package utils import ( "errors" "github.com/spf13/viper" "net" "sync" "time" ) // 获取新的程序生成的编号 func NextId() Long { id, e := SingletonSnowflakeKeyGen().NextId() if nil != e { println("get next id failed", e) return 0 } return Long(id) } /*------------------------------------------------------Singleton----------------------------------------------------*/ var snowflakeKeyGen *Snowflake var once sync.Once func SingletonSnowflakeKeyGen() *Snowflake { once.Do(func() { snowflakeKeyGen = NewSnowflake(SnowflakeSettings{}) }) return snowflakeKeyGen } /*----------------------------------------------------SnowflakeKeyGen------------------------------------------------*/ const ( SnowflakeTimeUnit = 1e7 // 时间单位,一纳秒的多少倍,1e6 = 一毫秒,1e7 = 百分之一秒,1e8 = 十分之一秒 BitLenSequence = 8 // 序列号的个数最多256个(0-255),即每单位时间并发数,如时间单位是1e7,则单实例qps = 25600 BitLenDataCenterId = 3 // 数据中心个数最多8个(0-7),即同一个环境(生产、预发布、测试等)的数据中心(假设一个机房相同数据域的应用服务器集群只有一个,则数据中心数等于机房数)最多有8个 BitLenMachineId = 16 // 同一个数据中心下最多65536个应用实例(0-65535),默认是根据实例ip后两段算实例id(k8s环境动态创建Pod,也建议用此方式),所以需要预留255 * 255这么多 BitLenTime = 36 // 时间戳之差最大 = 2的36次方 * 时间单位 / 1e9 秒,目前的设计最多可以用21.79年就需要更新开始时间(随之还需要归档旧数据和更新次新数据id) // 总共63位,不超过bit64 ) type SnowflakeSettings struct { StartTime time.Time DataCenterId func() (uint16, error) MachineId func() (uint16, error) CheckMachineId func(uint16) bool } type Snowflake struct { mutex *sync.Mutex startTime int64 elapsedTime int64 sequence uint16 dataCenterId uint16 machineId uint16 } func NewSnowflake(st SnowflakeSettings) *Snowflake { sf := new(Snowflake) sf.mutex = new(sync.Mutex) sf.sequence = uint16(1< 0 { // 没有配置会尝试从配置文件读取数据中心id sf.dataCenterId = uint16(id) } else { // 如果配置文件也没有,默认数据中心id为0 sf.dataCenterId = uint16(0) } } else { sf.dataCenterId, err = st.DataCenterId() if nil != err { sf.dataCenterId = uint16(0) } } if st.CheckMachineId != nil && !st.CheckMachineId(sf.machineId) { return nil } return sf } func (sf *Snowflake) NextId() (uint64, error) { const maskSequence = uint16(1<= current sf.sequence = (sf.sequence + 1) & maskSequence if sf.sequence == 0 { sf.elapsedTime++ overtime := sf.elapsedTime - current time.Sleep(sleepTime(overtime)) } } return sf.toId() } func toSnowflakeTime(t time.Time) int64 { return t.UTC().UnixNano() / SnowflakeTimeUnit } func currentElapsedTime(startTime int64) int64 { return toSnowflakeTime(time.Now()) - startTime } func sleepTime(overtime int64) time.Duration { return time.Duration(overtime)*10*time.Millisecond - time.Duration(time.Now().UTC().UnixNano()%SnowflakeTimeUnit)*time.Nanosecond } func (sf *Snowflake) toId() (uint64, error) { if sf.elapsedTime >= 1<= 16 && ip[1] < 32) || ip[0] == 192 && ip[1] == 168) } func GetPrivateIPv4Id() (uint16, error) { ip, err := privateIPv4() if err != nil { return 0, err } return uint16(ip[2])<<8 + uint16(ip[3]), nil } func Decompose(id uint64) map[string]uint64 { const maskDataCenterId = uint64((1<> BitLenMachineId machineId := id & maskMachineId return map[string]uint64{ "id": id, "dataCenterId": dataCenterId, "machineId": machineId, } }