func Example_customHandler() {
var data = []byte("measure.a=1ms measure.b=10 measure.c=100MB measure.d=1s garbage")
mm := make(Measurements, 0)
if err := logfmt.Unmarshal(data, &mm); err != nil {
log.Fatalf("err=%q", err)
}
for _, m := range mm {
fmt.Printf("%v\n", *m)
}
// Output:
// {a 1 ms}
// {b 10 }
// {c 100 MB}
// {d 1 s}
}
// "Parse tree" from hell
func (s *server) serveDrain(w http.ResponseWriter, r *http.Request) {
s.Add(1)
defer s.Done()
w.Header().Set("Content-Length", "0")
if r.Method != "POST" {
w.WriteHeader(http.StatusMethodNotAllowed)
wrongMethodErrorCounter.Inc(1)
return
}
id := r.Header.Get("Logplex-Drain-Token")
batchCounter.Inc(1)
parseStart := time.Now()
lp := lpx.NewReader(bufio.NewReader(r.Body))
linesCounterInc := 0
for lp.Next() {
linesCounterInc++
header := lp.Header()
// If the syslog Name Header field contains what looks like a log token,
// let's assume it's an override of the id and we're getting the data from the magic
// channel
if bytes.HasPrefix(header.Name, TokenPrefix) {
id = string(header.Name)
}
// If we still don't have an id, throw an error and try the next line
if id == "" {
tokenMissingCounter.Inc(1)
continue
}
destination := s.hashRing.Get(id)
msg := lp.Bytes()
switch {
case bytes.Equal(header.Name, Heroku), bytes.HasPrefix(header.Name, TokenPrefix):
timeStr := string(lp.Header().Time)
t, e := time.Parse("2006-01-02T15:04:05.000000+00:00", timeStr)
if e != nil {
t, e = time.Parse("2006-01-02T15:04:05+00:00", timeStr)
if e != nil {
timeParsingErrorCounter.Inc(1)
log.Printf("Error Parsing Time(%s): %q\n", string(lp.Header().Time), e)
continue
}
}
timestamp := t.UnixNano() / int64(time.Microsecond)
pid := string(header.Procid)
switch pid {
case "router":
switch {
// router logs with a H error code in them
case bytes.Contains(msg, keyCodeH):
routerErrorLinesCounter.Inc(1)
re := routerError{}
err := logfmt.Unmarshal(msg, &re)
if err != nil {
handleLogFmtParsingError(msg, err)
continue
}
// Track the breakout of different error types.
metrics.GetOrRegisterCounter("lumbermill.lines.router.errors."+re.Code, metrics.DefaultRegistry).Inc(1)
if debugToken != "" && id == debugToken {
log.Printf("debug=error.%s %s", re.Code, msg)
}
destination.PostPoint(point{id, routerEvent, []interface{}{timestamp, re.Code}})
// If the app is blank (not pushed) we don't care
// do nothing atm, increment a counter
case bytes.Contains(msg, keyCodeBlank), bytes.Contains(msg, keyDescBlank):
routerBlankLinesCounter.Inc(1)
// likely a standard router log
default:
routerLinesCounter.Inc(1)
rm := routerMsg{}
err := logfmt.Unmarshal(msg, &rm)
if err != nil {
handleLogFmtParsingError(msg, err)
continue
}
destination.PostPoint(point{id, routerRequest, []interface{}{timestamp, rm.Status, rm.Service}})
}
// Non router logs, so either dynos, runtime, etc
default:
switch {
// Dyno error messages
case bytes.HasPrefix(msg, dynoErrorSentinel):
dynoErrorLinesCounter.Inc(1)
de, err := parseBytesToDynoError(msg)
if err != nil {
handleLogFmtParsingError(msg, err)
continue
}
what := string(lp.Header().Procid)
destination.PostPoint(
point{id, dynoEvents, []interface{}{timestamp, what, "R", de.Code, string(msg), dynoType(what)}},
)
// Dyno log-runtime-metrics memory messages
case bytes.Contains(msg, dynoMemMsgSentinel):
s.maybeUpdateRecentTokens(destination.Name, id)
dynoMemLinesCounter.Inc(1)
dm := dynoMemMsg{}
err := logfmt.Unmarshal(msg, &dm)
if err != nil {
handleLogFmtParsingError(msg, err)
continue
}
if dm.Source != "" {
destination.PostPoint(
point{
id,
dynoMem,
[]interface{}{
timestamp,
dm.Source,
dm.MemoryCache,
dm.MemoryPgpgin,
dm.MemoryPgpgout,
dm.MemoryRSS,
dm.MemorySwap,
dm.MemoryTotal,
dynoType(dm.Source),
},
},
)
}
// Dyno log-runtime-metrics load messages
case bytes.Contains(msg, dynoLoadMsgSentinel):
s.maybeUpdateRecentTokens(destination.Name, id)
dynoLoadLinesCounter.Inc(1)
dm := dynoLoadMsg{}
err := logfmt.Unmarshal(msg, &dm)
if err != nil {
handleLogFmtParsingError(msg, err)
continue
}
if dm.Source != "" {
destination.PostPoint(
point{
id,
dynoLoad,
[]interface{}{timestamp, dm.Source, dm.LoadAvg1Min, dm.LoadAvg5Min, dm.LoadAvg15Min, dynoType(dm.Source)},
},
)
}
// unknown
default:
unknownHerokuLinesCounter.Inc(1)
if debug {
log.Printf("Unknown Heroku Line - Header: PRI: %s, Time: %s, Hostname: %s, Name: %s, ProcId: %s, MsgId: %s - Body: %s",
header.PrivalVersion,
header.Time,
header.Hostname,
header.Name,
header.Procid,
header.Msgid,
string(msg),
)
}
}
}
// non heroku lines
default:
unknownUserLinesCounter.Inc(1)
if debug {
log.Printf("Unknown User Line - Header: PRI: %s, Time: %s, Hostname: %s, Name: %s, ProcId: %s, MsgId: %s - Body: %s",
header.PrivalVersion,
header.Time,
header.Hostname,
header.Name,
header.Procid,
header.Msgid,
string(msg),
)
}
}
}
linesCounter.Inc(int64(linesCounterInc))
batchSizeHistogram.Update(int64(linesCounterInc))
parseTimer.UpdateSince(parseStart)
w.WriteHeader(http.StatusNoContent)
}