Added a /metrics handler to fetch metrics data

Right now we're writing metrics data to a file. This new handler allows others to fetch metrics data. Right now the handler only returns the counts for the last 24 hours as a temporary thing. This should be changed, depending on what the metrics team needs but definitely to include measurements from the last full 24 hour measurement period.
cohosh · Aug 9, 2019 · f0e71c7c58f72118313c28c1d90ec4fdfb74a23f · f0e71c7
1 parent 0b55fd3
commit f0e71c7c58f72118313c28c1d90ec4fdfb74a23f
Showing with 22 additions and 15 deletions.

+5 −0 broker/broker.go

+10 −8 broker/metrics.go

+7 −7 broker/snowflake-broker_test.go
diff --git a/broker/broker.go b/broker/broker.go
@@ -246,6 +246,10 @@ func debugHandler(ctx *BrokerContext, w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte(s))
 }
 
+func metricsHandler(ctx *BrokerContext, w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte(ctx.metrics.printMetrics()))
+}
+
 func robotsTxtHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
 	w.Write([]byte("User-agent: *\nDisallow: /\n"))
@@ -313,6 +317,7 @@ func main() {
 	http.Handle("/client", SnowflakeHandler{ctx, clientOffers})
 	http.Handle("/answer", SnowflakeHandler{ctx, proxyAnswers})
 	http.Handle("/debug", SnowflakeHandler{ctx, debugHandler})
+	http.Handle("/metrics", SnowflakeHandler{ctx, metricsHandler})
 
 	server := http.Server{
 		Addr: addr,

diff --git a/broker/metrics.go b/broker/metrics.go
@@ -169,18 +169,20 @@ func NewMetrics(metricsLogger *log.Logger) (*Metrics, error) {
 func (m *Metrics) logMetrics() {
 	heartbeat := time.Tick(metricsResolution)
 	for range heartbeat {
-		m.printMetrics()
+		m.logger.Print(m.printMetrics())
 		m.zeroMetrics()
 	}
 }
 
-func (m *Metrics) printMetrics() {
-	m.logger.Println("snowflake-stats-end", time.Now().UTC().Format("2006-01-02 15:04:05"), fmt.Sprintf("(%d s)", int(metricsResolution.Seconds())))
-	m.logger.Println("snowflake-ips", m.countryStats.Display())
-	m.logger.Println("snowflake-ips-total", len(m.countryStats.addrs))
-	m.logger.Println("snowflake-idle-count", binCount(m.proxyIdleCount))
-	m.logger.Println("client-denied-count", binCount(m.clientDeniedCount))
-	m.logger.Println("client-snowflake-match-count", binCount(m.clientProxyMatchCount))
+func (m *Metrics) printMetrics() string {
+	s := fmt.Sprintln("snowflake-stats-end", time.Now().UTC().Format("2006-01-02 15:04:05"), fmt.Sprintf("(%d s)", int(metricsResolution.Seconds())))
+	s += fmt.Sprintln("snowflake-ips", m.countryStats.Display())
+	s += fmt.Sprintln("snowflake-ips-total", len(m.countryStats.addrs))
+	s += fmt.Sprintln("snowflake-idle-count", binCount(m.proxyIdleCount))
+	s += fmt.Sprintln("client-denied-count", binCount(m.clientDeniedCount))
+	s += fmt.Sprintln("client-snowflake-match-count", binCount(m.clientProxyMatchCount))
+
+	return s
 }
 
 // Restores all metrics to original values

diff --git a/broker/snowflake-broker_test.go b/broker/snowflake-broker_test.go
@@ -418,7 +418,7 @@ func TestMetrics(t *testing.T) {
 			p.offerChannel <- nil
 			<-done
 
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips CA=1\nsnowflake-ips-total 1\nsnowflake-idle-count 8\nclient-denied-count 0\nclient-snowflake-match-count 0\n")
 		})
 
@@ -431,13 +431,13 @@ func TestMetrics(t *testing.T) {
 
 			clientOffers(ctx, w, r)
 
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips \nsnowflake-ips-total 0\nsnowflake-idle-count 0\nclient-denied-count 8\nclient-snowflake-match-count 0\n")
 
 			// Test reset
 			buf.Reset()
 			ctx.metrics.zeroMetrics()
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips \nsnowflake-ips-total 0\nsnowflake-idle-count 0\nclient-denied-count 0\nclient-snowflake-match-count 0\n")
 		})
 		//Test addition of client matches
@@ -458,7 +458,7 @@ func TestMetrics(t *testing.T) {
 			snowflake.answerChannel <- []byte("fake answer")
 			<-done
 
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips \nsnowflake-ips-total 0\nsnowflake-idle-count 0\nclient-denied-count 0\nclient-snowflake-match-count 8\n")
 		})
 		//Test rounding boundary
@@ -477,12 +477,12 @@ func TestMetrics(t *testing.T) {
 			clientOffers(ctx, w, r)
 			clientOffers(ctx, w, r)
 
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips \nsnowflake-ips-total 0\nsnowflake-idle-count 0\nclient-denied-count 8\nclient-snowflake-match-count 0\n")
 
 			clientOffers(ctx, w, r)
 			buf.Reset()
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips \nsnowflake-ips-total 0\nsnowflake-idle-count 0\nclient-denied-count 16\nclient-snowflake-match-count 0\n")
 		})
 
@@ -514,7 +514,7 @@ func TestMetrics(t *testing.T) {
 			p.offerChannel <- nil
 			<-done
 
-			ctx.metrics.printMetrics()
+			ctx.metrics.logger.Print(ctx.metrics.printMetrics())
 			So(buf.String(), ShouldResemble, "snowflake-stats-end "+time.Now().UTC().Format("2006-01-02 15:04:05")+" (86400 s)\nsnowflake-ips CA=1\nsnowflake-ips-total 1\nsnowflake-idle-count 8\nclient-denied-count 0\nclient-snowflake-match-count 0\n")
 		})
 	})