Add Reconnect package for managing automatic reconnections, including a Reconnectable interface, configuration options, and a Manager for connection monitoring and retries.

reconnect.go

@@ -0,0 +1,162 @@
+package reconnect
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+)
+
+// Reconnectable 定义可重连的接口
+type Reconnectable interface {
+	// Connect 建立连接
+	Connect(ctx context.Context) error
+	// Close 关闭连接
+	Close() error
+	// Ping 检查连接是否健康
+	Ping(ctx context.Context) error
+	// IsConnected 检查连接状态
+	IsConnected() bool
+}
+
+// Config 重连配置
+type Config struct {
+	// MaxRetries 最大重试次数，0表示无限重试
+	MaxRetries int
+	// RetryInterval 重试间隔
+	RetryInterval time.Duration
+	// Timeout 连接超时时间
+	Timeout time.Duration
+	// OnReconnect 重连成功后的回调函数
+	OnReconnect func()
+	// OnDisconnect 断开连接时的回调函数
+	OnDisconnect func(error)
+}
+
+// DefaultConfig 返回默认配置
+func DefaultConfig() *Config {
+	return &Config{
+		MaxRetries:    0, // 无限重试
+		RetryInterval: 3 * time.Second,
+		Timeout:       10 * time.Second,
+	}
+}
+
+// Manager 重连管理器
+type Manager struct {
+	client    Reconnectable
+	config    *Config
+	ctx       context.Context
+	cancel    context.CancelFunc
+	connected bool
+	errCh     chan error
+}
+
+// NewManager 创建新的重连管理器
+func NewManager(client Reconnectable, config *Config) *Manager {
+	if config == nil {
+		config = DefaultConfig()
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	return &Manager{
+		client: client,
+		config: config,
+		ctx:    ctx,
+		cancel: cancel,
+		errCh:  make(chan error, 1),
+	}
+}
+
+// Start 启动连接并开始监控
+func (m *Manager) Start(ctx context.Context) error {
+	// 初始连接
+	if err := m.connect(ctx); err != nil {
+		return fmt.Errorf("initial connection failed: %w", err)
+	}
+
+	// 启动监控 goroutine
+	go m.monitor()
+
+	return nil
+}
+
+// Stop 停止重连管理器
+func (m *Manager) Stop() error {
+	m.cancel()
+	if m.client != nil {
+		return m.client.Close()
+	}
+	return nil
+}
+
+// connect 执行连接
+func (m *Manager) connect(ctx context.Context) error {
+	connectCtx, cancel := context.WithTimeout(ctx, m.config.Timeout)
+	defer cancel()
+
+	if err := m.client.Connect(connectCtx); err != nil {
+		return err
+	}
+
+	m.connected = true
+	if m.config.OnReconnect != nil {
+		m.config.OnReconnect()
+	}
+	return nil
+}
+
+// monitor 监控连接状态并自动重连
+func (m *Manager) monitor() {
+	ticker := time.NewTicker(m.config.RetryInterval)
+	defer ticker.Stop()
+
+	retryCount := 0
+
+	for {
+		select {
+		case <-m.ctx.Done():
+			return
+		case <-ticker.C:
+			// 检查连接状态
+			if !m.client.IsConnected() {
+				m.connected = false
+				if m.config.OnDisconnect != nil {
+					m.config.OnDisconnect(errors.New("connection lost"))
+				}
+
+				// 检查是否超过最大重试次数
+				if m.config.MaxRetries > 0 && retryCount >= m.config.MaxRetries {
+					m.errCh <- fmt.Errorf("max retries (%d) exceeded", m.config.MaxRetries)
+					return
+				}
+
+				// 尝试重连
+				if err := m.connect(context.Background()); err != nil {
+					retryCount++
+					continue
+				}
+
+				// 重连成功，重置计数器
+				retryCount = 0
+			} else {
+				// 连接正常，执行健康检查
+				if err := m.client.Ping(context.Background()); err != nil {
+					m.connected = false
+					if m.config.OnDisconnect != nil {
+						m.config.OnDisconnect(err)
+					}
+				}
+			}
+		}
+	}
+}
+
+// IsConnected 返回当前连接状态
+func (m *Manager) IsConnected() bool {
+	return m.connected && m.client.IsConnected()
+}
+
+// WaitForError 等待错误（用于阻塞等待）
+func (m *Manager) WaitForError() error {
+	return <-m.errCh
+}