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本文主要研究一下dubbo-go-proxy的recoveryFilter

recoveryFilter

dubbo-go-proxy/pkg/filter/recovery/recovery.go

func Init() {
    extension.SetFilterFunc(constant.RecoveryFilter, recoveryFilterFunc())
}

func recoveryFilterFunc() context.FilterFunc {
    return New().Do()
}

// recoveryFilter is a filter for recover.
type recoveryFilter struct {
}

// New create timeout filter.
func New() filter.Filter {
    return &recoveryFilter{}
}

recoveryFilter往extension注册名为dgp.filters.recovery的recoveryFilterFunc；该func执行的是recoveryFilter的Do方法

Do

dubbo-go-proxy/pkg/filter/recovery/recovery.go

// Recovery execute recoveryFilter filter logic, if recover happen, print log or do other things.
func (f recoveryFilter) Do() context.FilterFunc {
    return func(c context.Context) {
        defer func() {
            if err := recover(); err != nil {
                logger.Warnf("[dubboproxy go] error:%+v", err)

                c.WriteErr(err)
            }
        }()
        c.Next()
    }
}

Do方法先注册一个defer func进行recover，然后再执行c.Next()

小结

dubbo-go-proxy的recoveryFilter注册一个defer func进行recover，然后再执行c.Next()。

doc

• dubbo-go-proxy