Hello, thanks for the KIP! After going through the KIP and discussion here
are some initial comments.
107 - I understand we’re proposing a new
ProducerRetriableTransactionException, and changing existing exceptions to
inherit from it (the ones on the table below it). The existing exceptions
inherit from RetriableException today, but with this KIP, they would
inherit from ProducerRetriableTransactionException which is not a
RetriableException ("*ProducerRetriableTransactionException extends
ApiException"*). Is my understanding correct? Wouldn’t this break
applications that could be handling/expecting RetriableExceptions today?
(Ie. apps dealing with TimeoutException on send , if they have
catch(RetriableException) or checks in the form of instanceOf
RetriableException, would need to change to the new
ProducerRetriableTransactionException or the specific TimeoutException,
right?). I get this wouldn’t bring a problem for most of the retriable
exceptions on the table given that they end up being handled/retried
internally, but TimeoutException is tricky.
108 - Regarding how we limit the scope of the change to the
producer/transactional API. TimeoutException is not only used in the
transactional API, but also in the consumer API, propagated to the user in
multiple api calls. Not clear to me how with this proposal we wouldn’t end
up with a consumer throwing a TimeoutException instanceOf
ProducerRetriableTransactionException? (Instead of instanceOf
RetriableException like it is today)? Again, potentially breaking apps but
also with a conceptually wrong consumer error?
109 - Similar to above, for exceptions like
UnknownTopicOrPartitionException, which are today instanceOf
RetriableException, if we’re saying they will be subclass of
ProducerRefreshRetriableTransactionException (ApiException) that will
affect the consumer logic too, where we do handle RetriableExceptions like
the unknownTopic, expecting RetriableException. This is all internal logic
and could be updated as needed of course, but without leaking
producer-specific groupings into the consumer I would expect.
110 - The KIP refers to the existing TransactionAbortableException (from
KIP-890), but on the public changes it refers to class
AbortableTransactionException extends ApiException. So are we proposing a
new exception type for this or reusing the existing one?
111 - I notice the proposed new exceptions, even though they seem like
abstract groupings, are not defined as "abstract". Is it intentional to
allow creation of instances of those?
Best!
Lianet
On Thu, Sep 12, 2024 at 6:26 AM Kaushik Raina <kra...@confluent.io.invalid>
wrote:
> Thanks for review Matthias
>
> 100/101 - Updated in KIP
>
> 104 - Added explicitly
> `For Producer-Retriable errors, the producer handles retries internally,
> keeping the failure details hidden from the application. Conversely, other
> types of exceptions will be surfaced to the application code for handling.`
>
> 105 - Grouped default exceptions explicitly
> `We will handle all default exceptions as generic unknown errors, which
> will be application recoverable. Below are few such exceptions:`
>
>
> On Sat, Aug 31, 2024 at 4:27 AM Matthias J. Sax <mj...@apache.org> wrote:
>
> > Thanks for updating the KIP. It's much clearer now what you propose. I
> > have a bunch of question about the proposal:
> >
> >
> >
> > (100) nit (typo / missing word?):
> >
> > > We would new error types
> >
> >
> >
> > (101) `TransactionAbortableException`, `ProducerFencedException`, and
> > `UnknownProducerIdException` are listed twice in the tables.
> >
> >
> >
> > (102) You introduce a new exception `AbortableTransactionException`
> > which will only be extended by `TransactionAbortableException`. Given
> > that the existing TransactionAbortableException is not thrown by the
> > producer right now (no passed into the `Callback`), it seem if the
> > producer starts to throw/return the exiting
> > `TransactionAbortableException` or the new
> > `AbortableTransactionException` is would be an incompatible change?
> >
> >
> >
> > (103) It's unclear which method would throw the new
> > `AbortableTransactionException` and/or if this new exception might be
> > passe into the producer's send `Callback`.
> >
> >
> >
> > Btw: KIP-890 does not mention `TransactionAbortableException`... Does
> > KIP-890 need an update? KIP-890 only mentions a new error code
> > TRANSACTION_ABORTABLE -- or is this an implicit introduction of
> > TransactionAbortableException -- I am not familiar with the details how
> > core KIPs are written?
> >
> >
> >
> > (104) The KIP does not explicitly say, which of the new exceptions are
> > actually user facing? It seems only AbortableTransactionException,
> > ApplicationRecoverableTransactionException, and
> > InvalidConfiguationTransactionException are exception which user will be
> > able to catch (or handle vie the `Callback`), while
> > ProducerRetriableTransactionException and
> > ProducerRefreshRetriableTransactionException won't be thrown/return by
> > the producer into the app code?
> >
> >
> >
> > (105) `IllegalStateException` and `RuntimeException` which are Java
> > exceptions are listed in the table of
> > `ApplicationRecoverableTransactionException`: I think it is not valid to
> > list them, as we cannot change their super-class.
> >
> >
> >
> > (106) `UnknownMemberIdException`, `IllegalGenerationException`, and
> > `CorrelationIdMismatchException` are listed in the table of
> > `ApplicationRecoverableTransactionException` but it seems they are not
> > thrown/returned by the producer atm. If we start to throw/return either
> > of them it seem to be a backward incompatible change.
> >
> >
> >
> > (106) Similarly to 105, `InvalidRecordException` and
> > `InvalidRequiredAcksException` are listed in the table of
> > `InvalidConfiguationTransactionException` but they seem not to be user
> > facing.
