substrate/cmd/ateapi/internal/controlapi/workflow_pause_test.go

// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package controlapi

import (
	"context"
	"testing"

	"github.com/agent-substrate/substrate/cmd/ateapi/internal/store/storetest"
	"github.com/agent-substrate/substrate/internal/resources"
	"github.com/agent-substrate/substrate/pkg/proto/ateapipb"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

// TestFinalizePausedStep_WorkerGone reproduces the scenario where the worker pod
// disappears from the DB during pause finalization, so the node it ran on is
// unknown.
//
// Old behavior: NodeVmsWithLocalSnapshots = []string{""}, which made the
// scheduler's node restriction search for a worker with node name "", never
// found, a permanent "no free workers available" on resume.
//
// Current behavior: NodeVmsWithLocalSnapshots is left nil, and the actor is
// crashed instead of left PAUSED, since a local snapshot with an unknown node
// can never be safely resumed.
func TestFinalizePausedStep_WorkerGone(t *testing.T) {
	st, cleanup := storetest.SetupTestStore(t)
	defer cleanup()

	ctx := context.Background()
	actorRef := resources.ActorRef{Atespace: "team-a", Name: "actor-1"}

	actor := &ateapipb.Actor{
		Metadata: &ateapipb.ResourceMetadata{Atespace: actorRef.Atespace, Name: actorRef.Name},
		Status:   ateapipb.Actor_STATUS_PAUSING,
		WorkerAssignment: &ateapipb.WorkerAssignment{
			WorkerNamespace: "default",
			WorkerPool:      "pool1",
			WorkerPod:       "worker-pod-1",
		},
		InProgressSnapshot: "snap-prefix",
	}
	if _, err := st.CreateActor(ctx, actor); err != nil {
		t.Fatalf("CreateActor: %v", err)
	}
	// Intentionally NOT creating the worker in store, simulates worker already gone.

	step := &FinalizePausedStep{store: st}
	input := &PauseInput{ActorRef: actorRef}
	state := &PauseState{}
	if err := step.Execute(ctx, input, state); err != nil {
		t.Fatalf("Execute: %v", err)
	}

	got, err := st.GetActor(ctx, actorRef)
	if err != nil {
		t.Fatalf("GetActor: %v", err)
	}

	if got.GetStatus() != ateapipb.Actor_STATUS_CRASHED {
		t.Errorf("status = %v, want CRASHED (node name unknown, cannot resume safely)", got.GetStatus())
	}
	for _, n := range got.GetLocalSnapshotInfo().GetNodeVmsWithLocalSnapshots() {
		if n == "" {
			t.Errorf("BUG: empty string in NodeVmsWithLocalSnapshots, the scheduler's node restriction would never match a real worker")
		}
	}

	state.Actor = got
	done, err := step.IsComplete(ctx, input, state)
	if err != nil {
		t.Fatalf("IsComplete: %v", err)
	}
	if !done {
		t.Error("IsComplete = false, want true once the actor is CRASHED and the worker is freed")
	}
}

// TestPauseActorWorkflow_RejectedAndIdempotentPaths covers the two
// short-circuit paths of the pause workflow: rejection by MarkPausingStep's
// CheckPrerequisite and the IsComplete idempotent fast-forward.
func TestPauseActorWorkflow_RejectedAndIdempotentPaths(t *testing.T) {
	tests := []struct {
		name       string
		seedStatus ateapipb.Actor_Status
		// wantErr true means PauseActor must fail with FailedPrecondition.
		wantErr bool
		// wantStatus is the stored status after the call.
		wantStatus ateapipb.Actor_Status
	}{
		{
			// Pausing a SUSPENDED actor is rejected by MarkPausingStep's
			// CheckPrerequisite and the actor's status is left untouched.
			name:       "not running rejected",
			seedStatus: ateapipb.Actor_STATUS_SUSPENDED,
			wantErr:    true,
			wantStatus: ateapipb.Actor_STATUS_SUSPENDED,
		},
		{
			// Pausing a PAUSED actor succeeds idempotently via IsComplete
			// fast-forward without calling atelet.
			name:       "already paused succeeds",
			seedStatus: ateapipb.Actor_STATUS_PAUSED,
			wantStatus: ateapipb.Actor_STATUS_PAUSED,
		},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			ctx := context.Background()
			st, cleanup := storetest.SetupTestStore(t)
			defer cleanup()
			w := newTestActorWorkflow(t, st, "ns", "tmpl1")

