Oh, thanks Baodi - now I understand what he meant by "calling rebuild".
I agree, it's not very intuitive.
Maybe?
client.update(ConnectionInfo.builder()
.setServiceUrl()
.set...()
.build())
On Mon, Feb 6, 2023 at 2:39 AM Baodi Shi <ba...@apache.org> wrote:
> I thought about it for a moment, and this is not a good idea.
>
> Using newBuild may be understood by the user as recreating the client
> object. It is still intuitive to add the `updateXXX` method.
>
>
> Thanks,
> Baodi Shi
>
>
> 在 2023年2月5日 23:01:57 上，Asaf Mesika <asaf.mes...@gmail.com> 写道：
>
> > Can you please write rebuild example?
> >
> > On Sun, Feb 5, 2023 at 4:05 PM Baodi Shi <ba...@apache.org> wrote:
> >
> > >
> >
> > > Not completely different IMO. When we want to update the service URL,
> >
> > >
> >
> > > we usually want to connect to another cluster. However, the cluster
> >
> > >
> >
> > > could have configured authentication, TLS for security, but we cannot
> >
> > >
> >
> > > guarantee two clusters share the same TLS certificates or
> >
> > >
> >
> > > authentication configs. I think we should group these necessary
> >
> > >
> >
> > > information into a common class like `ConnectInfo`. Then, just expose
> >
> > >
> >
> > > a method to update the `ConnectInfo` so that code could be more
> >
> > >
> >
> > > scalable.
> >
> > >
> >
> > >
> >
> > It makes sense to me.
> >
> >
> > Alternatively, can we directly support rebuilding PulsarClient?
> >
> >
> > PulsarClient client = PulsarClient.builder()
> >
> > .serviceUrl("old url")
> >
> > .tlsTrustCertsFilePath()
> >
> > .statsInterval(1, TimeUnit.SECONDS)
> >
> > .build();
> >
> >
> > client.newBuilder()
> >
> > .serviceUrl("new url")
> >
> > // tls relate
> >
> > .tlsTrustCertsFilePath()
> >
> > .statsInterval(2, TimeUnit.SECONDS)
> >
> > .build();
> >
> >
> >
> > When calling rebuild, the new configuration overwrites the old
> >
> > configuration, and if there are no settings, the old configuration is
> used.
> >
> >
> > 在 2023年2月2日 23:02:21 上，Asaf Mesika <asaf.mes...@gmail.com> 写道：
> >
> >
> > > Ok, makes sense.
> >
> > >
> >
> > >
> >
> > > On Thu, Feb 2, 2023 at 4:02 PM Yunze Xu <y...@streamnative.io.invalid>
> >
> > > wrote:
> >
> > >
> >
> > > Not completely different IMO. When we want to update the service URL,
> >
> > >
> >
> > > we usually want to connect to another cluster. However, the cluster
> >
> > >
> >
> > > could have configured authentication, TLS for security, but we cannot
> >
> > >
> >
> > > guarantee two clusters share the same TLS certificates or
> >
> > >
> >
> > > authentication configs. I think we should group these necessary
> >
> > >
> >
> > > information into a common class like `ConnectInfo`. Then, just expose
> >
> > >
> >
> > > a method to update the `ConnectInfo` so that code could be more
> >
> > >
> >
> > > scalable.
> >
> > >
> >
> > >
> >
> > > Thanks,
> >
> > >
> >
> > > Yunze
> >
> > >
> >
> > >
> >
> > > On Thu, Feb 2, 2023 at 9:39 PM Asaf Mesika <asaf.mes...@gmail.com>
> >
> > wrote:
> >
> > >
> >
> > > >
> >
> > >
> >
> > > > Ok, the last two methods IMO are a completely different topic.
> >
> > >
> >
> > > >
> >
> > >
> >
> > > > I wonder what the maintainers think about this.
