  image: ecs.ContainerImage.fromRegistry('test'),
  command: ["-c", "4", "amazon.com"],
  enableLogging: false,
  desiredTaskCount: 2,
  environment: {
    TEST_ENVIRONMENT_VARIABLE1: "test environment variable 1 value",
    TEST_ENVIRONMENT_VARIABLE2: "test environment variable 2 value",
  },
  maxScalingCapacity: 5,
  containerName: 'test',
  minHealthyPercent: 100,
});
```

## Initializer

```ts
new QueueProcessingEc2Service(scope: Construct, id: string, props?: QueueProcessingEc2ServiceProps)
```

## Construct Props

- `capacityProviderStrategies`: [CapacityProviderStrategy](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.CapacityProviderStrategy.html)[] = undefined — A list of Capacity Provider strategies used to place a service.

- `circuitBreaker`: [DeploymentCircuitBreaker](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.DeploymentCircuitBreaker.html) = disabled — Whether to enable the deployment circuit breaker.

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

- `cluster`: [ICluster](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.ICluster.html) — 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.

- `command`: string[] — The command that is passed to the container.

  **Default:** CMD value built into container image.

  If you provide a shell command as a single string, you have to quote command-line arguments.

- `containerName`: string = QueueProcessingContainer — Optional name for the container added.

- `cooldown`: [Duration](/cdk/api/v2/docs/aws-cdk-lib.Duration.html) — Grace period after scaling activity in seconds.

  **Default:** 300 seconds

  Subsequent scale outs during the cooldown period are squashed so that only
  the biggest scale out happens.

  Subsequent scale ins during the cooldown period are ignored.

- `cpu`: number = none — The number of cpu units used by the task.

  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

  This default is set in the underlying FargateTaskDefinition construct.

- `cpuTargetUtilizationPercent`: number = 50 — The target CPU utilization percentage for CPU based scaling strategy when enabled.

- `deploymentController`: [DeploymentController](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.DeploymentController.html) — Specifies which deployment controller to use for the service.

  **Default:** Rolling update (ECS)

  For more information, see
  [Amazon ECS Deployment Types](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/deployment-types.html)

- `disableCpuBasedScaling`: boolean = false — Flag to disable CPU based auto scaling strategy on the service.

- `enableECSManagedTags`: boolean = false — Specifies whether to enable Amazon ECS managed tags for the tasks within the service.

  For more information, see
  [Tagging Your Amazon ECS Resources](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-using-tags.html)

- `enableExecuteCommand`: boolean = false — Whether ECS Exec should be enabled.

- `enableLogging`: boolean = true — Flag to indicate whether to enable logging.

- `environment`: { [key: string]: string } — The environment variables to pass to the container.

  **Default:** 'QUEUE_NAME: queue.queueName'

  The variable `QUEUE_NAME` with value `queue.queueName` will
  always be passed.

- `family`: string — The name of a family that the task definition is registered to.

  **Default:** Automatically generated name.

  A family groups multiple versions of a task definition.

- `gpuCount`: number — Gpu count for container in task definition.

  **Default:** No GPUs assigned.

  Set this if you want to use gpu based instances.

- `image`: [ContainerImage](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.ContainerImage.html) — The image used to start a container.

  **Default:** the image of the task definition is used for Fargate, required otherwise

  For `QueueProcessingFargateService`, either `image` or `taskDefinition` must be specified, but not both.
  For `QueueProcessingEc2Service`, `image` is required.

- `logDriver`: [LogDriver](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.LogDriver.html) — The log driver to use.

  **Default:** AwsLogDriver if enableLogging is true

- `maxHealthyPercent`: number — 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:** default from underlying service.

- `maxReceiveCount`: number = 3 — The maximum number of times that a message can be received by consumers.

  When this value is exceeded for a message the message will be automatically sent to the Dead Letter Queue.

  If the queue construct is specified, maxReceiveCount should be omitted.

- `maxScalingCapacity`: number = 2 — Maximum capacity to scale to.

- `memoryLimitMiB`: number — The hard limit (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.

  At least one of memoryLimitMiB and memoryReservationMiB is required for non-Fargate services.

- `memoryReservationMiB`: number — The soft limit (in MiB) of memory to reserve for the container.

  **Default:** No memory reserved.

  When system memory is under contention, Docker attempts to keep the
  container memory within the limit. If the container requires more memory,
  it can consume up to the value specified by the Memory property or all of
  the available memory on the container instance—whichever comes first.

  At least one of memoryLimitMiB and memoryReservationMiB is required for non-Fargate services.

