feat: media duplicate purge, part 2 of 3: the automatic purge scheduler (Go only)

internal/infrastructure/scheduler/runner.go

@@ -0,0 +1,75 @@
+package scheduler
+
+import (
+	"RenewCMS/internal/domain/purge"
+	"context"
+	"errors"
+	"log"
+	"time"
+)
+
+const (
+	TickInterval = time.Hour
+	StartupDelay = time.Minute
+)
+
+type Job interface {
+	Tick(now time.Time) (purge.RunResult, bool, error)
+}
+
+type Runner struct {
+	job     Job
+	now     func() time.Time
+	ticks   <-chan time.Time
+	startup <-chan time.Time
+	logger  *log.Logger
+	release func()
+}
+
+func NewRunner(job Job, now func() time.Time, ticks <-chan time.Time, startup <-chan time.Time, logger *log.Logger) *Runner {
+	return &Runner{job: job, now: now, ticks: ticks, startup: startup, logger: logger, release: func() {}}
+}
+
+func NewSystemRunner(job Job, logger *log.Logger) *Runner {
+	ticker := time.NewTicker(TickInterval)
+	startup := time.NewTimer(StartupDelay)
+	runner := NewRunner(job, time.Now, ticker.C, startup.C, logger)
+	runner.release = func() {
+		ticker.Stop()
+		startup.Stop()
+	}
+	return runner
+}
+
+func (r *Runner) Run(ctx context.Context) {
+	defer r.release()
+	startup := r.startup
+	for ctx.Err() == nil {
+		select {
+		case <-ctx.Done():
+			return
+		case <-startup:
+			startup = nil
+			r.tick(ctx)
+		case <-r.ticks:
+			r.tick(ctx)
+		}
+	}
+}
+
+func (r *Runner) tick(ctx context.Context) {
+	if ctx.Err() != nil {
+		return
+	}
+	result, ran, err := r.job.Tick(r.now())
+	if errors.Is(err, purge.ErrPurgeBusy) {
+		return
+	}
+	if err != nil {
+		r.logger.Printf("scheduler: automatic purge failed: %v", err)
+		return
+	}
+	if ran {
+		r.logger.Printf("scheduler: automatic purge completed: groups_purged=%d merged=%d articles_updated=%d failed_groups=%d", result.GroupsPurged, result.Merged, result.ArticlesUpdated, result.FailedGroups)
+	}
+}