			seedWorkflowActor(t, ctx, st, resources.ActorRef{Atespace: "team-a", Name: "id1"}, "ns", "tmpl1", tc.seedStatus)

			actor, err := w.PauseActor(ctx, resources.ActorRef{Atespace: "team-a", Name: "id1"})
			if tc.wantErr {
				if got := status.Code(err); got != codes.FailedPrecondition {
					t.Fatalf("status.Code(err) = %v, want %v (err: %v)", got, codes.FailedPrecondition, err)
				}
			} else {
				if err != nil {
					t.Fatalf("PauseActor failed: %v", err)
				}
				if actor.GetStatus() != tc.wantStatus {
					t.Errorf("returned status = %v, want %v", actor.GetStatus(), tc.wantStatus)
				}
			}

			got, err := st.GetActor(ctx, resources.ActorRef{Atespace: "team-a", Name: "id1"})
			if err != nil {
				t.Fatalf("GetActor failed: %v", err)
			}
			if got.GetStatus() != tc.wantStatus {
				t.Errorf("stored status = %v, want %v", got.GetStatus(), tc.wantStatus)
			}
		})
	}
}

// TestPauseSteps_CheckPrerequisite verifies each pause step's CheckPrerequisite
// against every actor status: nil for the step's allowed statuses,
// FailedPrecondition for all others.
func TestPauseSteps_CheckPrerequisite(t *testing.T) {
	tests := []struct {
		name string
		step WorkflowStep[*PauseInput, *PauseState]
		// allowed lists the statuses CheckPrerequisite accepts; nil means
		// every status is accepted.
		allowed map[ateapipb.Actor_Status]bool
	}{
		{
			// Loading has no prerequisite: it is allowed from every status.
			name:    "LoadActorForPauseStep",
			step:    &LoadActorForPauseStep{},
			allowed: nil,
		},
		{
			// Pausing is allowed only from RUNNING.
			name: "MarkPausingStep",
			step: &MarkPausingStep{},
			allowed: map[ateapipb.Actor_Status]bool{
				ateapipb.Actor_STATUS_RUNNING: true,
			},
		},
		{
			// The checkpoint call is allowed only from PAUSING (PAUSED is
			// fast-forwarded by IsComplete).
			name: "CallAteletPauseStep",
			step: &CallAteletPauseStep{},
			allowed: map[ateapipb.Actor_Status]bool{
				ateapipb.Actor_STATUS_PAUSING: true,
			},
		},
		{
			// Finalizing is allowed only from PAUSING: a persisted PAUSED
			// actor always has its worker pod fields cleared and is
			// fast-forwarded by IsComplete.
			name: "FinalizePausedStep",
			step: &FinalizePausedStep{},
			allowed: map[ateapipb.Actor_Status]bool{
				ateapipb.Actor_STATUS_PAUSING: true,
			},
		},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			ctx := context.Background()
			for _, st := range allActorStatuses {
				// The worker assignment is populated so CallAteletPauseStep's
				// missing-worker crash branch is not taken; this test only
				// verifies status gating.
				err := tc.step.CheckPrerequisite(ctx, &PauseInput{ActorRef: resources.ActorRef{Name: "id1"}}, &PauseState{Actor: &ateapipb.Actor{Status: st, WorkerAssignment: &ateapipb.WorkerAssignment{WorkerNamespace: "ns", WorkerPool: "pool", WorkerPod: "worker-1"}}})
				assertPrerequisiteResult(t, st, err, tc.allowed == nil || tc.allowed[st])
			}
		})
	}
}

