fix(mysql): hide password when logging DSN

modules/mysql/collect.go

@@ -90,7 +90,7 @@ func (m *MySQL) collect() (map[string]int64, error) {
 func (m *MySQL) openConnection() error {
 	db, err := sql.Open("mysql", m.DSN)
 	if err != nil {
-		return fmt.Errorf("error on opening a connection with the mysql database [%s]: %v", m.DSN, err)
+		return fmt.Errorf("error on opening a connection with the mysql database [%s]: %v", m.safeDSN, err)
 	}
 
 	db.SetConnMaxLifetime(10 * time.Minute)
@@ -100,7 +100,7 @@ func (m *MySQL) openConnection() error {
 
 	if err := db.PingContext(ctx); err != nil {
 		_ = db.Close()
-		return fmt.Errorf("error on pinging the mysql database [%s]: %v", m.DSN, err)
+		return fmt.Errorf("error on pinging the mysql database [%s]: %v", m.safeDSN, err)
 	}
 
 	m.db = db

modules/mysql/mysql.go

@@ -4,10 +4,12 @@ package mysql
 
 import (
 	"database/sql"
+	"strings"
 	"sync"
 	"time"
 
 	"github.com/blang/semver/v4"
+	"github.com/go-sql-driver/mysql"
 	_ "github.com/go-sql-driver/mysql"
 
 	"github.com/netdata/go.d.plugin/agent/module"
@@ -55,6 +57,7 @@ type MySQL struct {
 	Config `yaml:",inline"`
 
 	db        *sql.DB
+	safeDSN   string
 	version   *semver.Version
 	isMariaDB bool
 	isPercona bool
@@ -96,6 +99,15 @@ func (m *MySQL) Init() bool {
 		return false
 	}
 
+	cfg, err := mysql.ParseDSN(m.DSN)
+	if err != nil {
+		m.Errorf("error on parsing DSN: %v", err)
+		return false
+	}
+
+	cfg.Passwd = strings.Repeat("*", len(cfg.Passwd))
+	m.safeDSN = cfg.FormatDSN()
+
 	m.Debugf("using DSN [%s]", m.DSN)
 	return true
 }
@@ -125,7 +137,7 @@ func (m *MySQL) Cleanup() {
 		return
 	}
 	if err := m.db.Close(); err != nil {
-		m.Errorf("cleanup: error on closing the mysql database [%s]: %v", m.DSN, err)
+		m.Errorf("cleanup: error on closing the mysql database [%s]: %v", m.safeDSN, err)
 	}
 	m.db = nil
 }