tasks/service/worker/deletenamespace/workflow.go

package deletenamespace

import (
	"fmt"
	"slices"
	"time"

	enumspb "go.temporal.io/api/enums/v1"
	"go.temporal.io/sdk/log"
	"go.temporal.io/sdk/temporal"
	"go.temporal.io/sdk/workflow"
	"go.temporal.io/server/common/log/tag"
	"go.temporal.io/server/common/namespace"
	"go.temporal.io/server/common/primitives"
	"go.temporal.io/server/service/worker/deletenamespace/deleteexecutions"
	"go.temporal.io/server/service/worker/deletenamespace/errors"
	"go.temporal.io/server/service/worker/deletenamespace/reclaimresources"
)

const (
	WorkflowName = "temporal-sys-delete-namespace-workflow"
)

type (
	DeleteNamespaceWorkflowParams struct {
		// One of NamespaceID or Namespace must be provided.
		NamespaceID namespace.ID
		Namespace   namespace.Name

		// NamespaceDeleteDelay indicates duration for how long namespace stays in database
		// after all namespace resources (i.e. workflow executions) are deleted.
		// Default is 0, means, namespace will be deleted immediately.
		NamespaceDeleteDelay time.Duration

		DeleteExecutionsConfig deleteexecutions.DeleteExecutionsConfig
	}

	DeleteNamespaceWorkflowResult struct {
		DeletedNamespaceID namespace.ID
		DeletedNamespace   namespace.Name
	}
)

var (
	localRetryPolicy = &temporal.RetryPolicy{
		InitialInterval: 1 * time.Second,
		MaximumInterval: 10 * time.Second,
	}

	reclaimResourcesWorkflowRetryPolicy = &temporal.RetryPolicy{
		InitialInterval: 60 * time.Second,
		// ReclaimResourcesWorkflow will try to delete workflow executions (call `DeleteWorkflowExecution` and wait for all executions to be deleted) 3 times.
		// If there are still executions left, ReclaimResourcesWorkflow fails, and needs to be restarted manually (this indicates some serious problems with transfer/visibility task processing).
		MaximumAttempts: 3,
	}

	localActivityOptions = workflow.LocalActivityOptions{
		RetryPolicy:            localRetryPolicy,
		StartToCloseTimeout:    30 * time.Second,
		ScheduleToCloseTimeout: 5 * time.Minute,
	}

	reclaimResourcesWorkflowOptions = workflow.ChildWorkflowOptions{
		RetryPolicy: reclaimResourcesWorkflowRetryPolicy,
		// Important: this is required to make sure the child workflow is not terminated when delete namespace workflow is completed.
		ParentClosePolicy: enumspb.PARENT_CLOSE_POLICY_ABANDON,
		// If the client is calling DeleteNamespace API again while ReclaimResourcesWorkflow is running, it might want to terminate existing run and start a new run.
		WorkflowIDReusePolicy: enumspb.WORKFLOW_ID_REUSE_POLICY_TERMINATE_IF_RUNNING,
	}
)

func validateParams(params *DeleteNamespaceWorkflowParams) error {
	if params.Namespace.IsEmpty() && params.NamespaceID.IsEmpty() {
		return errors.NewInvalidArgument("namespace or namespace ID is required", nil)
	}
	if !params.Namespace.IsEmpty() && !params.NamespaceID.IsEmpty() {
		return errors.NewInvalidArgument("only one of namespace or namespace ID must be set", nil)
	}
	params.DeleteExecutionsConfig.ApplyDefaults()
	return nil
}

func validateNamespace(ctx workflow.Context, nsInfo getNamespaceInfoResult) error {

	if nsInfo.Namespace == primitives.SystemLocalNamespace || nsInfo.NamespaceID == primitives.SystemNamespaceID {
		return errors.NewFailedPrecondition("unable to delete system namespace", nil)
	}

	// Prevent namespace deletion if namespace is passive in the current cluster,
	// because then WF executions will keep coming from the active cluster and
	// namespace will never be deleted (ReclaimResourcesWorkflow will fail).
	if slices.Contains(nsInfo.Clusters, nsInfo.CurrentCluster) && nsInfo.ActiveCluster != nsInfo.CurrentCluster {
		return errors.NewFailedPrecondition(fmt.Sprintf("namespace %[1]s is passive in current cluster %[2]s: remove cluster %[2]s from cluster list or make namespace active in this cluster and retry", nsInfo.Namespace, nsInfo.CurrentCluster), nil)
	}

