refactor(detector): standardize db.NewDB to db.CloseDB (#1380)

* feat(subcmds/report,server): read environment variables when configPath is ""

* refactor: standardize db.NewDB to db.CloseDB

* chore: clean up import

* chore: error wrap

* chore: update goval-dictionary

* fix(oval): return Pseudo instead of nil for client

* chore: fix comment

* fix: lint error

subcmds/report.go

@@ -175,10 +175,24 @@ func (p *ReportCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}
 	logging.Log = logging.NewCustomLogger(config.Conf.Debug, config.Conf.Quiet, config.Conf.LogToFile, config.Conf.LogDir, "", "")
 	logging.Log.Infof("vuls-%s-%s", config.Version, config.Revision)
 
-	if err := config.Load(p.configPath); err != nil {
-		logging.Log.Errorf("Error loading %s, %+v", p.configPath, err)
-		return subcommands.ExitUsageError
+	if p.configPath == "" {
+		for _, cnf := range []config.VulnDictInterface{
+			&config.Conf.CveDict,
+			&config.Conf.OvalDict,
+			&config.Conf.Gost,
+			&config.Conf.Exploit,
+			&config.Conf.Metasploit,
+			&config.Conf.KEVuln,
+		} {
+			cnf.Init()
+		}
+	} else {
+		if err := config.Load(p.configPath); err != nil {
+			logging.Log.Errorf("Error loading %s. err: %+v", p.configPath, err)
+			return subcommands.ExitUsageError
+		}
 	}
+
 	config.Conf.Slack.Enabled = p.toSlack
 	config.Conf.ChatWork.Enabled = p.toChatWork
 	config.Conf.GoogleChat.Enabled = p.toGoogleChat