Merge pull request #1 from danielszwarc/log-without-any-metrics

Log without any metrics

Author: prozz

emf/logger.go

@@ -158,9 +158,15 @@ func (l *Logger) Log() {
 		metrics = append(metrics, l.defaultContext.metricDirective)
 	}
 	for _, v := range l.contexts {
-		// TODO check if not empty as above?
-		metrics = append(metrics, v.metricDirective)
+		if len(v.metricDirective.Metrics) > 0 {
+			metrics = append(metrics, v.metricDirective)
+		}
 	}
+
+	if len(metrics) == 0 {
+		return
+	}
+
 	l.values["_aws"] = Metadata{
 		Timestamp: l.timestamp,
 		Metrics:   metrics,

emf/logger_test.go

@@ -2,12 +2,11 @@ package emf_test
 
 import (
 	"bytes"
+	"github.com/kinbiko/jsonassert"
+	"github.com/prozz/aws-embedded-metrics-golang/emf"
 	"io/ioutil"
 	"os"
 	"testing"
-
-	"github.com/kinbiko/jsonassert"
-	"github.com/prozz/aws-embedded-metrics-golang/emf"
 )
 
 func TestEmf(t *testing.T) {
@@ -193,6 +192,27 @@ func TestEmf(t *testing.T) {
 			jsonassert.New(t).Assertf(buf.String(), string(f))
 		})
 	}
+
+	t.Run("no metrics set", func(t *testing.T) {
+		var buf bytes.Buffer
+		logger := emf.NewFor(&buf)
+		logger.Log()
+
+		if buf.String() != "" {
+			t.Error("Buffer not empty")
+		}
+	})
+
+	t.Run("new context, no metrics set", func(t *testing.T) {
+		var buf bytes.Buffer
+		logger := emf.NewFor(&buf)
+		logger.NewContext().Namespace("galaxy")
+		logger.Log()
+
+		if buf.String() != "" {
+			t.Error("Buffer not empty")
+		}
+	})
 }
 
 func setenv(t *testing.T, env map[string]string) {

go.sum

@@ -1,4 +1,2 @@
-git.naspersclassifieds.com/Pawel.Rozynek/aws-embedded-metrics-golang v0.0.0-20200605204858-b8ba9d02bc89 h1:CBLZZgcGL8VUl9+N8t71yZgMF16Qwk4i5l7Lw1LafQY=
-git.naspersclassifieds.com/Pawel.Rozynek/aws-embedded-metrics-golang v0.0.0-20200605204858-b8ba9d02bc89/go.mod h1:GLqH9LFDevA5Hss5EuOU+N77htYcG4/d3X2JMMo9yUY=
 github.com/kinbiko/jsonassert v1.0.1 h1:8gdLmUaPWuxk2TzQSofKRqatFH6zwTF6AsUH4bugJYY=
 github.com/kinbiko/jsonassert v1.0.1/go.mod h1:QRwBwiAsrcJpjw+L+Q4WS8psLxuUY+HylVZS/4j74TM=