diff --git a/proxy/common/config/json/config_cache.go b/proxy/common/config/json/config_cache.go
index 1e1a0f909..957d74d78 100644
--- a/proxy/common/config/json/config_cache.go
+++ b/proxy/common/config/json/config_cache.go
@@ -7,7 +7,7 @@ import (
 type ConfigObjectCreator func() interface{}
 
 var (
-	configCache = make(map[string]ConfigObjectCreator)
+	configCache map[string]ConfigObjectCreator
 )
 
 func getConfigKey(protocol string, cType config.Type) string {
@@ -35,3 +35,11 @@ func CreateConfig(protocol string, cType config.Type) interface{} {
 	}
 	return creator()
 }
+
+func initializeConfigCache() {
+	configCache = make(map[string]ConfigObjectCreator)
+}
+
+func init() {
+	initializeConfigCache()
+}
diff --git a/proxy/common/config/json/config_cache_test.go b/proxy/common/config/json/config_cache_test.go
new file mode 100644
index 000000000..7ac3574ff
--- /dev/null
+++ b/proxy/common/config/json/config_cache_test.go
@@ -0,0 +1,46 @@
+package json
+
+import (
+	"testing"
+
+	"github.com/v2ray/v2ray-core/proxy/common/config"
+	"github.com/v2ray/v2ray-core/testing/unit"
+)
+
+func TestRegisterInboundConfig(t *testing.T) {
+	assert := unit.Assert(t)
+	initializeConfigCache()
+
+	protocol := "test_protocol"
+	creator := func() interface{} {
+		return true
+	}
+
+	err := RegisterInboundConnectionConfig(protocol, creator)
+	assert.Error(err).IsNil()
+
+	configObj := CreateConfig(protocol, config.TypeInbound)
+	assert.Bool(configObj.(bool)).IsTrue()
+
+	configObj = CreateConfig(protocol, config.TypeOutbound)
+	assert.Pointer(configObj).IsNil()
+}
+
+func TestRegisterOutboundConfig(t *testing.T) {
+	assert := unit.Assert(t)
+	initializeConfigCache()
+
+	protocol := "test_protocol"
+	creator := func() interface{} {
+		return true
+	}
+
+	err := RegisterOutboundConnectionConfig(protocol, creator)
+	assert.Error(err).IsNil()
+
+	configObj := CreateConfig(protocol, config.TypeOutbound)
+	assert.Bool(configObj.(bool)).IsTrue()
+
+	configObj = CreateConfig(protocol, config.TypeInbound)
+	assert.Pointer(configObj).IsNil()
+}