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

detector/exploitdb.go

@@ -9,33 +9,73 @@ import (
 	"time"
 
 	"github.com/cenkalti/backoff"
+	"github.com/parnurzeal/gorequest"
+	"golang.org/x/xerrors"
+
 	"github.com/future-architect/vuls/config"
 	"github.com/future-architect/vuls/logging"
 	"github.com/future-architect/vuls/models"
 	"github.com/future-architect/vuls/util"
-	"github.com/parnurzeal/gorequest"
 	exploitdb "github.com/vulsio/go-exploitdb/db"
 	exploitmodels "github.com/vulsio/go-exploitdb/models"
-
-	"golang.org/x/xerrors"
+	exploitlog "github.com/vulsio/go-exploitdb/util"
 )
 
+// goExploitDBClient is a DB Driver
+type goExploitDBClient struct {
+	driver  exploitdb.DB
+	baseURL string
+}
+
+// closeDB close a DB connection
+func (client goExploitDBClient) closeDB() error {
+	if client.driver == nil {
+		return nil
+	}
+	return client.driver.CloseDB()
+}
+
+func newGoExploitDBClient(cnf config.VulnDictInterface, o logging.LogOpts) (*goExploitDBClient, error) {
+	if err := exploitlog.SetLogger(o.LogToFile, o.LogDir, o.Debug, o.LogJSON); err != nil {
+		return nil, xerrors.Errorf("Failed to set go-exploitdb logger. err: %w", err)
+	}
+
+	db, err := newExploitDB(cnf)
+	if err != nil {
+		return nil, xerrors.Errorf("Failed to newExploitDB. err: %w", err)
+	}
+	return &goExploitDBClient{driver: db, baseURL: cnf.GetURL()}, nil
+}
+
 // FillWithExploit fills exploit information that has in Exploit
-func FillWithExploit(r *models.ScanResult, cnf config.ExploitConf) (nExploitCve int, err error) {
-	if cnf.IsFetchViaHTTP() {
+func FillWithExploit(r *models.ScanResult, cnf config.ExploitConf, logOpts logging.LogOpts) (nExploitCve int, err error) {
+	client, err := newGoExploitDBClient(&cnf, logOpts)
+	if err != nil {
+		return 0, xerrors.Errorf("Failed to newGoExploitDBClient. err: %w", err)
+	}
+	defer func() {
+		if err := client.closeDB(); err != nil {
+			logging.Log.Errorf("Failed to close DB. err: %+v", err)
+		}
+	}()
+
+	if client.driver == nil {
 		var cveIDs []string
 		for cveID := range r.ScannedCves {
 			cveIDs = append(cveIDs, cveID)
 		}
-		prefix, _ := util.URLPathJoin(cnf.GetURL(), "cves")
+		prefix, err := util.URLPathJoin(client.baseURL, "cves")
+		if err != nil {
+			return 0, xerrors.Errorf("Failed to join URLPath. err: %w", err)
+		}
 		responses, err := getExploitsViaHTTP(cveIDs, prefix)
 		if err != nil {
-			return 0, err
+			return 0, xerrors.Errorf("Failed to get Exploits via HTTP. err: %w", err)
 		}
 		for _, res := range responses {
 			exps := []exploitmodels.Exploit{}
 			if err := json.Unmarshal([]byte(res.json), &exps); err != nil {
-				return 0, err
+				return 0, xerrors.Errorf("Failed to unmarshal json. err: %w", err)
 			}
 			exploits := ConvertToModelsExploit(exps)
 			v, ok := r.ScannedCves[res.request.cveID]
@@ -46,25 +86,13 @@ func FillWithExploit(r *models.ScanResult, cnf config.ExploitConf) (nExploitCve
 			nExploitCve++
 		}
 	} else {
-		driver, locked, err := newExploitDB(&cnf)
-		if locked {
-			return 0, xerrors.Errorf("SQLite3 is locked: %s", cnf.GetSQLite3Path())
-		} else if err != nil {
-			return 0, err
-		}
-		defer func() {
-			if err := driver.CloseDB(); err != nil {
-				logging.Log.Errorf("Failed to close DB. err: %+v", err)
-			}
-		}()
-
 		for cveID, vuln := range r.ScannedCves {
 			if cveID == "" {
 				continue
 			}
-			es, err := driver.GetExploitByCveID(cveID)
+			es, err := client.driver.GetExploitByCveID(cveID)
 			if err != nil {
-				return 0, err
+				return 0, xerrors.Errorf("Failed to get Exploits by CVE-ID. err: %w", err)
 			}
 			if len(es) == 0 {
 				continue
@@ -203,19 +231,20 @@ func httpGetExploit(url string, req exploitRequest, resChan chan<- exploitRespon
 	}
 }
 
-func newExploitDB(cnf config.VulnDictInterface) (driver exploitdb.DB, locked bool, err error) {
+func newExploitDB(cnf config.VulnDictInterface) (driver exploitdb.DB, err error) {
 	if cnf.IsFetchViaHTTP() {
-		return nil, false, nil
+		return nil, nil
 	}
 	path := cnf.GetURL()
 	if cnf.GetType() == "sqlite3" {
 		path = cnf.GetSQLite3Path()
 	}
-	if driver, locked, err = exploitdb.NewDB(cnf.GetType(), path, cnf.GetDebugSQL(), exploitdb.Option{}); err != nil {
+	driver, locked, err := exploitdb.NewDB(cnf.GetType(), path, cnf.GetDebugSQL(), exploitdb.Option{})
+	if err != nil {
 		if locked {
-			return nil, true, xerrors.Errorf("exploitDB is locked. err: %w", err)
+			return nil, xerrors.Errorf("Failed to init exploit DB. SQLite3: %s is locked. err: %w", cnf.GetSQLite3Path(), err)
 		}
-		return nil, false, err
+		return nil, xerrors.Errorf("Failed to init exploit DB. DB Path: %s, err: %w", path, err)
 	}
-	return driver, false, nil
+	return driver, nil
 }