Propagate task definition tags through RegisterTaskDefinition

DescribeTaskDefinition now requests TAGS, and RegisterTaskDefinition
passes them through when registering the new revision. This keeps the
tags on existing task definitions (typically set by Terraform) intact
across ecs-tool deploys and run-task invocations.

This unblocks deploys against AWS accounts where an SCP enforces
mandatory tag keys on ecs:RegisterTaskDefinition: the new revision
inherits the tags from the previous one, so aws:TagKeys is populated
in the API request.

Behaviour for projects that don't tag their task definitions is
unchanged - DescribeTaskDefinition returns an empty Tags slice, and
the RegisterTaskDefinition call passes nil tags as before.

Author: teaguru

lib/deploy.go

@@ -81,6 +81,7 @@ func deployService(ctx log.Interface, cluster, imageTag string, imageTags []stri
 	// then describe the task definition to get a copy of it
 	describeTaskResult, err := svc.DescribeTaskDefinition(&ecs.DescribeTaskDefinitionInput{
 		TaskDefinition: describeResult.Services[0].TaskDefinition,
+		Include:        aws.StringSlice([]string{"TAGS"}),
 	})
 	if err != nil {
 		ctx.WithError(err).Error("Can't get task definition")
@@ -107,6 +108,7 @@ func deployService(ctx log.Interface, cluster, imageTag string, imageTags []stri
 		RequiresCompatibilities: taskDefinition.Compatibilities,
 		TaskRoleArn:             taskDefinition.TaskRoleArn,
 		Volumes:                 taskDefinition.Volumes,
+		Tags:                    describeTaskResult.Tags,
 	})
 	if err != nil {
 		ctx.WithError(err).Error("Can't register task definition")

lib/run.go

@@ -23,6 +23,7 @@ func RunTask(profile, cluster, service, taskDefinitionName, imageTag string, ima
 
 	describeResult, err := svc.DescribeTaskDefinition(&ecs.DescribeTaskDefinitionInput{
 		TaskDefinition: aws.String(taskDefinitionName),
+		Include:        aws.StringSlice([]string{"TAGS"}),
 	})
 	if err != nil {
 		ctx.WithError(err).Error("Can't get task definition")
@@ -67,6 +68,7 @@ func RunTask(profile, cluster, service, taskDefinitionName, imageTag string, ima
 		RequiresCompatibilities: taskDefinition.Compatibilities,
 		TaskRoleArn:             taskDefinition.TaskRoleArn,
 		Volumes:                 taskDefinition.Volumes,
+		Tags:                    describeResult.Tags,
 	})
 	if err != nil {
 		ctx.WithError(err).Error("Can't register task definition")

lib/runFargate.go

@@ -63,6 +63,7 @@ func RunFargate(profile, cluster, service, taskDefinitionName, imageTag string,
 
 	describeResult, err := svc.DescribeTaskDefinition(&ecs.DescribeTaskDefinitionInput{
 		TaskDefinition: aws.String(taskDefinitionName),
+		Include:        aws.StringSlice([]string{"TAGS"}),
 	})
 	if err != nil {
 		ctx.WithError(err).Error("Can't get task definition")
@@ -111,6 +112,7 @@ func RunFargate(profile, cluster, service, taskDefinitionName, imageTag string,
 		RequiresCompatibilities: taskDefinition.Compatibilities,
 		TaskRoleArn:             taskDefinition.TaskRoleArn,
 		Volumes:                 taskDefinition.Volumes,
+		Tags:                    describeResult.Tags,
 	})
 	if err != nil {
 		ctx.WithError(err).Error("Can't register task definition")