configs: check that config doesn't contain extra fields

Signed-off-by: Andrey Vagin <avagin@openvz.org>

configs/config_test.go

@@ -2,6 +2,7 @@ package configs
 
 import (
 	"encoding/json"
+	"fmt"
 	"os"
 	"path/filepath"
 	"testing"
@@ -43,6 +44,34 @@ func loadConfig(name string) (*Config, error) {
 		return nil, err
 	}
 
+	// Check that a config doesn't contain extra fields
+	var configMap, abstractMap map[string]interface{}
+
+	if _, err := f.Seek(0, 0); err != nil {
+		return nil, err
+	}
+
+	if err := json.NewDecoder(f).Decode(&abstractMap); err != nil {
+		return nil, err
+	}
+
+	configData, err := json.Marshal(&container)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := json.Unmarshal(configData, &configMap); err != nil {
+		return nil, err
+	}
+
+	for k := range configMap {
+		delete(abstractMap, k)
+	}
+
+	if len(abstractMap) != 0 {
+		return nil, fmt.Errorf("unknown fields: %s", abstractMap)
+	}
+
 	return container, nil
 }
 

sample_configs/apparmor.json

@@ -104,7 +104,6 @@
 	],
 	"mount_label": "",
 	"hostname": "nsinit",
-	"console": "",
 	"namespaces": [
 		{
 			"type": "NEWNS",

sample_configs/attach_to_bridge.json

@@ -104,7 +104,6 @@
 	],
 	"mount_label": "",
 	"hostname": "koye",
-	"console": "",
 	"namespaces": [
 		{
 			"type": "NEWNS",

sample_configs/host-pid.json

@@ -104,7 +104,6 @@
 	],
 	"mount_label": "",
 	"hostname": "nsinit",
-	"console": "",
 	"namespaces": [
 		{
 			"type": "NEWNS",

sample_configs/minimal.json

@@ -104,7 +104,6 @@
 	],
 	"mount_label": "",
 	"hostname": "nsinit",
-	"console": "",
 	"namespaces": [
 		{
 			"type": "NEWNS",

sample_configs/selinux.json

@@ -104,7 +104,6 @@
 	],
 	"mount_label": "system_u:system_r:svirt_lxc_net_t:s0:c164,c475",
 	"hostname": "nsinit",
-	"console": "",
 	"namespaces": [
 		{
 			"type": "NEWNS",

sample_configs/userns.json

@@ -104,7 +104,6 @@
 	],
 	"mount_label": "",
 	"hostname": "nsinit",
-	"console": "",
 	"namespaces": [
 		{
 			"type": "NEWNS",