Respect errors returned on 'json.Marshal()' to prevent unexpected panic

.gitignore

@@ -1,2 +1,4 @@
 .coverprofile
 /bin
+# GoLand
+.idea

log/logger.go

@@ -61,15 +61,24 @@ type LineJSONDev struct {
 func (l Line) MarshalJSON() ([]byte, error) {
 	lineTemp := LineJSON(l)
 
-	lineValue, _ := json.Marshal(lineTemp)
+	lineValue, err := json.Marshal(lineTemp)
+	if err != nil {
+		return nil, err
+	}
 	verbosity, errConvert := strconv.Atoi(l.Verbosity)
 	if verbosity > 1 && errConvert == nil {
 		lineTempDev := LineJSONDev(l)
-		lineValue, _ = json.Marshal(lineTempDev)
+		lineValue, err = json.Marshal(lineTempDev)
+		if err != nil {
+			return nil, err
+		}
 	}
 	lineValue = lineValue[1 : len(lineValue)-1]
 
-	contextValue, _ := json.Marshal(lineTemp.Context)
+	contextValue, err := json.Marshal(lineTemp.Context)
+	if err != nil {
+		return nil, err
+	}
 	contextValue = contextValue[1 : len(contextValue)-1]
 
 	sep := ""

log/logger_test.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"math"
 	"reflect"
 	"testing"
 
@@ -44,6 +45,42 @@ func TestLogger_Error_noKeysAndValues(t *testing.T) {
 	require.EqualValues(t, err, logs[0].Error)
 }
 
+var unsupportedValues = []float64{
+	math.NaN(),
+	math.Inf(-1),
+	math.Inf(1),
+}
+
+func TestLogger_Info_UnsupportedValues(t *testing.T) {
+	for _, unsupportedValue := range unsupportedValues {
+		buf := bytes.NewBuffer(nil)
+		logger := log.NewLogger("", buf, 0, log.JSONEncoder{})
+		logger.Info("Test unsupported value", "value", unsupportedValue)
+
+		if buf.Len() == 0 {
+			t.Fatal("expected log output, but buffer was empty")
+		}
+		assert.Contains(t, string(buf.Bytes()), "failed to encode message")
+		assert.Contains(t, string(buf.Bytes()), fmt.Sprintf("json: unsupported value: %f", unsupportedValue))
+	}
+}
+
+func TestLogger_Error_UnsupportedValues(t *testing.T) {
+	for _, unsupportedValue := range unsupportedValues {
+		buf := bytes.NewBuffer(nil)
+		logger := log.NewLogger("", buf, 0, log.JSONEncoder{})
+		err := kverrors.New("an error")
+		logger.Error(err, "Test unsupported value", "key", unsupportedValue)
+
+		if buf.Len() == 0 {
+			t.Fatal("expected log output, but buffer was empty")
+		}
+		println(string(buf.Bytes()))
+		assert.Contains(t, string(buf.Bytes()), "failed to encode message")
+		assert.Contains(t, string(buf.Bytes()), fmt.Sprintf("json: unsupported value: %f", unsupportedValue))
+	}
+}
+
 func TestLogger_Error_KeysAndValues(t *testing.T) {
 	obs, logger := NewObservedLogger()