	// NOTE: there is very little chance that another cluster is added after the check above,
	// but before namespace is marked as deleted below.

	var la *localActivities

	ctx1 := workflow.WithLocalActivityOptions(ctx, localActivityOptions)
	err := workflow.ExecuteLocalActivity(ctx1, la.ValidateProtectedNamespacesActivity, nsInfo.Namespace).Get(ctx, nil)
	if err != nil {
		return err
	}

	ctx2 := workflow.WithLocalActivityOptions(ctx, localActivityOptions)
	err = workflow.ExecuteLocalActivity(ctx2, la.ValidateNexusEndpointsActivity, nsInfo.NamespaceID, nsInfo.Namespace).Get(ctx, nil)
	if err != nil {
		return err
	}

	return nil
}

func DeleteNamespaceWorkflow(ctx workflow.Context, params DeleteNamespaceWorkflowParams) (DeleteNamespaceWorkflowResult, error) {
	logger := log.With(
		workflow.GetLogger(ctx),
		tag.WorkflowType(WorkflowName),
		tag.WorkflowNamespace(params.Namespace.String()),
		tag.WorkflowNamespaceID(params.NamespaceID.String()))

	logger.Info("Workflow started.")

	var result DeleteNamespaceWorkflowResult

	if err := validateParams(&params); err != nil {
		return result, err
	}

	ctx = workflow.WithTaskQueue(ctx, primitives.DeleteNamespaceActivityTQ)

	var la *localActivities

	// Step 1. Get namespace info.
	ctx1 := workflow.WithLocalActivityOptions(ctx, localActivityOptions)
	var namespaceInfo getNamespaceInfoResult
	err := workflow.ExecuteLocalActivity(ctx1, la.GetNamespaceInfoActivity, params.NamespaceID, params.Namespace).Get(ctx, &namespaceInfo)
	if err != nil {
		return result, err
	}

	// Step 1.1. Validate namespace.
	if err = validateNamespace(ctx, namespaceInfo); err != nil {
		return result, err
	}

	params.Namespace = namespaceInfo.Namespace
	params.NamespaceID = namespaceInfo.NamespaceID

	// Step 2. Mark namespace as deleted.
	ctx2 := workflow.WithLocalActivityOptions(ctx, localActivityOptions)
	err = workflow.ExecuteLocalActivity(ctx2, la.MarkNamespaceDeletedActivity, params.Namespace).Get(ctx, nil)
	if err != nil {
		return result, err
	}

	result.DeletedNamespaceID = params.NamespaceID

	// Step 3. Rename namespace.
	ctx3 := workflow.WithLocalActivityOptions(ctx, localActivityOptions)
	err = workflow.ExecuteLocalActivity(ctx3, la.GenerateDeletedNamespaceNameActivity, params.NamespaceID, params.Namespace).Get(ctx, &result.DeletedNamespace)
	if err != nil {
		return result, err
	}

	ctx31 := workflow.WithLocalActivityOptions(ctx, localActivityOptions)
	err = workflow.ExecuteLocalActivity(ctx31, la.RenameNamespaceActivity, params.Namespace, result.DeletedNamespace).Get(ctx, nil)
	if err != nil {
		return result, err
	}

	// Step 4. Reclaim workflow resources asynchronously.
	ctx4 := workflow.WithChildOptions(ctx, reclaimResourcesWorkflowOptions)
	ctx4 = workflow.WithWorkflowID(ctx4, fmt.Sprintf("%s/%s", reclaimresources.WorkflowName, result.DeletedNamespace))

	reclaimResourcesFuture := workflow.ExecuteChildWorkflow(ctx4, reclaimresources.ReclaimResourcesWorkflow, reclaimresources.ReclaimResourcesParams{
		DeleteExecutionsParams: deleteexecutions.DeleteExecutionsParams{
			Namespace:   result.DeletedNamespace,
			NamespaceID: params.NamespaceID,
			Config:      params.DeleteExecutionsConfig,
		},
		NamespaceDeleteDelay: params.NamespaceDeleteDelay,
	})
	var reclaimResourcesExecution workflow.Execution
	if err = reclaimResourcesFuture.GetChildWorkflowExecution().Get(ctx, &reclaimResourcesExecution); err != nil {
		logger.Error("Child workflow error.", tag.Error(err))
		return result, err
	}
	logger.Info("Child workflow executed successfully.", tag.NewStringTag("wf-child-type", reclaimresources.WorkflowName))

	logger.Info("Workflow finished successfully.")
	return result, nil
}