feat: Use databaseBackend config repace databaseEtcd

databaseBackend config contains type and url sub config, It can facilitate the expansion of other types of databases in the future.

utils/config.go

@@ -41,6 +41,14 @@ type ConfigStructure struct { // nolint: maligned
 	LogFormat              string                           `json:"logFormat"`
 	ServeInAPIMode         bool                             `json:"serveInAPIMode"`
 	DatabaseEtcd           string                           `json:"databaseEtcd"`
+	DatabaseBackend        DBConfig                         `json:"databaseBackend"`
+}
+
+// DBConfig
+type DBConfig struct {
+	Type   string `json:"type"`
+	URL    string `json:"url"`
+	DbPath string `json:"dbPath"`
 }
 
 type LocalPoolStorage struct {

utils/config_test.go

@@ -144,7 +144,11 @@ func (s *ConfigSuite) TestSaveConfig(c *C) {
 		"  \"logLevel\": \"info\",\n"+
 		"  \"logFormat\": \"json\",\n"+
 		"  \"serveInAPIMode\": false,\n"+
-		"  \"databaseEtcd\": \"\"\n"+
+		"  \"databaseEtcd\": \"\",\n"+
+		"  \"databaseBackend\": {\n"+
+		"    \"type\": \"\",\n"+
+		"    \"url\": \"\"\n"+
+		"  }\n"+
 		"}")
 }