package main import ( "encoding/json" "io/ioutil" "log" "os" "sync" "time" ) type Node struct { Firstseen time.Time `json:"firstseen"` Lastseen time.Time `json:"lastseen"` Statistics interface{} `json:"statistics"` Nodeinfo interface{} `json:"nodeinfo"` Neighbours interface{} `json:"neighbours"` } type Nodes struct { Version int `json:"version"` Timestamp time.Time `json:"timestamp"` List map[string]*Node `json:"nodes"` // the current nodemap sync.Mutex } func NewNodes() *Nodes { nodes := &Nodes{ Version: 1, List: make(map[string]*Node), } go nodes.saver() return nodes } func (nodes *Nodes) get(nodeId string) *Node { now := time.Now() nodes.Lock() node, _ := nodes.List[nodeId] if node == nil { node = &Node{ Firstseen: now, } nodes.List[nodeId] = node } nodes.Unlock() node.Lastseen = now return node } func (nodes *Nodes) saver() { c := time.Tick(saveInterval) for range c { nodes.save() } } func (nodes *Nodes) save() { nodes.Timestamp = time.Now() nodes.Lock() data, err := json.Marshal(nodes) nodes.Unlock() if err !=nil{ log.Panic(err) } log.Println("saving", len(nodes.List), "nodes") tmpFile := outputFile + ".tmp" err = ioutil.WriteFile(tmpFile, data, 0644) if err !=nil{ log.Panic(err) } err = os.Rename(tmpFile, outputFile) if err !=nil{ log.Panic(err) } }