yanic/collector.go
Julian Kornberger 7b61f9f5ab First code
2015-12-29 14:12:21 +01:00

119 lines
2.1 KiB
Go

package main
import (
"encoding/json"
"log"
"net"
"time"
)
const (
maxDatagramSize = 8192
)
type Node struct {
Firstseen time.Time `json:"firstseen"`
Lastseen time.Time `json:"lastseen"`
Statistics interface{} `json:"statistics"`
Nodeinfo interface{} `json:"nodeinfo"`
}
type Collector struct {
connection *net.UDPConn // UDP socket
queue chan string // received responses
nodes map[string]*Node // the current nodemap
}
func NewCollector() *Collector {
// Parse address
addr, err := net.ResolveUDPAddr("udp", "[::]:1001")
if err != nil {
log.Panic(err)
}
// Open socket
conn, err := net.ListenUDP("udp", addr)
if err != nil {
log.Panic(err)
}
conn.SetReadBuffer(maxDatagramSize)
collector := &Collector{
connection: conn,
queue: make(chan string, 100),
nodes: make(map[string]*Node),
}
go collector.receiver()
go collector.parser()
return collector
}
func (coll *Collector) Close() {
coll.connection.Close()
close(coll.queue)
}
func (coll *Collector) send(address string) {
addr, err := net.ResolveUDPAddr("udp", address)
if err != nil {
log.Panic(err)
}
coll.connection.WriteToUDP([]byte("nodeinfo"), addr)
}
func (coll *Collector) print() {
b, err := json.Marshal(coll.nodes)
if err != nil {
log.Panic(err)
}
log.Println(string(b))
}
func (coll *Collector) parser() {
for str := range coll.queue {
coll.parseSingle(str)
coll.print()
}
}
// Parst die Rückgabe
func (coll *Collector) parseSingle(str string) {
var result map[string]interface{}
json.Unmarshal([]byte(str), &result)
nodeId, _ := result["node_id"].(string)
if nodeId == "" {
log.Println("unable to parse node_id")
return
}
now := time.Now()
node, _ := coll.nodes[nodeId]
if node == nil {
node = &Node{
Firstseen: now,
}
coll.nodes[nodeId] = node
}
node.Lastseen = now
node.Nodeinfo = result
}
func (coll *Collector) receiver() {
b := make([]byte, maxDatagramSize)
for {
n, _, err := coll.connection.ReadFromUDP(b)
if err != nil {
log.Println("ReadFromUDP failed:", err)
} else {
coll.queue <- string(b[:n])
}
}
}