func readFromCollector(collector collector.Collector,
handlers []handler.Handler,
collectorStatChans ...chan<- metric.CollectorEmission) {
// In case of Diamond collectors, metric from multiple collectors are read
// from Single channel (owned by Go Diamond Collector) and hence we use a map
// for keeping track of metrics from each individual collector
emissionCounter := map[string]uint64{}
lastEmission := time.Now()
statDuration := time.Duration(collector.Interval()) * time.Second
for m := range collector.Channel() {
var exists bool
c := collector.CanonicalName()
if _, exists = m.GetDimensionValue("collector"); !exists {
m.AddDimension("collector", collector.Name())
}
// We allow external collectors to provide us their collector's CanonicalName
// by sending it as a metric dimension. For example in the case of Diamond the
// individual python collectors can send their names this way.
if val, ok := m.GetDimensionValue("collectorCanonicalName"); ok {
c = val
m.RemoveDimension("collectorCanonicalName")
}
// check if the metric is blacklisted, if so skip it and
// process the next one
if stringInSlice(m.Name, collector.Blacklist()) {
continue
}
emissionCounter[c]++
// collectorStatChans is an optional parameter. In case of ad-hoc collector
// this parameter is not supplied at all. Using variadic arguments is pretty much
// only way of doing this in go.
if len(collectorStatChans) > 0 {
collectorStatChan := collectorStatChans[0]
currentTime := time.Now()
if currentTime.After(lastEmission.Add(statDuration)) {
emitCollectorStats(emissionCounter, collectorStatChan)
lastEmission = time.Now()
}
}
if len(collector.Prefix()) > 0 {
m.Name = collector.Prefix() + m.Name
}
for i := range handlers {
if _, exists := handlers[i].CollectorEndpoints()[c]; exists {
handlers[i].CollectorEndpoints()[c].Channel <- m
}
}
}
// Closing the stat channel after collector loop finishes
for _, statChannel := range collectorStatChans {
close(statChannel)
}
}
func readFromCollector(collector collector.Collector, handlers []handler.Handler) {
for metric := range collector.Channel() {
var exists bool
c := collector.CanonicalName()
if _, exists = metric.GetDimensionValue("collector"); !exists {
metric.AddDimension("collector", collector.Name())
}
// We allow external collectors to provide us their collector's CanonicalName
// by sending it as a metric dimension. For example in the case of Diamond the
// individual python collectors can send their names this way.
if val, ok := metric.GetDimensionValue("collectorCanonicalName"); ok {
c = val
metric.RemoveDimension("collectorCanonicalName")
}
for i := range handlers {
if _, exists := handlers[i].CollectorChannels()[c]; exists {
handlers[i].CollectorChannels()[c] <- metric
}
}
}
}