feat: use custom dialer when connecting to mysql (#5609)

When connecting to mysql use the Dialer taken from the provided
Dependencies.

Author: mhilton

go.mod

@@ -19,7 +19,7 @@ require (
 	github.com/eclipse/paho.mqtt.golang v1.5.1
 	github.com/fatih/color v1.15.0
 	github.com/foxcpp/go-mockdns v0.0.0-20201212160233-ede2f9158d15
-	github.com/go-sql-driver/mysql v1.5.0
+	github.com/go-sql-driver/mysql v1.9.3
 	github.com/gofrs/uuid v3.3.0+incompatible
 	github.com/golang/geo v0.0.0-20190916061304-5b978397cfec
 	github.com/google/flatbuffers v25.9.23+incompatible
@@ -62,6 +62,7 @@ require (
 	cloud.google.com/go/iam v1.2.2 // indirect
 	cloud.google.com/go/longrunning v0.6.2 // indirect
 	cloud.google.com/go/monitoring v1.21.2 // indirect
+	filippo.io/edwards25519 v1.1.0 // indirect
 	github.com/99designs/go-keychain v0.0.0-20191008050251-8e49817e8af4 // indirect
 	github.com/99designs/keyring v1.2.2 // indirect
 	github.com/Azure/azure-sdk-for-go/sdk/internal v1.11.2 // indirect

go.sum

@@ -40,6 +40,8 @@ cloud.google.com/go/storage v1.5.0/go.mod h1:tpKbwo567HUNpVclU5sGELwQWBDZ8gh0Zeo
 cloud.google.com/go/storage v1.43.0 h1:CcxnSohZwizt4LCzQHWvBf1/kvtHUn7gk9QERXPyXFs=
 cloud.google.com/go/storage v1.43.0/go.mod h1:ajvxEa7WmZS1PxvKRq4bq0tFT3vMd502JwstCcYv0Q0=
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
+filippo.io/edwards25519 v1.1.0 h1:FNf4tywRC1HmFuKW5xopWpigGjJKiJSV0Cqo0cJWDaA=
+filippo.io/edwards25519 v1.1.0/go.mod h1:BxyFTGdWcka3PhytdK4V28tE5sGfRvvvRV7EaN4VDT4=
 github.com/99designs/go-keychain v0.0.0-20191008050251-8e49817e8af4 h1:/vQbFIOMbk2FiG/kXiLl8BRyzTWDw7gX/Hz7Dd5eDMs=
 github.com/99designs/go-keychain v0.0.0-20191008050251-8e49817e8af4/go.mod h1:hN7oaIRCjzsZ2dE+yG5k+rsdt3qcwykqK6HVGcKwsw4=
 github.com/99designs/keyring v1.2.2 h1:pZd3neh/EmUzWONb35LxQfvuY7kiSXAq3HQd97+XBn0=
@@ -197,8 +199,8 @@ github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/go-openapi/jsonpointer v0.19.5/go.mod h1:Pl9vOtqEWErmShwVjC8pYs9cog34VGT37dQOVbmoatg=
 github.com/go-openapi/swag v0.19.5/go.mod h1:POnQmlKehdgb5mhVOsnJFsivZCEZ/vjK9gh66Z9tfKk=
-github.com/go-sql-driver/mysql v1.5.0 h1:ozyZYNQW3x3HtqT1jira07DN2PArx2v7/mN66gGcHOs=
-github.com/go-sql-driver/mysql v1.5.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
+github.com/go-sql-driver/mysql v1.9.3 h1:U/N249h2WzJ3Ukj8SowVFjdtZKfu9vlLZxjPXV1aweo=
+github.com/go-sql-driver/mysql v1.9.3/go.mod h1:qn46aNg1333BRMNU69Lq93t8du/dwxI64Gl8i5p1WMU=
 github.com/goccy/go-json v0.10.5 h1:Fq85nIqj+gXn/S5ahsiTlK3TmC85qgirsdTP/+DeaC4=
 github.com/goccy/go-json v0.10.5/go.mod h1:oq7eo15ShAhp70Anwd5lgX2pLfOS3QCiwU/PULtXL6M=
 github.com/godbus/dbus v0.0.0-20190726142602-4481cbc300e2 h1:ZpnhV/YsD2/4cESfV5+Hoeu/iUR3ruzNvZ+yQfO03a0=

stdlib/sql/from_private_test.go

@@ -249,6 +249,30 @@ func TestMssqlOpenFunctionDialer(t *testing.T) {
 	}
 }
 
+func TestMysqlOpenFunctionDialer(t *testing.T) {
+	expectErr := errors.New("test dial error")
+	deps := mockDeps{
+		Deps:   flux.NewDefaultDependencies(),
+		dialer: &mockDialer{err: expectErr},
+	}
+
+	openFn := mysqlOpenFunction("username:password@tcp(localhost:3306)/dbname")
+	db, err := openFn(deps)
+	if err != nil {
+		t.Fatalf("unexpected error from open function: %v", err)
+	}
+	defer db.Close()
+
+	// Ping triggers a real connection attempt, which will use our mock dialer.
+	err = db.Ping()
+	if err == nil {
+		t.Fatal("expected error from Ping, got nil")
+	}
+	if !errors.Is(err, expectErr) {
+		t.Fatalf("expected error %q, got: %v", expectErr, err)
+	}
+}
+
 func TestFromSqliteUrlValidation(t *testing.T) {
 	testCases := executetest.SourceUrlValidationTestCases{
 		{

stdlib/sql/mysql.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/go-sql-driver/mysql"
 	"github.com/influxdata/flux"
 	"github.com/influxdata/flux/codes"
 	"github.com/influxdata/flux/execute"
@@ -197,3 +198,22 @@ func MysqlColumnTranslateFunc() translationFunc {
 func mysqlQuoteIdent(name string) string {
 	return fmt.Sprintf("`%s`", strings.ReplaceAll(name, "`", "``"))
 }
+
+func mysqlOpenFunction(dataSourceName string) openFunc {
+	return func(deps flux.Dependencies) (*sql.DB, error) {
+		cfg, err := mysql.ParseDSN(dataSourceName)
+		if err != nil {
+			return nil, err
+		}
+		dialer, err := deps.Dialer()
+		if err != nil {
+			return nil, err
+		}
+		cfg.DialFunc = dialer.DialContext
+		connector, err := mysql.NewConnector(cfg)
+		if err != nil {
+			return nil, err
+		}
+		return sql.OpenDB(connector), nil
+	}
+}

stdlib/sql/open.go

@@ -40,6 +40,8 @@ func getOpenFunc(driverName, dataSourceName string) openFunc {
 	switch driverName {
 	case "mssql", "sqlserver":
 		return mssqlOpenFunction(dataSourceName)
+	case "mysql":
+		return mysqlOpenFunction(dataSourceName)
 	case "postgres":
 		return postgresOpenFunction(dataSourceName)
 	default: