Thanks, Ying Zheng. Looks good overall.
One question is, should the version be specified as a Kafka version rather than
as a RPC API version? I don't think most users are aware of RPC versions, but
something like "min kafka version" would be easier to understand. That is how
we handle the minimum inter-broker protocol version and the minimum on-disk
format version, after all.
best,
Colin
On Tue, Mar 26, 2019, at 17:52, Ying Zheng wrote:
> I have rewritten the KIP. The new proposal is adding a new configuration
> min.api.version in Kafka broker.
>
> Please review the new KIP. Thank you!
>
> On Fri, Mar 1, 2019 at 11:06 AM Colin McCabe <cmcc...@apache.org> wrote:
>
> > On Wed, Feb 27, 2019, at 15:53, Harsha wrote:
> > > HI Colin,
> > > Overlooked the IDEMPOTENT_WRITE ACL. This along with
> > > client.min.version should solve the cases proposed in the KIP.
> > > Can we turn this KIP into adding min.client.version config to broker
> > > and it could be part of the dynamic config .
> >
> > +1, sounds like a good idea.
> >
> > Colin
> >
> >
> > >
> > > Thanks,
> > > Harsha
> > >
> > > On Wed, Feb 27, 2019, at 12:17 PM, Colin McCabe wrote:
> > > > On Tue, Feb 26, 2019, at 16:33, Harsha wrote:
> > > > > Hi Colin,
> > > > >
> > > > > "> I think Ismael and Gwen here bring up a good point. The version
> > of the
> > > > > > request is a technical detail that isn't really related to
> > > > > > authorization. There are a lot of other technical details like
> > this
> > > > > > like the size of the request, the protocol it came in on, etc.
> > None of
> > > > > > them are passed to the authorizer-- they all have configuration
> > knobs
> > > > > > to control how we handle them. If we add this technical detail,
> > > > > > logically we'll have to start adding all the others, and the
> > authorizer
> > > > > > API will get really bloated. It's better to keep it focused on
> > > > > > authorization, I think."
> > > > >
> > > > > probably my previous email is not clear but I am agreeing with
> > Gwen's point.
> > > > > I am not in favor of extending authorizer to support this.
> > > > >
> > > > >
> > > > > "> Another thing to consider is that if we add a new broker
> > configuration
> > > > > > that lets us set a minimum client version which is allowed, that
> > could
> > > > > > be useful to other users as well. On the other hand, most users
> > are
> > > > > > not likely to write a custom authorizer to try to take advantage
> > of
> > > > > > version information being passed to the authorizer. So, I think
> > using> a configuration is clearly the better way to go here. Perhaps it
> > can
> > > > > > be a KIP-226 dynamic configuration to make this easier to deploy?"
> > > > >
> > > > > Although minimum client version might help to a certain extent there
> > > > > are other cases where we want users to not start using transactions
> > for
> > > > > example. My proposal in the previous thread was to introduce another
> > > > > module/interface, let's say
> > > > > "SupportedAPIs" which will take in dynamic configuration to check
> > which
> > > > > APIs are allowed.
> > > > > It can throw UnsupportedException just like we are throwing
> > > > > Authorization Exception.
> > > >
> > > > Hi Harsha,
> > > >
> > > > We can already prevent people from using transactions using ACLs,
> > > > right? That's what the IDEMPOTENT_WRITE ACL was added for.
> > > >
> > > > In general, I think users should be able to think of ACLs in terms of
> > > > "what can I do" rather than "how is it implemented." For example,
> > > > maybe some day we will replace FetchRequest with GetStuffRequest. But
> > > > users who have READ permission on a topic shouldn't have to change
> > > > anything. So I think the Authorizer interface should not be aware of
> > > > individual RPC types or message versions.
> > > >
> > > > best,
> > > > Colin
> > > >
> > > >
> > > > >
> > > > >
> > > > > Thanks,
> > > > > Harsha
> > > > >
> > > > >
> > > > > n Tue, Feb 26, 2019, at 10:04 AM, Colin McCabe wrote:
> > > > > > Hi Harsha,
> > > > > >
> > > > > > I think Ismael and Gwen here bring up a good point. The version
> > of the
> > > > > > request is a technical detail that isn't really related to
> > > > > > authorization. There are a lot of other technical details like
> > this
> > > > > > like the size of the request, the protocol it came in on, etc.
> > None of
> > > > > > them are passed to the authorizer-- they all have configuration
> > knobs
> > > > > > to control how we handle them. If we add this technical detail,
> > > > > > logically we'll have to start adding all the others, and the
> > authorizer
> > > > > > API will get really bloated. It's better to keep it focused on
> > > > > > authorization, I think.
> > > > > >
> > > > > > Another thing to consider is that if we add a new broker
> > configuration
> > > > > > that lets us set a minimum client version which is allowed, that
> > could
> > > > > > be useful to other users as well. On the other hand, most users
> > are
> > > > > > not likely to write a custom authorizer to try to take advantage
> > of
> > > > > > version information being passed to the authorizer. So, I think
> > using
> > > > > > a configuration is clearly the better way to go here. Perhaps it
> > can
> > > > > > be a KIP-226 dynamic configuration to make this easier to deploy?
