Go语言分布式事务：TCC模式实战
1. TCC模式概述
TCC（Try-Confirm-Cancel）是一种常用的分布式事务解决方案，将业务逻辑拆分为三个阶段：
- Try：预留资源，锁定事务
- Confirm：确认执行，使用预留资源
- Cancel：取消执行，释放预留资源
2. TCC框架实现
type TCCContext struct { TryTasks []TryTask ConfirmTasks []ConfirmTask CancelTasks []CancelTask } type TryTask func(ctx context.Context) error type ConfirmTask func(ctx context.Context) error type CancelTask func(ctx context.Context) error type TCCService struct { transactions map[string]*TCCContext mu sync.RWMutex } func (s *TCCService) Register(id string, try TryTask, confirm ConfirmTask, cancel CancelTask) { s.mu.Lock() defer s.mu.Unlock() s.transactions[id] = &TCCContext{ TryTasks: []TryTask{try}, ConfirmTasks: []ConfirmTask{confirm}, CancelTasks: []CancelTask{cancel}, } } func (s *TCCService) Execute(ctx context.Context, id string) error { s.mu.RLock() tx, ok := s.transactions[id] s.mu.RUnlock() if !ok { return errors.New("transaction not found") } for _, try := range tx.TryTasks { if err := try(ctx); err != nil { s.rollback(ctx, tx) return err } } for _, confirm := range tx.ConfirmTasks { if err := confirm(ctx); err != nil { s.rollback(ctx, tx) return err } } return nil } func (s *TCCService) rollback(ctx context.Context, tx *TCCContext) { for _, cancel := range tx.CancelTasks { cancel(ctx) } }3. 实战示例
func Transfer(from, to string, amount int64) error { tccService := NewTCCService() tccService.Register("transfer", func(ctx context.Context) error { return FreezeAccount(ctx, from, amount) }, func(ctx context.Context) error { return ConfirmTransfer(ctx, from, to, amount) }, func(ctx context.Context) error { return UnfreezeAccount(ctx, from, amount) }, ) return tccService.Execute(context.Background(), "transfer") }4. 总结
TCC模式通过将分布式事务拆分为三个阶段，结合业务层面的补偿逻辑，实现了柔性事务的最终一致性。
