如何用Golang实现责任链模式_Golang 责任链模式请求处理实践

type Handler interface {
    SetNext(handler Handler)
    Handle(request string) string
}

type BaseHandler struct {
    next Handler
}

func (b *BaseHandler) SetNext(handler Handler) {
    b.next = handler
}

func (b *BaseHandler) PassToNext(request string) string {
    if b.next == nil {
        return "no more handlers"
    }
    return b.next.Handle(request)
}

type AuthHandler struct {
    BaseHandler
}

func (a *AuthHandler) Handle(request string) string {
    if isValidToken(request) {
        return "auth passed -> " + a.PassToNext(request)
    }
    return "auth failed"
}

type PermissionHandler struct {
    BaseHandler
}

func (p *PermissionHandler) Handle(request string) string {
    if hasPermission(request) {
        return "permission granted -> " + p.PassToNext(request)
    }
    return "permission denied"
}

type BusinessHandler struct {
    BaseHandler
}

func (b *BusinessHandler) Handle(request string) string {
    return "business processed"
}

func main() {
    auth := &AuthHandler{}
    perm := &PermissionHandler{}
    biz  := &BusinessHandler{}

    auth.SetNext(perm)
    perm.SetNext(biz)

    result := auth.Handle("token=admin&action=delete")
    fmt.Println(result)
}

auth passed -> permission granted -> business processed

auth passed -> permission denied