> >
> >
> >
> >
> > -Matthias
> >
> >
> > On 7/25/24 8:50 AM, Kaushik Raina wrote:
> > > Additionally,
> > > - We will be depreciating KIP-691 in favour of KIP-1050.
> > >
> > >
> > > On Fri, Jun 21, 2024 at 12:20 PM Kaushik Raina <kra...@confluent.io>
> > wrote:
> > >
> > >> Thanks Matthias for feedback
> > >> - We have updates KIP and grouped exceptions
> > >>
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-1050%3A+Consistent+error+handling+for+Transactions#KIP1050:ConsistenterrorhandlingforTransactions-ExceptionTable
> > >>
> > >> - Regarding compatibility, all changes in KIP are expected to be
> > *backword
> > >> compatible*. We have updated KIP to make it clear.
> > >>
> > >>
> > >> On Tue, Jun 11, 2024 at 4:50 AM Matthias J. Sax <mj...@apache.org>
> > wrote:
> > >>
> > >>> Thanks for this KIP. Great to see it. I would assume it will make
> > >>> KIP-691 unnecessary?
> > >>>
> > >>> I don't think I fully understand the proposal yet. It's clear, that
> you
> > >>> propose to add new sub-classed to group existing exceptions. But it's
> > >>> not clear to me, which of the existing exceptions (which implement
> > >>> ApiException directly right now) will get a new parent class and go
> > into
> > >>> the same group. You only list `InvalidProducerEpochException` which
> > gets
> > >>> `AbortableTransactionException` as new parent. It would help a lot,
> if
> > >>> you could list out explicitly, which existing exceptions are grouped
> > >>> together via which sub-class.
> > >>>
> > >>> It should be sufficient to just add a list for each group. For the
> > newly
> > >>> added exception classes, I would also omit all constructors etc and
> > just
> > >>> add a comment about it -- having constructors listed out does not add
> > >>> much value to the KIP itself but makes it harder to read (it's
> > >>> effectively noise we can avoid IMHO).
> > >>>
> > >>>
> > >>>
> > >>> I am also wondering about compatibility? If I read the section
> > >>> correctly, you actually propose to introduce a
> non-backward-compatible
> > >>> change?
> > >>>
> > >>>> Based on type of exception thrown, user needs to change their
> > exception
> > >>> catching logic to take actions against their exception handling.
> > >>>
> > >>> Ie, an application cannot be upgrade w/o code changes? I am not sure
> if
> > >>> this is acceptable?
> > >>>
> > >>> I think it would be much better (not sure if feasible) to keep the
> old
> > >>> behavior and let users opt-in / enable the new semantics via a
> config.
> > >>> If the new behavior is disabled, we could log a WARN that the app
> > should
> > >>> upgrade to work with the new semantics, and we would only enforce the
> > >>> new behavior in a later major release.
> > >>>
> > >>> Thoughts?
> > >>>
> > >>>
> > >>>
> > >>> -Matthias
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >>> On 6/7/24 4:06 AM, Kaushik Raina wrote:
> > >>>> Thank you Andrew for feedback
> > >>>>
> > >>>> 1. We are suggesting to only update subclasses of
> > >>>> o.a.k.common.errors.ApiException, which are used in transactions.
> All
> > >>> such
> > >>>> subclasses are mentioned in Exception table
> > >>>> <
> > >>>
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-1050%3A+Consistent+error+handling+for+Transactions#KIP1050:ConsistenterrorhandlingforTransactions-ExceptionTable
> > >>>>
> > >>>>
> > >>>> 2. "Producer-Recoverable" corresponds to the AbortableException. I
> > have
> > >>>> updated comments on each exception type.
> > >>>>
> > >>>> 3. Yes, it's correct that by adding a "Retriable" exception, it
> > >>> simplifies
> > >>>> the determination of which errors can be retried internally. In the
> > >>> Exception
> > >>>> table
> > >>>> <
> > >>>
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-1050%3A+Consistent+error+handling+for+Transactions#KIP1050:ConsistenterrorhandlingforTransactions-ExceptionTable
> > >>>>
> > >>>> mentioned
> > >>>> in the "Proposed Changes" section, the "Expected Handling" column
> > >>> signifies
> > >>>> the handling for each error type. Please let me know if any further
> > >>>> clarification is needed.
> > >>>>
> > >>>> 4a. Yes, that is correct. For clarity, only one constructor has been
> > >>>> mentioned in the KIP. An ellipsis has been added as a placeholder,
> > >>>> indicating that there are additional functions in the class but they
> > are
> > >>>> not explicitly specified.
> > >>>> 4b. Updated in the KIP.
> > >>>>
> > >>>> 5. TopicAuthorizationException extends "Invalid Configuration".
> > "Invalid
> > >>>> Configuration" type can be resolved either by dynamically updating
> the
> > >>>> configuration, which does not require a restart, or by statically
> > >>> updating
> > >>>> it by restarting the application. It is at the application's
> > discretion
> > >>> how
> > >>>> they want to handle each "Invalid Configuration" type.
> > >>>>
> > >>>> I have added Client side handling example
> > >>>> <
> > >>>
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-1050%3A+Consistent+error+handling+for+Transactions#KIP1050:ConsistenterrorhandlingforTransactions-Clientsidecodeexample
> > >>>>
> > >>>> in
> > >>>> KIP. Hope that helps.
> > >>>>
> > >>>
> > >>
> > >
> >
>