func TestCallAteletPauseStep_DanglingWorkerDoesNotRecordPhantomSnapshot(t *testing.T) {
	tests := []struct {
		name         string
		prevSnapshot *ateapipb.ObjectRef
	}{
		{
			name:         "keeps previous snapshot",
			prevSnapshot: &ateapipb.ObjectRef{Atespace: "team-a", Name: "prev"},
		},
		{
			name:         "stays nil without previous snapshot",
			prevSnapshot: nil,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			ctx := context.Background()
			persistence := newTestPersistence(t)

			actor := &ateapipb.Actor{
				Metadata: &ateapipb.ResourceMetadata{Atespace: "team-a", Name: "actor-1"},
				Status:   ateapipb.Actor_STATUS_PAUSING,
				WorkerAssignment: &ateapipb.WorkerAssignment{
					WorkerNamespace: "worker-ns",
					WorkerPool:      "pool",
					WorkerPod:       "pod-gone",
				},
				InProgressSnapshot: "actor-1-never-written",
				LatestSnapshot:     tt.prevSnapshot,
			}
			created, err := persistence.CreateActor(ctx, actor)
			if err != nil {
				t.Fatalf("CreateActor: %v", err)
			}

			step := &CallAteletPauseStep{store: persistence, dialer: newDanglingDialer()}
			input := &PauseInput{ActorRef: resources.ActorRef{Atespace: "team-a", Name: "actor-1"}}
			if err := step.Execute(ctx, input, &PauseState{Actor: created}); err == nil {
				t.Fatal("Execute: want error for dangling worker, got nil")
			}

			stored, err := persistence.GetActor(ctx, resources.ActorRef{Atespace: "team-a", Name: "actor-1"})
			if err != nil {
				t.Fatalf("GetActor: %v", err)
			}
			if stored.GetStatus() != ateapipb.Actor_STATUS_CRASHED {
				t.Errorf("status = %v, want CRASHED", stored.GetStatus())
			}
			if got := stored.GetInProgressSnapshot(); got != "actor-1-never-written" {
				t.Errorf("InProgressSnapshot = %q, want preserved for debugging", got)
			}
			if tt.prevSnapshot == nil {
				if stored.GetLatestSnapshot() != nil {
					t.Errorf("LatestSnapshot = %v, want nil", stored.GetLatestSnapshot())
				}
			} else if got, want := stored.GetLatestSnapshot().GetName(), tt.prevSnapshot.GetName(); got != want {
				t.Errorf("LatestSnapshot name = %q, want %q", got, want)
			}
		})
	}
}

// TestPauseActor_CrashesWhenPausingActorMissingWorkerPod verifies that a
// PAUSING actor with no worker pod recorded is moved to CRASHED by
// CallAteletPauseStep's prerequisite check and the pause fails with
// FailedPrecondition.
func TestPauseActor_CrashesWhenPausingActorMissingWorkerPod(t *testing.T) {
	ctx := context.Background()
	st, cleanup := storetest.SetupTestStore(t)
	defer cleanup()
	w := newTestActorWorkflow(t, st, "ns", "tmpl1")

	seedWorkflowActor(t, ctx, st, resources.ActorRef{Atespace: "team-a", Name: "id1"}, "ns", "tmpl1", ateapipb.Actor_STATUS_PAUSING)

	_, err := w.PauseActor(ctx, resources.ActorRef{Atespace: "team-a", Name: "id1"})
	if got := status.Code(err); got != codes.FailedPrecondition {
		t.Fatalf("status.Code(err) = %v, want %v (err: %v)", got, codes.FailedPrecondition, err)
	}

	got, err := st.GetActor(ctx, resources.ActorRef{Atespace: "team-a", Name: "id1"})
	if err != nil {
		t.Fatalf("GetActor failed: %v", err)
	}
	if got.GetStatus() != ateapipb.Actor_STATUS_CRASHED {
		t.Errorf("stored status = %v, want %v", got.GetStatus(), ateapipb.Actor_STATUS_CRASHED)
	}
}