Hi Thomas, I think that idea is worth looking at. As you say, if no interceptor is configured then the performance overhead should be negligible. Basically it is then up to the user to decide if he wants tomtake the performance hit. We should make sure to think about monitoring capabilities like time spent in the interceptor for records etc.
The most obvious use case I think is server side schema validation, which Confluent are also offering as part of their commercial product, but other ideas come to mind as well. Best regards, Sönke Thomas Aley <thomas.a...@ibm.com> schrieb am Di., 3. Dez. 2019, 10:45: > Hi M. Manna, > > Thank you for your feedback, any and all thoughts on this are appreciated > from the community. > > I think it is important to distinguish that there are two parts to this. > One would be a server side interceptor framework and the other would be > the interceptor implementations themselves. > > The idea would be that the Interceptor framework manifests as a plug point > in the request/response paths that by itself has negligible performance > impact as without an interceptor registered in the framework it is > essentially a no-op. This way the out-the-box behavior of the Kafka broker > remains essentially unchanged, it is only if the cluster administrator > registers an interceptor into the framework that the path of a record is > intercepted. This is much like the already accepted and implemented client > interceptors - the capability exists and it is an opt-in feature. > > As with the client interceptors and indeed interception in general, the > interceptor implementations need to be thoughtfully crafted to ensure > minimal performance impact. Yes the interceptor framework could tap into > nearly everything but would only be tapping into the subset of APIs that > the user wishes to intercept for their use case. > > Tom Aley > thomas.a...@ibm.com > > > > From: "M. Manna" <manme...@gmail.com> > To: Kafka Users <us...@kafka.apache.org> > Cc: dev@kafka.apache.org > Date: 02/12/2019 11:31 > Subject: [EXTERNAL] Re: Broker Interceptors > > > > Hi Tom, > > On Mon, 2 Dec 2019 at 09:41, Thomas Aley <thomas.a...@ibm.com> wrote: > > > Hi Kafka community, > > > > I am hoping to get some feedback and thoughts about broker interceptors. > > > > KIP-42 Added Producer and Consumer interceptors which have provided > Kafka > > users the ability to collect client side metrics and trace the path of > > individual messages end-to-end. > > > > This KIP also mentioned "Adding message interceptor on the broker makes > a > > lot of sense, and will add more detail to monitoring. However, the > > proposal is to do it later in a separate KIP". > > > > One of the motivations for leading with client interceptors was to gain > > experience and see how useable they are before tackling the server side > > implementation which would ultimately "allow us to have a more > > complete/detailed message monitoring". > > > > Broker interceptors could also provide more value than just more > complete > > and detailed monitoring such as server side schema validation, so I am > > curious to learn if anyone in the community has progressed this work; > has > > ideas about other potential server side interceptor uses or has actually > > implemented something similar. > > > > I personally feel that the cost here is the impact on performance. If I > am > right, this interceptor is going to tap into nearly everything. If you > have > strong guarantee (min.in.sync.replicas = N-1) then this may incur some > delay (and let's not forget inter broker comms protection by TLS config). > This may not be desirable for some systems. That said, it would be good to > know what others think about this. > > Thanks, > > > > > Regards, > > > > Tom Aley > > thomas.a...@ibm.com > > 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 > >
