Add autorollback functionality for database

[BurievSardor]

if adding autorollback functionality is impossible, please uncomment commit() function in transaction class.

class Transaction : public DbClient
{
public:
virtual void rollback() = 0;
// virtual void commit() = 0;
virtual void setCommitCallback(
const std::function<void(bool)> &commit Callback) = 0;
void closeAll() override
{
}
};

[hwc0919]

A transaction will rollback automatically on any query failure.

[BurievSardor]

Thank you for your answer. In drogon when the Transaction object is destructed, the commit statement is automatically executed to end the transaction. But i need the opposite. I meant this.

[hwc0919]

We could add a setAutoCommit(bool) method to make the Transaction commit or rollback in destructor. In the meantime we should uncomment the commit() method to let user commit manually.

There is also an easy solution without any changes on the library.

class TransactionAutoRollback
{
  public:
    TransactionAutoRollback(std::shared_ptr<Transaction> &&trans)
        : trans_(std::move(trans))
    {
    }
    ~TransactionAutoRollback()
    {
        if (trans_)
            trans_->rollback();
    }
    const std::shared_ptr<Transaction> &get()
    {
        return trans_;
    }
    void commit(const std::function<void(bool)> &commitCallback)
    {
        if (trans_)
        {
            if (commitCallback)
            {
                trans_->setCommitCallback(commitCallback);
            }
            trans_.reset();
        }
    }

  private:
    std::shared_ptr<Transaction> trans_;
};

[BurievSardor]

@an-tao Can we add setAutoCommit(bool) funtion for Transaction class? I really need it.