feat(cloud-sql): add lazy refresh for csql: mysql, sql server and postgres (#5138)

* feat: add lazy refresh for csql: mysql, sql server and postgres


---------

Co-authored-by: Eric Schmidt <[email protected]>
Co-authored-by: Jack Wotherspoon <[email protected]>

Author: 3 people

cloudsql/mysql/database-sql/connect_connector.go

@@ -47,7 +47,11 @@ func connectWithConnector() (*sql.DB, error) {
 		usePrivate             = os.Getenv("PRIVATE_IP")
 	)
 
-	d, err := cloudsqlconn.NewDialer(context.Background())
+	// WithLazyRefresh() Option is used to perform refresh
+	// when needed, rather than on a scheduled interval.
+	// This is recommended for serverless environments to
+	// avoid background refreshes from throttling CPU.
+	d, err := cloudsqlconn.NewDialer(context.Background(), cloudsqlconn.WithLazyRefresh())
 	if err != nil {
 		return nil, fmt.Errorf("cloudsqlconn.NewDialer: %w", err)
 	}

cloudsql/mysql/database-sql/connect_connector_iam_authn.go

@@ -47,7 +47,15 @@ func connectWithConnectorIAMAuthN() (*sql.DB, error) {
 		usePrivate             = os.Getenv("PRIVATE_IP")
 	)
 
-	d, err := cloudsqlconn.NewDialer(context.Background(), cloudsqlconn.WithIAMAuthN())
+	// WithLazyRefresh() Option is used to perform refresh
+	// when needed, rather than on a scheduled interval.
+	// This is recommended for serverless environments to
+	// avoid background refreshes from throttling CPU.
+	d, err := cloudsqlconn.NewDialer(
+		context.Background(),
+		cloudsqlconn.WithIAMAuthN(),
+		cloudsqlconn.WithLazyRefresh(),
+	)
 	if err != nil {
 		return nil, fmt.Errorf("cloudsqlconn.NewDialer: %w", err)
 	}

cloudsql/postgres/database-sql/connect_connector.go

@@ -57,6 +57,11 @@ func connectWithConnector() (*sql.DB, error) {
 	if usePrivate != "" {
 		opts = append(opts, cloudsqlconn.WithDefaultDialOptions(cloudsqlconn.WithPrivateIP()))
 	}
+	// WithLazyRefresh() Option is used to perform refresh
+	// when needed, rather than on a scheduled interval.
+	// This is recommended for serverless environments to
+	// avoid background refreshes from throttling CPU.
+	opts = append(opts, cloudsqlconn.WithLazyRefresh())
 	d, err := cloudsqlconn.NewDialer(context.Background(), opts...)
 	if err != nil {
 		return nil, err

cloudsql/postgres/database-sql/connect_connector_iam_authn.go

@@ -47,7 +47,15 @@ func connectWithConnectorIAMAuthN() (*sql.DB, error) {
 		usePrivate             = os.Getenv("PRIVATE_IP")
 	)
 
-	d, err := cloudsqlconn.NewDialer(context.Background(), cloudsqlconn.WithIAMAuthN())
+	// WithLazyRefresh() Option is used to perform refresh
+	// when needed, rather than on a scheduled interval.
+	// This is recommended for serverless environments to
+	// avoid background refreshes from throttling CPU.
+	d, err := cloudsqlconn.NewDialer(
+		context.Background(),
+		cloudsqlconn.WithIAMAuthN(),
+		cloudsqlconn.WithLazyRefresh(),
+	)
 	if err != nil {
 		return nil, fmt.Errorf("cloudsqlconn.NewDialer: %w", err)
 	}

cloudsql/sqlserver/database-sql/connect_connector.go

@@ -67,7 +67,11 @@ func connectWithConnector() (*sql.DB, error) {
 	if err != nil {
 		return nil, fmt.Errorf("mssql.NewConnector: %w", err)
 	}
-	dialer, err := cloudsqlconn.NewDialer(context.Background())
+	// WithLazyRefresh() Option is used to perform refresh
+	// when needed, rather than on a scheduled interval.
+	// This is recommended for serverless environments to
+	// avoid background refreshes from throttling CPU.
+	dialer, err := cloudsqlconn.NewDialer(context.Background(), cloudsqlconn.WithLazyRefresh())
 	if err != nil {
 		return nil, fmt.Errorf("cloudsqlconn.NewDailer: %w", err)
 	}