Fix for issue #250

Signed-off-by: Amit Saha <amitsaha.in@gmail.com>

bridge_test.go

@@ -157,6 +157,16 @@ func TestHandlePacket(t *testing.T) {
 					labels:     map[string]string{"tag1": "bar", "tag2": "baz"},
 				},
 			},
+		}, {
+			name: "histogram with sampling",
+			in:   "foo:0.01|h|@0.1|#tag1:bar,#tag2:baz",
+			out: Events{
+				&TimerEvent{
+					metricName: "foo",
+					value:      0.01,
+					labels:     map[string]string{"tag1": "bar", "tag2": "baz"},
+				},
+			},
 		}, {
 			name: "datadog tag extension with multiple colons",
 			in:   "foo:100|c|@0.1|#tag1:foo:bar",

exporter.go

@@ -389,8 +389,8 @@ samples:
 			for _, component := range components[2:] {
 				switch component[0] {
 				case '@':
-					if statType != "c" && statType != "ms" {
-						log.Debugln("Illegal sampling factor for non-counter metric on line", line)
+					if statType == "g" {
+						log.Debugln("Illegal sampling factor for gauge metric type on line", line)
 						sampleErrors.WithLabelValues("illegal_sample_factor").Inc()
 						continue
 					}
@@ -405,7 +405,7 @@ samples:
 
 					if statType == "c" {
 						value /= samplingFactor
-					} else if statType == "ms" {
+					} else if statType == "ms" || statType == "h" {
 						multiplyEvents = int(1 / samplingFactor)
 					}
 				case '#':