Files
go-omni/examples/transactions/demoDriver.go

49 lines
1.4 KiB
Go

package main
import (
"context"
"database/sql/driver"
"errors"
"sync/atomic"
)
// This driver models an acknowledgement lost AFTER persistence. Applications
// use their normal SQL driver; this is solely a runnable fault demonstration.
type demoConnector struct {
beginErr, commitErr, rollbackErr error
persistBeforeError bool
stored atomic.Bool
}
func (d *demoConnector) Connect(context.Context) (driver.Conn, error) {
return &demoConn{owner: d}, nil
}
func (d *demoConnector) Driver() driver.Driver { return d }
func (d *demoConnector) Open(string) (driver.Conn, error) { return d.Connect(context.Background()) }
type demoConn struct{ owner *demoConnector }
func (c *demoConn) Prepare(string) (driver.Stmt, error) {
return nil, errors.New("not implemented by demo")
}
func (c *demoConn) Close() error { return nil }
func (c *demoConn) Begin() (driver.Tx, error) {
if c.owner.beginErr != nil {
return nil, c.owner.beginErr
}
return &demoTx{owner: c.owner}, nil
}
func (c *demoConn) ExecContext(context.Context, string, []driver.NamedValue) (driver.Result, error) {
return driver.RowsAffected(1), nil
}
type demoTx struct{ owner *demoConnector }
func (tx *demoTx) Commit() error {
if tx.owner.commitErr == nil || tx.owner.persistBeforeError {
tx.owner.stored.Store(true)
}
return tx.owner.commitErr
}
func (tx *demoTx) Rollback() error { return tx.owner.rollbackErr }