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run_task

Operation

run_task async

run_task(input: RunTaskInput, plugins: list[Plugin] | None = None) -> RunTaskOutput

Starts a new task using the specified task definition.

Note

On March 21, 2024, a change was made to resolve the task definition revision before authorization. When a task definition revision is not specified, authorization will occur using the latest revision of a task definition.

Note: Amazon Elastic Inference (EI) is no longer available to customers.

You can allow Amazon ECS to place tasks for you, or you can customize how Amazon ECS places tasks using placement constraints and placement strategies. For more information, see Scheduling Tasks in the Amazon Elastic Container Service Developer Guide.

Alternatively, you can use StartTask to use your own scheduler or place tasks manually on specific container instances.

You can attach Amazon EBS volumes to Amazon ECS tasks by configuring the volume when creating or updating a service. For more information, see Amazon EBS volumes in the Amazon Elastic Container Service Developer Guide.

The Amazon ECS API follows an eventual consistency model. This is because of the distributed nature of the system supporting the API. This means that the result of an API command you run that affects your Amazon ECS resources might not be immediately visible to all subsequent commands you run. Keep this in mind when you carry out an API command that immediately follows a previous API command.

To manage eventual consistency, you can do the following:

  • Confirm the state of the resource before you run a command to modify it. Run the DescribeTasks command using an exponential backoff algorithm to ensure that you allow enough time for the previous command to propagate through the system. To do this, run the DescribeTasks command repeatedly, starting with a couple of seconds of wait time and increasing gradually up to five minutes of wait time.

  • Add wait time between subsequent commands, even if the DescribeTasks command returns an accurate response. Apply an exponential backoff algorithm starting with a couple of seconds of wait time, and increase gradually up to about five minutes of wait time.

If you get a ConflictException error, the RunTask request could not be processed due to conflicts. The provided clientToken is already in use with a different RunTask request. The resourceIds are the existing task ARNs which are already associated with the clientToken.

To fix this issue:

  • Run RunTask with a unique clientToken.

  • Run RunTask with the clientToken and the original set of parameters

If you get a ClientExceptionerror, the RunTask could not be processed because you use managed scaling and there is a capacity error because the quota of tasks in the PROVISIONING per cluster has been reached. For information about the service quotas, see Amazon ECS service quotas.

Parameters:

Name Type Description Default
input RunTaskInput

An instance of RunTaskInput.

required
plugins list[Plugin] | None

A list of callables that modify the configuration dynamically. Changes made by these plugins only apply for the duration of the operation execution and will not affect any other operation invocations.

None

Returns:

Type Description
RunTaskOutput

An instance of RunTaskOutput.

Input

RunTaskInput dataclass

Bases: _SerdeShape

Attributes

capacity_provider_strategy class-attribute instance-attribute
capacity_provider_strategy: list[CapacityProviderStrategyItem] | None = ...

The capacity provider strategy to use for the task.

Note

If you want to use Amazon ECS Managed Instances, you must use the capacityProviderStrategy request parameter and omit the launchType request parameter.

If a capacityProviderStrategy is specified, the launchType parameter must be omitted. If no capacityProviderStrategy or launchType is specified, the defaultCapacityProviderStrategy for the cluster is used.

When you use cluster auto scaling, you must specify capacityProviderStrategy and not launchType.

A capacity provider strategy can contain a maximum of 20 capacity providers.

client_token class-attribute instance-attribute
client_token: str | None = ...

An identifier that you provide to ensure the idempotency of the request. It must be unique and is case sensitive. Up to 64 characters are allowed. The valid characters are characters in the range of 33-126, inclusive. For more information, see Ensuring idempotency.

This field is autopopulated if not provided.

cluster class-attribute instance-attribute
cluster: str | None = ...

The short name or full Amazon Resource Name (ARN) of the cluster to run your task on. If you do not specify a cluster, the default cluster is assumed.

Each account receives a default cluster the first time you use the service, but you may also create other clusters.

count class-attribute instance-attribute
count: int | None = ...

The number of instantiations of the specified task to place on your cluster. You can specify up to 10 tasks for each call.

enable_ecs_managed_tags class-attribute instance-attribute
enable_ecs_managed_tags: bool = ...

Specifies whether to use Amazon ECS managed tags for the task. For more information, see Tagging Your Amazon ECS Resources in the Amazon Elastic Container Service Developer Guide.

enable_execute_command class-attribute instance-attribute
enable_execute_command: bool = ...

Determines whether to use the execute command functionality for the containers in this task. If true, this enables execute command functionality on all containers in the task.

If true, then the task definition must have a task role, or you must provide one as an override.

group class-attribute instance-attribute
group: str | None = ...

The name of the task group to associate with the task. The default value is the family name of the task definition (for example, family:my-family-name).

launch_type class-attribute instance-attribute
launch_type: str | None = ...

The infrastructure to run your standalone task on. For more information, see Amazon ECS launch types in the Amazon Elastic Container Service Developer Guide.

Note

If you want to use Amazon ECS Managed Instances, you must use the capacityProviderStrategy request parameter and omit the launchType request parameter.

The FARGATE launch type runs your tasks on Fargate On-Demand infrastructure.

Note

Fargate Spot infrastructure is available for use but a capacity provider strategy must be used. For more information, see Fargate capacity providers in the Amazon ECS Developer Guide.

The EC2 launch type runs your tasks on Amazon EC2 instances registered to your cluster.

The EXTERNAL launch type runs your tasks on your on-premises server or virtual machine (VM) capacity registered to your cluster.

