Hi Edoardo, KIP-179 will support changing topic configurations via the AdminClient and this would open a loophole to avoid the current CreateTopicPolicy:
1. Create a topic that sticks to the policy 2. Modify the topic after creation to something which would have violated the policy. For this reason KIP-179 proposes to apply the create topic policy to topic modification too. If there were going to be a new "V2" interface (as opposed to changing the RequestMetadata) I think it would be beneficial if the name reflected that it applied to updates too. CreateOrAlterTopicPolicy? Though obviously that name doesn't reflect that its heritage in the original CreateTopicPolicy. Cheers, Tom On 5 September 2017 at 18:48, Edoardo Comar <edoco...@gmail.com> wrote: > Hi Ismael, > I was on leave for a long while. I will update the KIP. > > Edo > > On 5 September 2017 at 11:42, Ismael Juma <ism...@juma.me.uk> wrote: > > > Hi Edoardo, > > > > Do you intend to update the KIP to avoid the introduction of another > > interface? > > > > Ismael > > > > On Fri, Jun 23, 2017 at 5:47 PM, Edoardo Comar <eco...@uk.ibm.com> > wrote: > > > > > Thanks for the thoughts Ismael > > > > > > > 1. Have you considered extending RequestMetadata with the additional > > > > information you need? We could add Cluster to it, which has topic > > > > assignment information, for example. This way, there would be no need > > > for a > > > > V2 interface. > > > > > > 1. I hadn't thought of it - but this seems a feasible alternative. > > > > > > The XXXPolicy.RequestMetadata could be enriched to include more > > > information - > > > for backward compatibility with existing Policies we would only add > > > methods to these classes. > > > > > > Presumably the number of Admin Request is not huge so we should not be > > too > > > worried > > > about the overhead of populating a org.apache.kafka.common.Cluster for > > > every admin request , right ? > > > > > > The only feature I can't see how to easily support with the enriched > > > XXXPolicy.RequestMetadata is how to check > > > for a topic being marked for deletion using the Cluster information > > > > > > This check is useful for us in excluding such outliers when counting > the > > > number of partitions. > > > > > > > > > > 2. Something else that could be useful is passing an instance of > > > `Session` > > > > so that one can provide custom behaviour depending on the logged in > > > user. > > > > Would this be useful? > > > 2. Definitely I would expect that a general solution includes the > Session > > > or the KafkaPrincipal associated with it > > > (the latter may be a simpler dependency for the > XXXPolicy.RequestMetadata > > > > > > > > > > 3. For the delete case, we may consider passing a class instead of > just > > > a > > > > string to the validate method so that we have options if we need to > > > extend > > > > it. > > > > > > 3. Agree, we should have the DeletePolicy define its RequestMetadata > > > class, too > > > > > > > > > > 4. Do we want to enhance the AlterConfigs policy as well? > > > > > > 4. I don't see why not :-) > > > > > > > > > > > > thanks > > > Edo > > > -------------------------------------------------- > > > > > > Edoardo Comar > > > > > > IBM Message Hub > > > > > > > > > isma...@gmail.com wrote on 22/06/2017 15:05:06: > > > > > > > From: Ismael Juma <ism...@juma.me.uk> > > > > To: dev@kafka.apache.org > > > > Date: 22/06/2017 15:05 > > > > Subject: Re: [DISCUSS] KIP-170: Enhanced TopicCreatePolicy and > > > > introduction of TopicDeletePolicy > > > > Sent by: isma...@gmail.com > > > > > > > > Thanks for the KIP, Edoardo. A few comments: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Ismael > > > > > > > > On Thu, Jun 22, 2017 at 2:41 PM, Edoardo Comar <eco...@uk.ibm.com> > > > wrote: > > > > > > > > > Hi all, > > > > > > > > > > We've drafted "KIP-170: Enhanced TopicCreatePolicy and introduction > > of > > > > > TopicDeletePolicy" for discussion: > > > > > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP- > > 170%3A+Enhanced+ > > > > > TopicCreatePolicy+and+introduction+of+TopicDeletePolicy > > > > > > > > > > Please take a look. Your feedback is welcome and much needed. > > > > > > > > > > Thanks, > > > > > Edoardo > > > > > -------------------------------------------------- > > > > > Edoardo Comar > > > > > IBM Message Hub > > > > > eco...@uk.ibm.com > > > > > IBM UK Ltd, Hursley Park, SO21 2JN > > > > > Unless stated otherwise above: > > > > > IBM United Kingdom Limited - Registered in England and Wales with > > > number > > > > > 741598. > > > > > Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire > > PO6 > > > 3AU > > > > > > > > > > > Unless stated otherwise above: > > > IBM United Kingdom Limited - Registered in England and Wales with > number > > > 741598. > > > Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 > > 3AU > > > > > > > > > -- > "When the people fear their government, there is tyranny; when the > government fears the people, there is liberty." [Thomas Jefferson] >
