// submit basically invokes the processing function (instrumented) and tries to buffer to graphite
func (s *StatsDaemon) submit(c *counters.Counters, g *gauges.Gauges, t *timers.Timers, deadline time.Time) error {
var buffer bytes.Buffer
now := time.Now().Unix()
// TODO: in future, buffer up data (with a TTL/max size) and submit later
client, err := net.Dial("tcp", s.graphite_addr)
if err != nil {
// todo: remove these
c.Process(&buffer, now, s.flushInterval)
g.Process(&buffer, now, s.flushInterval)
t.Process(&buffer, now, s.flushInterval)
errmsg := fmt.Sprintf("dialing %s failed - %s", s.graphite_addr, err.Error())
return errors.New(errmsg)
}
defer client.Close()
err = client.SetDeadline(deadline)
if err != nil {
errmsg := fmt.Sprintf("could not set deadline - %s", err.Error())
return errors.New(errmsg)
}
s.instrument(c, &buffer, now, "counter")
s.instrument(g, &buffer, now, "gauge")
s.instrument(t, &buffer, now, "timer")
if s.debug {
for _, line := range bytes.Split(buffer.Bytes(), []byte("\n")) {
if len(line) == 0 {
continue
}
log.Printf("DEBUG: WRITING %s", line)
}
}
time_start := time.Now()
_, err = client.Write(buffer.Bytes())
if err != nil {
errmsg := fmt.Sprintf("failed to write stats - %s", err)
return errors.New(errmsg)
}
time_end := time.Now()
duration_ms := float64(time_end.Sub(time_start).Nanoseconds()) / float64(1000000)
if s.debug {
log.Println("submit() successfully finished")
}
buffer.Reset()
fmt.Fprintf(&buffer, "%starget_type_is_gauge.type_is_send.unit_is_ms %f %d\n", s.prefix, duration_ms, now)
_, err = client.Write(buffer.Bytes())
if err != nil {
errmsg := fmt.Sprintf("failed to write target_type_is_gauge.type_is_send.unit_is_ms - %s", err)
return errors.New(errmsg)
}
return nil
}
// metricsMonitor basically guards the metrics datastructures.
// it typically receives metrics on the Metrics channel but also responds to
// external signals and every flushInterval, computes and flushes the data
func (s *StatsDaemon) metricsMonitor() {
period := time.Duration(s.flushInterval) * time.Second
tick := ticker.GetAlignedTicker(period)
var c *counters.Counters
var g *gauges.Gauges
var t *timers.Timers
initializeCounters := func() {
c = counters.New(s.prefix_rates)
g = gauges.New(s.prefix_gauges)
t = timers.New(s.prefix_timers, s.pct)
for _, name := range []string{"timer", "gauge", "counter"} {
c.Add(&common.Metric{
Bucket: fmt.Sprintf("%sdirection_is_in.statsd_type_is_%s.target_type_is_count.unit_is_Metric", s.prefix, name),
Sampling: 1,
})
}
}
initializeCounters()
for {
select {
case sig := <-s.signalchan:
switch sig {
case syscall.SIGTERM, syscall.SIGINT:
fmt.Printf("!! Caught signal %s... shutting down\n", sig)
if err := s.submit(c, g, t, time.Now().Add(period)); err != nil {
log.Printf("ERROR: %s", err)
}
return
default:
fmt.Printf("unknown signal %s, ignoring\n", sig)
}
case <-tick.C:
go func(c *counters.Counters, g *gauges.Gauges, t *timers.Timers) {
if err := s.submit(c, g, t, time.Now().Add(period)); err != nil {
log.Printf("ERROR: %s", err)
}
s.events.Broadcast <- "flush"
}(c, g, t)
initializeCounters()
tick = ticker.GetAlignedTicker(period)
case m := <-s.Metrics:
var name string
if m.Modifier == "ms" {
t.Add(m)
name = "timer"
} else if m.Modifier == "g" {
if m.IsDelta {
log.Fatal("delta gauge:", m)
}
g.Add(m)
name = "gauge"
} else if m.Modifier == "c" {
c.Add(m)
name = "counter"
} else {
name = "unknown"
}
c.Add(&common.Metric{
Bucket: fmt.Sprintf("%sdirection_is_in.statsd_type_is_%s.target_type_is_count.unit_is_Metric", s.prefix, name),
Value: 1,
Sampling: 1,
})
}
}
}