Log geoip stats of proxies by unique IP

Change it so that we log the geoip country code of proxies if they poll
within the current metrics epoch. We make sure we log by unique IP
address

broker/metrics.go

@@ -17,6 +17,7 @@ var (
 const metricsResolution = 86400 * time.Second
 
 type CountryStats struct {
+	ips    map[string]bool
 	counts map[string]int
 }
 
@@ -65,8 +66,11 @@ func (m *Metrics) UpdateCountryStats(addr string) {
 		log.Println("Unknown geoip")
 	}
 
-	//update map of countries and counts
-	m.countryStats.counts[country]++
+	//update map of unique ips and counts
+	if !m.countryStats.ips[addr] {
+		m.countryStats.counts[country]++
+		m.countryStats.ips[addr] = true
+	}
 
 	return
 }
@@ -101,6 +105,7 @@ func NewMetrics(metricsLogger *log.Logger) (*Metrics, error) {
 
 	m.countryStats = CountryStats{
 		counts: make(map[string]int),
+		ips:    make(map[string]bool),
 	}
 
 	m.logger = metricsLogger
@@ -126,6 +131,7 @@ func (m *Metrics) logMetrics() {
 		m.clientDeniedCount = 0
 		m.clientProxyMatchCount = 0
 		m.countryStats.counts = make(map[string]int)
+		m.countryStats.ips = make(map[string]bool)
 	}
 }