- `minHealthyPercent`: number — 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:** default from underlying service.

- `minScalingCapacity`: number = 1 — Minimum capacity to scale to.

- `placementConstraints`: [PlacementConstraint](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.PlacementConstraint.html)[] — The placement constraints to use for tasks in the service.

  **Default:** No constraints.

  For more information, see
  [Amazon ECS Task Placement Constraints](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-placement-constraints.html).

- `placementStrategies`: [PlacementStrategy](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.PlacementStrategy.html)[] — The placement strategies to use for tasks in the service.

  **Default:** No strategies.

  For more information, see
  [Amazon ECS Task Placement Strategies](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-placement-strategies.html).

- `propagateTags`: [PropagatedTagSource](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.PropagatedTagSource.html) = 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.

- `queue`: [IQueue](/cdk/api/v2/docs/aws-cdk-lib.aws_sqs.IQueue.html) — A queue for which to process items from.

  **Default:** 'SQSQueue with CloudFormation-generated name'

  If specified and this is a FIFO queue, the queue name must end in the string '.fifo'. See
  [CreateQueue](https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_CreateQueue.html)

- `retentionPeriod`: [Duration](/cdk/api/v2/docs/aws-cdk-lib.Duration.html) = Duration.days(14) — The number of seconds that Dead Letter Queue retains a message.

  If the queue construct is specified, retentionPeriod should be omitted.

- `scalingSteps`: [ScalingInterval](/cdk/api/v2/docs/aws-cdk-lib.aws_applicationautoscaling.ScalingInterval.html)[] — The intervals for scaling based on the SQS queue's ApproximateNumberOfMessagesVisible metric.

  **Default:** [{ upper: 0, change: -1 },{ lower: 100, change: +1 },{ lower: 500, change: +5 }]

  Maps a range of metric values to a particular scaling behavior. See
  [Simple and Step Scaling Policies for Amazon EC2 Auto Scaling](https://docs.aws.amazon.com/autoscaling/ec2/userguide/as-scaling-simple-step.html)

- `secrets`: { [key: string]: [Secret](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.Secret.html) } — The secret to expose to the container as an environment variable.

  **Default:** No secret environment variables.

- `serviceName`: string — The name of the service.

  **Default:** CloudFormation-generated name.

- `visibilityTimeout`: [Duration](/cdk/api/v2/docs/aws-cdk-lib.Duration.html) = Duration.seconds(30) — Timeout of processing a single message.

  After dequeuing, the processor has this much time to handle the message and delete it from the queue
  before it becomes visible again for dequeueing by another processor. Values must be between 0 and (12 hours).

  If the queue construct is specified, visibilityTimeout should be omitted.

- `vpc`: [IVpc](/cdk/api/v2/docs/aws-cdk-lib.aws_ec2.IVpc.html) — 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

- `cluster`: [ICluster](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.ICluster.html) (required) — The cluster where your service will be deployed.

- `deadLetterQueue`: [IQueue](/cdk/api/v2/docs/aws-cdk-lib.aws_sqs.IQueue.html) — The dead letter queue for the primary SQS queue.

- `environment`: { [key: string]: string } (required) — Environment variables that will include the queue name.

- `logDriver`: [LogDriver](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.LogDriver.html) — The AwsLogDriver to use for logging if logging is enabled.

- `maxCapacity`: number (required) — The maximum number of instances for autoscaling to scale up to.

- `minCapacity`: number (required) — The minimum number of instances for autoscaling to scale down to.

- `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) (required) — The tree node.

- `scalingSteps`: [ScalingInterval](/cdk/api/v2/docs/aws-cdk-lib.aws_applicationautoscaling.ScalingInterval.html)[] (required) — The scaling interval for autoscaling based off an SQS Queue size.

- `secrets`: { [key: string]: [Secret](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.Secret.html) } — The secret environment variables.

- `service`: [Ec2Service](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.Ec2Service.html) (required) — The EC2 service in this construct.

- `sqsQueue`: [IQueue](/cdk/api/v2/docs/aws-cdk-lib.aws_sqs.IQueue.html) (required) — The SQS queue that the service will process from.

- `taskDefinition`: [Ec2TaskDefinition](/cdk/api/v2/docs/aws-cdk-lib.aws_ecs.Ec2TaskDefinition.html) (required) — The EC2 task definition in this construct.

## Methods

- `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct.

  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**

  - `x` — Any object.

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

- `toString(): string` — Returns a string representation of this construct.

- `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.

  **Parameters**

  - `mixins` — The mixins to apply.

  **Returns:** This construct for chaining