> > > > > >
> > > > > > cheers,
> > > > > > Colin
> > > > > >
> > > > > >
> > > > > > On Mon, Feb 25, 2019, at 15:43, Harsha wrote:
> > > > > > > Hi Ying,
> > > > > > > I think the question is can we add a module in the core
> > which
> > > > > > > can take up the dynamic config and does a block certain APIs.
> > This
> > > > > > > module will be called in each of the APIs like the authorizer
> > does
> > > > > > > today to check if the API is supported for the client.
> > > > > > > Instead of throwing AuthorizationException like the authorizer
> > does
> > > > > > > today it can throw UnsupportedException.
> > > > > > > Benefits are, we are keeping the authorizer interface as is and
> > adding
> > > > > > > the flexibility based on dynamic configs without the need for
> > > > > > > categorizing broker APIs and it will be easy to extend to do
> > additional
> > > > > > > options, like turning off certain features which might be in
> > interest
> > > > > > > to the service providers.
> > > > > > > One drawback, It will introduce another call to check instead
> > of
> > > > > > > centralizing everything around Authorizer.
> > > > > > >
> > > > > > > Thanks,
> > > > > > > Harsha
> > > > > > >
> > > > > > > On Mon, Feb 25, 2019, at 2:43 PM, Ying Zheng wrote:
> > > > > > > > If you guys don't like the extension of authorizer interface,
> > I will just
> > > > > > > > propose a single broker dynamic configuration:
> > client.min.api.version, to
> > > > > > > > keep things simple.
> > > > > > > >
> > > > > > > > What do you think?
> > > > > > > >
> > > > > > > > On Mon, Feb 25, 2019 at 2:23 PM Ying Zheng <yi...@uber.com>
> > wrote:
> > > > > > > >
> > > > > > > > > @Viktor Somogyi-Vass, @Harsha, It seems the biggest concern
> > is the
> > > > > > > > > backward-compatibility to the existing authorizers. We can
> > put the new
> > > > > > > > > method into a new trait / interface:
> > > > > > > > > trait AuthorizerEx extends Authorizer {
> > > > > > > > > def authorize(session: Session, operation: Operation,
> > resource: Resource,
> > > > > > > > > apiVersion: Short): Boolean
> > > > > > > > > }
> > > > > > > > >
> > > > > > > > > When loading an authorizer class, broker will check if the
> > class
> > > > > > > > > implemented AuthorizerEx interface. If not, broker will
> > wrapper the
> > > > > > > > > Authorizer object with an Adapter class, in which
> > authorizer(...
> > > > > > > > > apiVersion) call is translated to the old authorizer() call.
> > So that, both
> > > > > > > > > old and new Authorizer is supported and can be treated as
> > AuthorizerEx in
> > > > > > > > > the new broker code.
> > > > > > > > >
> > > > > > > > > As for the broker dynamic configuration approach, I'm not
> > sure how to
> > > > > > > > > correctly categorize the 40+ broker APIs into a few
> > categories.
> > > > > > > > > For example, describe is used by producer, consumer, and
> > admin. Should it
> > > > > > > > > be controlled by producer.min.api.version or
> > consumer.min.api.version?
> > > > > > > > > Should producer.min.api.version apply to transaction
> > operations?
> > > > > > > > >
> > > > > > > > >
> > > > > > > > > On Mon, Feb 25, 2019 at 10:33 AM Harsha <ka...@harsha.io>
> > wrote:
> > > > > > > > >
> > > > > > > > >> I think the motivation of the KIP is to configure which API
> > we want to
> > > > > > > > >> allow for a broker.
> > > > > > > > >> This is challenging for a hosted service where you have
> > customers with
> > > > > > > > >> different versions of clients.
> > > > > > > > >> It's not just about down conversion but for example
> > transactions, there
> > > > > > > > >> is a case where we do not want to allow users to start
> > using transactions
> > > > > > > > >> and there is no way to disable to this right now and as
> > specified in the
> > > > > > > > >> KIP, having a lock on which client versions we support.
> > > > > > > > >> Authorizer's original purpose is to allow policies to be
> > enforced for
> > > > > > > > >> each of the Kafka APIs, specifically in the context of
> > security.
> > > > > > > > >> Extending this to a general purpose gatekeeper might not be
> > suitable and
> > > > > > > > >> as mentioned in the thread every implementation of
> > authorizer needs to
> > > > > > > > >> re-implement to provide the same set of functionality.
> > > > > > > > >> I think it's better to add an implementation which will use
> > a broker's
> > > > > > > > >> dynamic config as mentioned in approach 1.
> > > > > > > > >>
> > > > > > > > >> Thanks,
> > > > > > > > >> Harsha
> > > > > > > > >>
> > > > > > > > >> On Sat, Feb 23, 2019, at 6:21 AM, Ismael Juma wrote:
> > > > > > > > >> > Thanks for the KIP. Have we considered the existing topic
> > config that
> > > > > > > > >> makes
> > > > > > > > >> > it possible to disallow down conversions? That's the
> > biggest downside in
> > > > > > > > >> > allowing older clients.
> > > > > > > > >> >
> > > > > > > > >> > Ismael
> > > > > > > > >> >
> > > > > > > > >> > On Fri, Feb 22, 2019, 2:11 PM Ying Zheng
> > <yi...@uber.com.invalid>
> > > > > > > > >> wrote:
> > > > > > > > >> >
> > > > > > > > >> > >
> > > > > > > > >> > >
> > > > > > > > >> >
> > > > > > > > >>
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>
