A more cautious approach to securing transactions

[iugo]

A more cautious approach to securing transactions

1. Set a safe private property on the QueryClient.
2. Change safe to false every time begin() is executed on a connection.
3. Every time commit() or rollback() is executed on a connection change safe to true.

What the user has to do:

1. Determine if a connection is secure before starting a new transaction.
2. If it is not safe, you can use end() to end the connection and reconnect. You can also execute
   rollback() to roll back. Or select begin() to commit.

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更谨慎的 确保事务安全的 办法

1. 在连接上设置一个 safe 私有属性.
2. 每次在一个连接上执行 begin() 都将 safe 改为 false.
3. 每次在一个连接上执行 commit() 或者 rollback() 都将 safe 改为 true.

使用者要做的:

1. 开始新的事务之前判断一个连接是否安全.
2. 如果不安全, 可以使用 end() 结束这个连接, 重新进行连接. 也可以执行
   rollback() 进行回滚. 或者选择 begin() 进行提交.

[Soremwar]

The current approach already accomplishes this, albeit with a little more steps

if (client.session.current_transaction !== null) {
  await client.createTransaction(transaction_name).rollback();
}

I don't recommend ending the connection altogether, since that also removes whatever temporal data was created in the current session

[iugo]

.release() will resetSessionMetadata().
resetSessionMetadata() let #transaction = null(session.current_transaction is null).

If the previous client transaction rollback() failed, but release() succeeded.
It will cause the client.session.current_transaction of subsequent reuse of this client to be null.

[iugo]

maybe add .safeRelease():

safeRelease() {
  if (this.session.current_transaction !== null) {
    throw new Error('transaction ongoing');
  }
  this.release();
}