Simple Saga

simple_saga.go

package main

import (
    "errors"
    "fmt"
)

type Step func() error
type RollbackStep func() error

type Saga struct {
    steps       []Step
    rollbacks   []RollbackStep
}

func (s *Saga) AddStep(step Step, rollback RollbackStep) {
    s.steps = append(s.steps, step)
    s.rollbacks = append(s.rollbacks, rollback)
}

func (s *Saga) Execute() error {
    for i, step := range s.steps {
        if err := step(); err != nil {
            for j := i; j >= 0; j-- {
                if rbErr := s.rollbacks[j](); rbErr != nil {
                    fmt.Printf("rollback step %d failed: %v\n", j, rbErr)
                }
            }
            return err
        }
    }
    return nil
}

func main() {
    saga := &Saga{}

    // 添加步骤和对应的回滚操作
    saga.AddStep(
        func() error {
            fmt.Println("Step 1")
            return nil
        },
        func() error {
            fmt.Println("Rollback Step 1")
            return nil
        },
    )

    saga.AddStep(
        func() error {
            fmt.Println("Step 2")
            return nil
        },
        func() error {
            fmt.Println("Rollback Step 2")
            return nil
        },
    )

    saga.AddStep(
        func() error {
            fmt.Println("Step 3")
            return errors.New("error in Step 3")
        },
        func() error {
            fmt.Println("Rollback Step 3")
            return nil
        },
    )

    // 执行Saga
    if err := saga.Execute(); err != nil {
        fmt.Printf("Saga failed: %v\n", err)
    }
}