// processor tries to parse an http request from each packet, and if
// successful it records metrics about it in the loghisto metric system.
func processor(ms *loghisto.MetricSystem, packetsIn chan *pcap.Packet) {
for pkt := range packetsIn {
req, reqErr := http.ReadRequest(bufio.NewReader(bytes.NewReader(pkt.Payload)))
if reqErr == nil {
ms.Counter(req.Method+" "+req.URL.Path, 1)
}
}
}
// processor tries to parse an http request or response from each packet,
// and if successful it records metrics about it in the loghisto metric
// system. On successful parse of a response, it looks up a corresponding
// request so that it can record statistics about http verbs / individual
// paths being hit.
func processor(ms *loghisto.MetricSystem, packetsIn chan *pcap.Packet) {
reqTimers := map[uint32]loghisto.TimerToken{}
reqVerbTimers := map[uint32]loghisto.TimerToken{}
globalTimers := map[uint32]loghisto.TimerToken{}
reqVerb := map[uint32]string{}
for pkt := range packetsIn {
var token uint32
req, reqErr := http.ReadRequest(bufio.NewReader(bytes.NewReader(pkt.Payload)))
if reqErr == nil {
token = (uint32(pkt.TCP.SrcPort) << 8) + uint32(pkt.TCP.DestPort)
reqTimers[token] = ms.StartTimer("timer " + req.Method + " " + req.URL.Path)
reqVerbTimers[token] = ms.StartTimer("verbtimer " + req.Method)
globalTimers[token] = ms.StartTimer("globaltimer")
ms.Histogram("size "+req.Method+" "+req.URL.Path, float64(req.ContentLength))
ms.Counter(req.Method+" "+req.URL.Path, 1)
reqVerb[token] = req.Method
} else {
res, resErr := http.ReadResponse(bufio.NewReader(bytes.NewReader(pkt.Payload)), nil)
if resErr != nil {
// not a valid request or response
continue
}
ms.Histogram("globalsize", float64(res.ContentLength))
token = (uint32(pkt.TCP.DestPort) << 8) + uint32(pkt.TCP.SrcPort)
reqTimer, present := reqTimers[token]
if present {
reqTimer.Stop()
delete(reqTimers, token)
}
verbTimer, present := reqVerbTimers[token]
if present {
verbTimer.Stop()
delete(reqVerbTimers, token)
}
globalTimer, present := globalTimers[token]
if present {
globalTimer.Stop()
delete(globalTimers, token)
}
verb, present := reqVerb[token]
if present {
ms.Histogram("verbsize "+verb, float64(res.ContentLength))
delete(reqVerb, token)
}
}
}
}
