Extracted tap config to consistent volume (#617)

agent/pkg/providers/tapConfig/tap_config_provider.go

@@ -0,0 +1,54 @@
+package tapConfig
+
+import (
+	"encoding/json"
+	"github.com/up9inc/mizu/shared"
+	"github.com/up9inc/mizu/shared/logger"
+	"io/ioutil"
+	"mizuserver/pkg/models"
+	"os"
+	"sync"
+)
+
+const FilePath = shared.DataDirPath + "tap-config.json"
+
+var lock = &sync.Mutex{}
+
+var config *models.TapConfig
+
+func Get() *models.TapConfig {
+	if config == nil {
+		lock.Lock()
+		defer lock.Unlock()
+
+		if config == nil {
+			if content, err := ioutil.ReadFile(FilePath); err != nil {
+				config = &models.TapConfig{TappedNamespaces: make(map[string]bool)}
+				if !os.IsNotExist(err) {
+					logger.Log.Errorf("Error loading tap config from file, err: %v", err)
+				}
+			} else {
+				if err = json.Unmarshal(content, &config); err != nil {
+					config = &models.TapConfig{TappedNamespaces: make(map[string]bool)}
+					logger.Log.Errorf("Error while unmarshal tap config, err: %v", err)
+				}
+			}
+		}
+	}
+
+	return config
+}
+
+func Save(tapConfigToSave *models.TapConfig) {
+	lock.Lock()
+	defer lock.Unlock()
+
+	config = tapConfigToSave
+	if data, err := json.Marshal(config); err != nil {
+		logger.Log.Errorf("Error while marshal tap config, err: %v", err)
+	} else {
+		if err := ioutil.WriteFile(FilePath, data, 0644); err != nil {
+			logger.Log.Errorf("Error writing tap config to file, err: %v", err)
+		}
+	}
+}