package sequence import ( "fmt" "hash/fnv" "github.com/bwmarrin/snowflake" "github.com/seaweedfs/seaweedfs/weed/glog" ) // a simple snowflake Sequencer type SnowflakeSequencer struct { node *snowflake.Node } func NewSnowflakeSequencer(nodeid string, snowflakeId int) (*SnowflakeSequencer, error) { nodeid_hash := hash(nodeid) & 0x3ff if snowflakeId != 0 { nodeid_hash = uint32(snowflakeId) } glog.V(0).Infof("use snowflake seq id generator, nodeid:%s hex_of_nodeid: %x", nodeid, nodeid_hash) node, err := snowflake.NewNode(int64(nodeid_hash)) if err != nil { fmt.Println(err) return nil, err } sequencer := &SnowflakeSequencer{node: node} return sequencer, nil } func hash(s string) uint32 { h := fnv.New32a() h.Write([]byte(s)) return h.Sum32() } func (m *SnowflakeSequencer) NextFileId(count uint64) uint64 { return uint64(m.node.Generate().Int64()) } // ignore setmax as we are snowflake func (m *SnowflakeSequencer) SetMax(seenValue uint64) { } // return a new id as no Peek is stored func (m *SnowflakeSequencer) Peek() uint64 { return uint64(m.node.Generate().Int64()) }