package server import ( "crypto/md5" "fmt" "io" "time" ) // This thing contains a channel that when initialized (see NewIdGenerator) // will return a bunch of (as best as I can tell) unique md5 hashes. // // we use this for naming players, games, etc. // // It will consume a single goroutine type IdGenerator struct { id chan int64 } func NewIdGenerator() *IdGenerator { return &IdGenerator{ id: make(chan int64), } } // Run is called (typically in a gorotine) to allow for queries to be made // against IdGenerator.id throgh the Hash method. func (idg *IdGenerator) Run() { var i int64 for i = 0; ; i++ { idg.id <- i } } // Hash is the method used by a properly instantiated IdGenerator that gives // fairly unique strings. They are currently truncated md5 hashes of the time // plus a unique counter func (id *IdGenerator) Hash() string { h := md5.New() ns := time.Now().UnixNano() + <-id.id io.WriteString(h, fmt.Sprintf("%d", ns)) return fmt.Sprintf("%x", h.Sum(nil))[:8] }