feat(deploy): 在线更新 - 新增后台检查、强制备份迁移与失败自动回退

backend/internal/service/worker_runtime.go

@@ -0,0 +1,95 @@
+package service
+
+import (
+	"context"
+	"sync"
+	"sync/atomic"
+)
+
+type workerRuntime struct {
+	mu          sync.Mutex
+	ctx         context.Context
+	cancel      context.CancelFunc
+	wg          sync.WaitGroup
+	started     bool
+	draining    atomic.Bool
+	activeTasks atomic.Int64
+}
+
+func (r *workerRuntime) start() (context.Context, bool) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.started {
+		return r.ctx, false
+	}
+	r.ctx, r.cancel = context.WithCancel(context.Background())
+	r.started = true
+	r.draining.Store(false)
+	return r.ctx, true
+}
+
+func (r *workerRuntime) goLoop(fn func(context.Context)) bool {
+	r.mu.Lock()
+	if !r.started || r.draining.Load() {
+		r.mu.Unlock()
+		return false
+	}
+	ctx := r.ctx
+	r.wg.Add(1)
+	r.mu.Unlock()
+	go func() {
+		defer r.wg.Done()
+		fn(ctx)
+	}()
+	return true
+}
+
+func (r *workerRuntime) goTask(fn func()) bool {
+	r.mu.Lock()
+	if !r.started || r.draining.Load() {
+		r.mu.Unlock()
+		return false
+	}
+	r.wg.Add(1)
+	r.activeTasks.Add(1)
+	r.mu.Unlock()
+	go func() {
+		defer r.wg.Done()
+		defer r.activeTasks.Add(-1)
+		fn()
+	}()
+	return true
+}
+
+func (r *workerRuntime) beginDrain() {
+	r.mu.Lock()
+	r.draining.Store(true)
+	if r.cancel != nil {
+		r.cancel()
+	}
+	r.mu.Unlock()
+}
+
+func (r *workerRuntime) stop(ctx context.Context) error {
+	r.beginDrain()
+	done := make(chan struct{})
+	go func() {
+		r.wg.Wait()
+		close(done)
+	}()
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-done:
+		r.mu.Lock()
+		r.started = false
+		r.ctx = nil
+		r.cancel = nil
+		r.mu.Unlock()
+		return nil
+	}
+}
+
+func (r *workerRuntime) isDraining() bool { return r.draining.Load() }
+
+func (r *workerRuntime) activeTaskCount() int64 { return r.activeTasks.Load() }