Update the task definition of a fargate scheduled task in ECS cluster

Question

I have a pipeline setup to an ecs cluster in which I update the services' task definition and then launch a new deploy. E.g.:

# Update task definition
- aws ecs register-task-definition --cli-input-json file://aws/task-definition${TASK_SUFFIX}.json --region $AWS_DEFAULT_REGION
- TASK_REVISION=`aws ecs describe-task-definition --task-definition ${SERVICE_NAME}${TASK_SUFFIX} | egrep "revision" | tr "/" " " | awk '{print $2}' | sed 's/"$//'`

# Request service update:
- aws ecs update-service --service ${SERVICE_NAME} --cluster ${CLUSTER_NAME} --task-definition ${SERVICE_NAME}${TASK_SUFFIX}:${TASK_REVISION} --force-new-deployment

I have a scheduled task that uses the same task definition of a service, both using fargate. However, when I update my service's task definition, I have to manually update my scheduled task to the latest revision.

I would like to update my scheduled task's task definition to the latest revision whenever I update my service's task definition. Is it possible?

baku baku · Accepted Answer · 2020-05-10T18:11:20

so for me this is working

   aws events put-targets --cli-input-json file://.app_generic.json

app_generic.json

{
  "Rule": "rule--app--generic",
  "Targets": [
    {
      "Id": "app--generic",
      "Arn": "arn:aws:ecs:us-east-1:xxxxxxx:cluster/my-cluster",
      "RoleArn": "arn:aws:iam::xxxxxxx:role/ecsEventsRole",
      "EcsParameters": {
        "TaskDefinitionArn": "arn:aws:ecs:us-east-1:xxxxxxxx:task-definition/my-task-definitions",
        "TaskCount": 1,
        "LaunchType": "FARGATE",
        "NetworkConfiguration": {
          "awsvpcConfiguration": {
            "Subnets": [
              "subnet-xxxxx"
            ],
            "SecurityGroups": [
              "sg-xxxxxxx"
            ],
            "AssignPublicIp": "ENABLED"
          }
        },
        "PlatformVersion": "1.4.0"
      }
    }
  ]
}

Basically I have to re-put the rule, but by leaving out the revision number in TaskDefinitionArn, it's updated to the latest revision, while other container params (command, environment variables etc) persist. I suppose this is technically still 'manual', but the command can just be added after service update in CI/CD, bash script etc.

Update the task definition of a fargate scheduled task in ECS cluster

1 Answers