diff --git a/container/container.go b/container/container.go
index a8d2708c..e7a12d82 100644
--- a/container/container.go
+++ b/container/container.go
@@ -49,6 +49,7 @@ func (c *container) GetConfig() *config.Config {
 	return c.config
 }
 
+// GetMessages returns the map has key and message.
 func (c *container) GetMessages() map[string]string {
 	return c.messages
 }
diff --git a/go.mod b/go.mod
index e59ebbf0..ef8bdaa8 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/ybkuroki/go-webapp-sample
 
-go 1.19
+go 1.20
 
 require (
 	github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751
diff --git a/main.go b/main.go
index 8ee9be3a..1e3e667e 100644
--- a/main.go
+++ b/main.go
@@ -40,7 +40,7 @@ var propsFile embed.FS
 func main() {
 	e := echo.New()
 
-	messages := util.ReadPropertiesFile(propsFile)
+	messages := util.ReadPropertiesFile(propsFile, "messages.properties")
 	conf, env := config.Load(yamlFile)
 	logger := logger.InitLogger(env, zapYamlFile)
 	logger.GetZapLogger().Infof("Loaded this configuration : application." + env + ".yml")
diff --git a/util/props.go b/util/props.go
index 8f968703..37ba950b 100644
--- a/util/props.go
+++ b/util/props.go
@@ -12,10 +12,10 @@ const (
 )
 
 // ReadPropertiesFile reads a properties file and it returns a map has the keys and values in the file.
-func ReadPropertiesFile(fs embed.FS) map[string]string {
+func ReadPropertiesFile(fs embed.FS, fileName string) map[string]string {
 	config := make(map[string]string)
 
-	file, err := fs.Open("messages.properties")
+	file, err := fs.Open(fileName)
 	if err != nil {
 		return nil
 	}
diff --git a/util/props_test.go b/util/props_test.go
new file mode 100644
index 00000000..93019f4f
--- /dev/null
+++ b/util/props_test.go
@@ -0,0 +1,22 @@
+package util
+
+import (
+	"embed"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+//go:embed test.properties
+var testPropsFile embed.FS
+
+func TestReadPropertiesFile(t *testing.T) {
+	messages := ReadPropertiesFile(testPropsFile, "test.properties")
+
+	assert.Equal(t, "testtest", messages["props1"])
+	assert.Equal(t, "test test", messages["props2"])
+	assert.Equal(t, "", messages["props3"])
+	_, ok := messages["props4"]
+	assert.Equal(t, false, ok)
+	assert.Equal(t, "test #test", messages["props5"])
+}
diff --git a/util/test.properties b/util/test.properties
new file mode 100644
index 00000000..7f53d0c4
--- /dev/null
+++ b/util/test.properties
@@ -0,0 +1,7 @@
+# comment line
+props1=testtest
+props2 = test test
+props3=
+# comment line
+props4
+props5= test #test