A task can use either a launch type or a capacity provider strategy. If a launchType is specified, the capacityProviderStrategy parameter must be omitted.

When you use cluster auto scaling, you must specify capacityProviderStrategy and not launchType.

network_configuration class-attribute instance-attribute
network_configuration: NetworkConfiguration | None = ...

The network configuration for the task. This parameter is required for task definitions that use the awsvpc network mode to receive their own elastic network interface, and it isn't supported for other network modes. For more information, see Task networking in the Amazon Elastic Container Service Developer Guide.

overrides class-attribute instance-attribute
overrides: TaskOverride | None = ...

A list of container overrides in JSON format that specify the name of a container in the specified task definition and the overrides it should receive. You can override the default command for a container (that's specified in the task definition or Docker image) with a command override. You can also override existing environment variables (that are specified in the task definition or Docker image) on a container or add new environment variables to it with an environment override.

A total of 8192 characters are allowed for overrides. This limit includes the JSON formatting characters of the override structure.

placement_constraints class-attribute instance-attribute
placement_constraints: list[PlacementConstraint] | None = ...

An array of placement constraint objects to use for the task. You can specify up to 10 constraints for each task (including constraints in the task definition and those specified at runtime).

placement_strategy class-attribute instance-attribute
placement_strategy: list[PlacementStrategy] | None = ...

The placement strategy objects to use for the task. You can specify a maximum of 5 strategy rules for each task.

platform_version class-attribute instance-attribute
platform_version: str | None = ...

The platform version the task uses. A platform version is only specified for tasks hosted on Fargate. If one isn't specified, the LATEST platform version is used. For more information, see Fargate platform versions in the Amazon Elastic Container Service Developer Guide.

propagate_tags class-attribute instance-attribute
propagate_tags: str | None = ...

Specifies whether to propagate the tags from the task definition to the task. If no value is specified, the tags aren't propagated. Tags can only be propagated to the task during task creation. To add tags to a task after task creation, use theTagResource API action.

Note

An error will be received if you specify the SERVICE option when running a task.

reference_id class-attribute instance-attribute
reference_id: str | None = ...

This parameter is only used by Amazon ECS. It is not intended for use by customers.

started_by class-attribute instance-attribute
started_by: str | None = ...

An optional tag specified when a task is started. For example, if you automatically trigger a task to run a batch process job, you could apply a unique identifier for that job to your task with the startedBy parameter. You can then identify which tasks belong to that job by filtering the results of a ListTasks call with the startedBy value. Up to 128 letters (uppercase and lowercase), numbers, hyphens (-), forward slash (/), and underscores (_) are allowed.

If a task is started by an Amazon ECS service, then the startedBy parameter contains the deployment ID of the service that starts it.

tags class-attribute instance-attribute
tags: list[Tag] | None = ...

The metadata that you apply to the task to help you categorize and organize them. Each tag consists of a key and an optional value, both of which you define.

The following basic restrictions apply to tags:

  • Maximum number of tags per resource - 50

  • For each resource, each tag key must be unique, and each tag key can have only one value.

  • Maximum key length - 128 Unicode characters in UTF-8

  • Maximum value length - 256 Unicode characters in UTF-8

  • If your tagging schema is used across multiple services and resources, remember that other services may have restrictions on allowed characters. Generally allowed characters are: letters, numbers, and spaces representable in UTF-8, and the following characters: + - = . _ : / @.

  • Tag keys and values are case-sensitive.

  • Do not use aws:, AWS:, or any upper or lowercase combination of such as a prefix for either keys or values as it is reserved for Amazon Web Services use. You cannot edit or delete tag keys or values with this prefix. Tags with this prefix do not count against your tags per resource limit.

task_definition class-attribute instance-attribute
task_definition: str | None = ...

The family and revision (family:revision) or full ARN of the task definition to run. If a revision isn't specified, the latest ACTIVE revision is used.

The full ARN value must match the value that you specified as the Resource of the principal's permissions policy.

When you specify a task definition, you must either specify a specific revision, or all revisions in the ARN.

To specify a specific revision, include the revision number in the ARN. For example, to specify revision 2, use arn:aws:ecs:us-east-1:111122223333:task-definition/TaskFamilyName:2.

To specify all revisions, use the wildcard (*) in the ARN. For example, to specify all revisions, use arn:aws:ecs:us-east-1:111122223333:task-definition/TaskFamilyName:*.

For more information, see Policy Resources for Amazon ECS in the Amazon Elastic Container Service Developer Guide.

volume_configurations class-attribute instance-attribute
volume_configurations: list[TaskVolumeConfiguration] | None = ...

The details of the volume that was configuredAtLaunch. You can configure the size, volumeType, IOPS, throughput, snapshot and encryption in TaskManagedEBSVolumeConfiguration. The name of the volume must match the name from the task definition.

Output

RunTaskOutput dataclass

Bases: _SerdeShape

Attributes

failures class-attribute instance-attribute
failures: list[Failure] | None = ...

Any failures associated with the call.

For information about how to address failures, see Service event messages and API failure reasons in the Amazon Elastic Container Service Developer Guide.

response_metadata class-attribute instance-attribute
response_metadata: ResponseMetadata = ...

Metadata about the response that produced this output. Use this to recover the request identifiers a service's support team needs in order to investigate a call. Members of the metadata are individually optional.

tasks class-attribute instance-attribute
tasks: list[Task] | None = ...

A full description of the tasks that were run. The tasks that were successfully placed on your cluster are described here.