init

manager.go

@@ -0,0 +1,226 @@
+package reconnect
+
+import (
+	"context"
+	"log"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// HealthChecker 健康检查接口
+type HealthChecker interface {
+	// HealthCheck 执行健康检查，返回 nil 表示健康
+	HealthCheck(ctx context.Context) error
+}
+
+// Connector 连接器接口
+type Connector interface {
+	// Connect 建立连接
+	Connect(ctx context.Context) error
+	// Close 关闭连接
+	Close() error
+}
+
+// ConnectionManager 连接管理器
+type ConnectionManager struct {
+	config    Config
+	strategy  Strategy
+	connector Connector
+	checker   HealthChecker
+
+	state     atomic.Int32
+	attempts  atomic.Int32
+	mu        sync.RWMutex
+	ctx       context.Context
+	cancel    context.CancelFunc
+	wg        sync.WaitGroup
+	closeOnce sync.Once
+}
+
+// NewConnectionManager 创建连接管理器
+func NewConnectionManager(connector Connector, checker HealthChecker, cfg Config) *ConnectionManager {
+	cfg.Validate()
+	ctx, cancel := context.WithCancel(context.Background())
+
+	cm := &ConnectionManager{
+		config:    cfg,
+		strategy:  NewStrategy(cfg),
+		connector: connector,
+		checker:   checker,
+		ctx:       ctx,
+		cancel:    cancel,
+	}
+
+	cm.state.Store(int32(StateDisconnected))
+	return cm
+}
+
+// State 获取当前连接状态
+func (cm *ConnectionManager) State() ConnectionState {
+	return ConnectionState(cm.state.Load())
+}
+
+// setState 设置连接状态
+func (cm *ConnectionManager) setState(newState ConnectionState) {
+	oldState := ConnectionState(cm.state.Swap(int32(newState)))
+	if oldState != newState && cm.config.OnStateChange != nil {
+		cm.config.OnStateChange(oldState, newState)
+	}
+}
+
+// Connect 建立连接并启动健康检查
+func (cm *ConnectionManager) Connect(ctx context.Context) error {
+	cm.setState(StateConnecting)
+
+	if err := cm.connector.Connect(ctx); err != nil {
+		cm.setState(StateDisconnected)
+		if cm.config.OnError != nil {
+			cm.config.OnError(err)
+		}
+		return err
+	}
+
+	cm.setState(StateConnected)
+	cm.strategy.Reset()
+	cm.attempts.Store(0)
+
+	// 启动健康检查
+	if cm.checker != nil && cm.config.HealthCheckInterval > 0 {
+		cm.wg.Add(1)
+		go cm.healthCheckLoop()
+	}
+
+	return nil
+}
+
+// ConnectWithRetry 带重试的连接
+func (cm *ConnectionManager) ConnectWithRetry(ctx context.Context) error {
+	cm.setState(StateConnecting)
+
+	for {
+		select {
+		case <-ctx.Done():
+			cm.setState(StateDisconnected)
+			return ctx.Err()
+		case <-cm.ctx.Done():
+			cm.setState(StateDisconnected)
+			return cm.ctx.Err()
+		default:
+		}
+
+		attempt := int(cm.attempts.Add(1))
+
+		if err := cm.connector.Connect(ctx); err != nil {
+			if cm.config.OnError != nil {
+				cm.config.OnError(err)
+			}
+
+			// 检查是否超过最大重试次数
+			if cm.config.MaxRetries >= 0 && attempt >= cm.config.MaxRetries {
+				cm.setState(StateDisconnected)
+				return err
+			}
+
+			delay := cm.strategy.NextDelay(attempt)
+			log.Printf("[reconnect] 连接失败 (尝试 %d): %v, %v 后重试...", attempt, err, delay)
+
+			select {
+			case <-ctx.Done():
+				cm.setState(StateDisconnected)
+				return ctx.Err()
+			case <-cm.ctx.Done():
+				cm.setState(StateDisconnected)
+				return cm.ctx.Err()
+			case <-time.After(delay):
+				continue
+			}
+		}
+
+		// 连接成功
+		cm.setState(StateConnected)
+		cm.strategy.Reset()
+		cm.attempts.Store(0)
+
+		if cm.config.OnReconnect != nil && attempt > 1 {
+			cm.config.OnReconnect(attempt)
+		}
+
+		// 启动健康检查
+		if cm.checker != nil && cm.config.HealthCheckInterval > 0 {
+			cm.wg.Add(1)
+			go cm.healthCheckLoop()
+		}
+
+		log.Printf("[reconnect] 连接成功")
+		return nil
+	}
+}
+
+// healthCheckLoop 健康检查循环
+func (cm *ConnectionManager) healthCheckLoop() {
+	defer cm.wg.Done()
+
+	ticker := time.NewTicker(cm.config.HealthCheckInterval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-cm.ctx.Done():
+			return
+		case <-ticker.C:
+			if cm.State() != StateConnected {
+				continue
+			}
+
+			ctx, cancel := context.WithTimeout(cm.ctx, cm.config.HealthCheckTimeout)
+			err := cm.checker.HealthCheck(ctx)
+			cancel()
+
+			if err != nil {
+				log.Printf("[reconnect] 健康检查失败: %v, 开始重连...", err)
+				if cm.config.OnError != nil {
+					cm.config.OnError(err)
+				}
+				cm.reconnect()
+			}
+		}
+	}
+}
+
+// reconnect 执行重连
+func (cm *ConnectionManager) reconnect() {
+	if cm.State() == StateReconnecting {
+		return // 已经在重连中
+	}
+
+	cm.setState(StateReconnecting)
+
+	// 关闭旧连接
+	_ = cm.connector.Close()
+
+	// 重新连接
+	go func() {
+		if err := cm.ConnectWithRetry(cm.ctx); err != nil {
+			log.Printf("[reconnect] 重连失败: %v", err)
+		}
+	}()
+}
+
+// Close 关闭连接管理器
+func (cm *ConnectionManager) Close() error {
+	var err error
+	cm.closeOnce.Do(func() {
+		cm.cancel()
+		cm.wg.Wait()
+		err = cm.connector.Close()
+		cm.setState(StateDisconnected)
+	})
+	return err
+}
+
+// TriggerReconnect 手动触发重连
+func (cm *ConnectionManager) TriggerReconnect() {
+	cm.reconnect()
+}
+