chore: import upstream snapshot with attribution

flow/schedule.go

@@ -0,0 +1,60 @@
+package flow
+
+import (
+	"context"
+	"time"
+
+	"go-micro.dev/v6/ai"
+)
+
+// Schedule binds a flow to a recurring work item without introducing a
+// scheduler service. It is a small harness contract: callers own the clock,
+// Go Micro owns turning each tick into the same inspectable flow run used for
+// broker events and direct Execute calls.
+type Schedule struct {
+	flow *Flow
+	data string
+}
+
+// Scheduled returns a deterministic scheduled-run harness for this flow.
+// Tests and event loops can call Tick directly; production processes can wire
+// the same contract to time.Ticker through RunEvery. Each tick calls Execute, so
+// checkpointed run history, parent/run metadata, cancellation, and inspection
+// stay on the normal flow surfaces.
+func Scheduled(f *Flow, data string) Schedule {
+	return Schedule{flow: f, data: data}
+}
+
+// Tick starts one scheduled run immediately and returns when that run finishes.
+func (s Schedule) Tick(ctx context.Context) error {
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	info, _ := ai.RunInfoFrom(ctx)
+	info.Dispatch = "schedule"
+	if info.Trigger == "" {
+		info.Trigger = s.flow.opts.TriggerTopic
+	}
+	if info.Trigger == "" {
+		info.Trigger = "schedule"
+	}
+	return s.flow.Execute(ai.WithRunInfo(ctx, info), s.data)
+}
+
+// RunEvery drives scheduled runs from a ticker until ctx is canceled. It does
+// not persist schedule definitions or host a scheduler; it only adapts a caller
+// owned cadence to Tick.
+func (s Schedule) RunEvery(ctx context.Context, interval time.Duration) error {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		case <-ticker.C:
+			if err := s.Tick(ctx); err != nil {
+				return err
+			}
+		}
+	}
+}