code: func (manager *metadataManager) parseMetadataAtContainerCreate(task *apitask.Task, containerName string) Metadata {
  	return Metadata{
  		cluster: manager.cluster,
  		taskMetadata: TaskMetadata{
  			containerName:          containerName,
  			taskARN:                task.Arn,
  			taskDefinitionFamily:   task.Family,
  			taskDefinitionRevision: task.Version,
  		},
  		containerInstanceARN:  manager.containerInstanceARN,
  		metadataStatus:        MetadataInitial,
  		availabilityZone:      manager.availabilityZone,
  		hostPublicIPv4Address: manager.hostPublicIPv4Address,
  	}
  }
docs: // parseMetadataAtContainerCreate gathers metadata from task and cluster configurations
  // then packages it for JSON Marshaling. We use this version to get data
  // available prior to container creation
  // Since we accept incomplete metadata fields, we should not return
  // errors here and handle them at this or the above stage.