func Update()

in aws-aps-rulegroupsnamespace/cmd/resource/resource.go [89:158]
63 lines of code
9 McCabe index (conditional complexity)

func Update(req handler.Request, prevModel *Model, currentModel *Model) (handler.ProgressEvent, error) {
	// contract test: contract_read_without_create
	if currentModel.Arn == nil {
		return handler.ProgressEvent{
			OperationStatus:  handler.Failed,
			Message:          "Invalid Update: Arn cannot be empty",
			HandlerErrorCode: cloudformation.HandlerErrorCodeNotFound,
			ResourceModel:    currentModel,
		}, nil
	}

	client := internal.NewAPS(req.Session)
	if _, ok := req.CallbackContext["Arn"]; ok {
		currentModel.Arn = aws.String(req.CallbackContext["Arn"].(string))
		return validateRuleGroupsNamespaceState(
			client,
			currentModel,
			prometheusservice.RuleGroupsNamespaceStatusCodeActive,
			"Update Complete")
	}

	_, workspaceID, err := internal.ParseARN(*currentModel.Arn)
	if err != nil {
		return handler.ProgressEvent{
			OperationStatus:  handler.Failed,
			Message:          "Invalid Read: invalid ARN format",
			HandlerErrorCode: cloudformation.HandlerErrorCodeNotFound,
			ResourceModel:    currentModel,
		}, nil
	}

	toAdd, toRemove := internal.StringMapDifference(tagsToStringMap(currentModel.Tags), tagsToStringMap(prevModel.Tags))
	if len(toRemove) > 0 {
		_, err = client.UntagResource(&prometheusservice.UntagResourceInput{
			ResourceArn: currentModel.Arn,
			TagKeys:     toRemove,
		})
		if err != nil {
			return internal.NewFailedEvent(err)
		}
	}

	if len(toAdd) > 0 {
		_, err = client.TagResource(&prometheusservice.TagResourceInput{
			ResourceArn: currentModel.Arn,
			Tags:        toAdd,
		})
		if err != nil {
			return internal.NewFailedEvent(err)
		}
	}

	_, err = client.
		PutRuleGroupsNamespace(&prometheusservice.PutRuleGroupsNamespaceInput{
			WorkspaceId: aws.String(workspaceID),
			Name:        currentModel.Name,
			Data:        []byte(*currentModel.Data),
		})
	if err != nil {
		return internal.NewFailedEvent(err)
	}

	return handler.ProgressEvent{
		OperationStatus:      handler.InProgress,
		Message:              "In Progress",
		ResourceModel:        currentModel,
		CallbackDelaySeconds: defaultCallbackSeconds,
		CallbackContext:      buildCallbackContext(currentModel),
	}, nil
}