Don't send logs if there are no metrics

Author: daszwarc

emf/logger.go

@@ -162,6 +162,11 @@ func (l *Logger) Log() {
 		// TODO check if not empty as above?
 		metrics = append(metrics, v.metricDirective)
 	}
+
+	if len(metrics) == 0 {
+		return
+	}
+
 	l.values["_aws"] = Metadata{
 		Timestamp: l.timestamp,
 		Metrics:   metrics,

emf/logger_test.go

@@ -171,6 +171,11 @@ func TestEmf(t *testing.T) {
 			},
 			expected: "testdata/16.json",
 		},
+		{
+			name:     "no metrics set",
+			given:    func(logger *emf.Logger) {},
+			expected: "testdata/17.txt",
+		},
 	}
 
 	for _, tc := range tcs {