bq. to introduce one more prefix `main.consumer.` Makes sense.
On Mon, Apr 2, 2018 at 11:06 AM, Matthias J. Sax <matth...@confluent.io> wrote: > Boyang, > > thanks a lot for the KIP. > > Couple of questions: > > > (MODIFIED) public Map<String, Object> getRestoreConsumerConfigs(final > String clientId); > > You mean that the implementation/semantics of this method changes, but > not the API itself? Might be good to add this as "comment style" instead > of "(MODIFIED)" prefix. > > > By rewriting the getRestoreConsumerConfigs() function and adding the > getGlobalConsumerConfigs() function, if one user uses > restoreConsumerPrefix() or globalConsumerPrefix() when adding new > configurations, the configs shall overwrite base consumer config. If not > specified, restore consumer and global consumer shall share the same config > with base consumer. > > While this does make sense for backward compatibility, I am wonder if it > makes the config "inheritance logic" (ie, hierarchy) too complex? We > basically introduce a second level of overwrites. It might be simpler to > not introduce this hierarchy with the cost to break backward compatibility. > > For example, config `request.timeout.ms`: > > User sets `request.timeout.ms=<user-value>` > To change it for the main consumer, user also sets > `consumer.request.timeout.ms=<consumer-value>` > > If user only wants to change the config for main consumer, but not for > global or restore consumer, user needs to add two more configs: > > `restore.consumer.request.timeout.ms=<user-value>` > and > `global.consumer.request.timeout.ms=<user-value>` > > to reset both back to the default config. IMHO, this is not an optimal > user experience. Thus, it might be worth to change the semantics for > `consumer.` prefix to only apply those configs to the main consumer. > > > Not sure what other think what the better solution is (I am not sure by > myself to be honest---just wanted to point it out and discuss the > pros/cons for both). > > > Another though would be, to introduce one more prefix `main.consumer.` > -- using this, the existing `consumer.` prefix would apply to all > consumers (keeping it's current semantics) while we have overwrites for > all three consumers -- this allow to directly set `main.consumer` > instead of `consumer` avoiding the weird pattern from my example above > and preserves backward compatibility. Ie, if we introduce an hierarchy > of overwrite, a "full" hierarchy might be better than a "partial" > hierarchy. > > > Looking forward to your thoughts. > > > -Matthias > > > On 4/1/18 5:55 PM, Guozhang Wang wrote: > > Thanks for the KIP Boyang, the KIP looks good to me. > > > > For config values, we use underscore for keeping a single word; for > config > > keys, though, we do not use underscores or dashes. I'd suggest using dots > > to be consistent with others. > > > > > > Otherwise I'm +1 on the KIP. > > > > > > Guozhang > > > > > > On Sun, Apr 1, 2018 at 10:56 AM, Ted Yu <yuzhih...@gmail.com> wrote: > > > >> Looks good overall. > >> > >> public static final String RESTORE_CONSUMER_PREFIX = > "restore-consumer."; > >> > >> For other constants in StreamsConfig, underscore is used instead of > dash. > >> > >> Cheers > >> > >> On Sun, Apr 1, 2018 at 9:38 AM, Boyang Chen <bche...@outlook.com> > wrote: > >> > >>> Hey friends, > >>> > >>> > >>> I would like to start a discussion thread for KIP 276: > >>> > >>> https://cwiki.apache.org/confluence/display/KAFKA/KIP- > >>> 276+Add+StreamsConfig+prefix+for+different+consumers > >>> > >>> > >>> And pull request is here: > >>> > >>> https://github.com/apache/kafka/pull/4805 > >>> > >>> [https://avatars3.githubusercontent.com/u/5845561?s=400&v=4]<https:// > >>> github.com/apache/kafka/pull/4805> > >>> > >>> KAFKA-6657: Add StreamsConfig prefix for different consumers by > abbccdda > >> · > >>> Pull Request #4805 · apache/kafka<https://github. > >>> com/apache/kafka/pull/4805> > >>> github.com > >>> This pull request is for jira 6657. The KIP proposal is here Added unit > >>> tests for new getGlobalConsumerConfigs API and make sure existing > restore > >>> consumer tests are passing. > >>> > >>> > >>> > >>> > >>> > >>> Thanks, > >>> > >>> Boyang > >>> > >> > > > > > > > >
