On 27.03.21 07:37, Amit Kapila wrote:
Isn't it better to send prepare from the publisher in such a case so that subscribers can know about it when rollback prepared arrives?
That's exactly what this callback allows (among other options). It provides a way for the output plugin to react to a transaction aborting while it is being decoded. This would not be possible without this additional callback.
Also note that I would like to retain the option to do some basic protocol validity checks. Certain messages only make sense within a transaction ('U'pdate, 'C'ommit). Others are only valid outside of a transaction ('B'egin, begin_prepare_cb). This is only possible if the output plugin has a callback for every entry into and exit out of a transaction (being decoded). This used to be the case prior to 2PC decoding and this patch re-establishes that.
I think we have already done the same (sent prepare, exactly to handle the case you have described above) for *streamed* transactions.
Where can I find that? ISTM streaming transactions have the same issue: the output plugin does not (or only implicitly) learn about a concurrent abort of the transaction.
Regards Markus
