feat: support durable task cancellation without foreign keys

sdk/go/worker_cancel_test.go

@@ -0,0 +1,42 @@
+package orbit
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/coder/websocket"
+)
+
+func TestCancellationNotificationAndExecutionBoundary(t *testing.T) {
+	r := workerTestRegistration(t)
+	r.CancellationNotifications = true
+	_, c := workerMock(t, r, func(ctx context.Context, c *websocket.Conn) {
+		body := workerTestBody(t, WorkerCancellation{TaskID: workerTestTask, AttemptID: workerTestAttempt, Epoch: 1, RequestedAt: time.Now().UTC()})
+		workerTestWrite(t, ctx, c, workerFrame{Type: "task.cancel", Body: body})
+		<-ctx.Done()
+	})
+	ctx, stop := context.WithTimeout(context.Background(), time.Second)
+	defer stop()
+	notice, err := c.NextCancellation(ctx)
+	if err != nil || notice.AttemptID != workerTestAttempt || notice.Epoch != 1 {
+		t.Fatalf("notice: %v", err)
+	}
+	cancelled, cancel := context.WithCancel(ctx)
+	cancel()
+	if _, err := c.NextCancellation(cancelled); !errors.Is(err, context.Canceled) {
+		t.Fatal("cancelled read did not end")
+	}
+	if c.Err() != nil {
+		t.Fatal("cancelled wait closed connection")
+	}
+	now := time.Now()
+	lease := WorkerLease{Active: true, State: "RUNNING", ServerTime: now, LeaseUntil: now.Add(time.Second), CancelRequestedAt: &now}
+	if err := lease.confirm(now); err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := lease.ExecutionDeadline(); ok {
+		t.Fatal("cancel intent still granted execution")
+	}
+}