> >
> > >
> >
> > > >
> >
> > >
> >
> > > > On Mon, Jan 30, 2023 at 4:16 AM Yunze Xu
> <y...@streamnative.io.invalid
> >
> > >
> >
> > >
> >
> > > > wrote:
> >
> > >
> >
> > > >
> >
> > >
> >
> > > > > In summary, the core issue is that ServiceUrlProvider could be
> >
> > >
> >
> > > > > misused. A user might want to implement its own ServiceUrlProvider
> by
> >
> > >
> >
> > > > > changing the returned value of `get` method but it actually does
> not
> >
> > >
> >
> > > > > work. The built-in implementations like AutoFailover actually work
> by
> >
> > >
> >
> > > > > these `updateXXX` methods. So it's meaningless to provide them as
> >
> > >
> >
> > > > > ServiceUrlProvider implementations.
> >
> > >
> >
> > > > >
> >
> > >
> >
> > > > > To answer your question directly: totally yes. But not only
> >
> > >
> >
> > > > > `setServiceUrl` (the name is `updateServiceUrl` in code), the
> >
> > >
> >
> > > > > `updateAuthentication` and `updateTlsTrustCertsFilePath` methods,
> >
> > >
> >
> > > > > which are not exposed to `PulsarClient`, should also be exposed.
> >
> > >
> >
> > > > >
> >
> > >
> >
> > > > > Thanks,
> >
> > >
> >
> > > > > Yunze
> >
> > >
> >
> > > > >
> >
> > >
> >
> > > > > On Sun, Jan 29, 2023 at 11:57 PM Asaf Mesika <
> asaf.mes...@gmail.com>
> >
> > >
> >
> > > > > wrote:
> >
> > >
> >
> > > > > >
> >
> > >
> >
> > > > > > Yunze - in summary - your proposal is to get rid of the
> >
> > >
> >
> > > > > ServiceUrlProvider
> >
> > >
> >
> > > > > > right? You just want to have setServiceUrl on the client instead?
> >
> > >
> >
> > > > > >
> >
> > >
> >
> > > > > >
> >
> > >
> >
> > > > > > On Wed, Jan 25, 2023 at 2:03 PM Yunze Xu
> >
> > >
> >
> > > <y...@streamnative.io.invalid>
> >
> > >
> >
> > > > > > wrote:
> >
> > >
> >
> > > > > >
> >
> > >
> >
> > > > > > > It makes sense to me. So the better way is still providing the
> >
> > >
> >
> > > > > > > `updateXXX` methods to `PulsarClient`. As for how to detect the
> >
> > >
> >
> > > > > > > connection info (e.g. service URL) changes, it's determined by
> >
> > the
> >
> > >
> >
> > > > > > > user's implementation. For example, the current
> >
> > AutoClusterFailover
> >
> > >
> >
> > > > > > > polls with a fixed interval.
> >
> > >
> >
> > > > > > >
> >
> > >
> >
> > > > > > > We can also implement a notification mechanism based on the
> >
> > >
> >
> > > > > > > `updateXXX` methods. For example, assuming we have a producer
> >
> > that
> >
> > >
> >
> > > > > > > writes the latest service URL to a topic and a consumer that
> >
> > reads
> >
> > >
> >
> > > the
> >
> > >
> >
> > > > > > > latest service URL from that topic. Then, the consumer could
> call
> >
> > >
> >
> > > > > > > `pulsarClient.updateXXX` once it receives the latest service
> URL.
> >
> > >
> >
> > > > > > >
> >
> > >
> >
> > > > > > > Thanks,
> >
> > >
> >
> > > > > > > Yunze
> >
> > >
> >
> > > > > > >
> >
> > >
> >
> > > > > > > On Tue, Jan 24, 2023 at 4:32 PM Asaf Mesika <
> >
> > asaf.mes...@gmail.com
> >
> > >
> >
> > > >
> >
> > >
> >
> > > > > wrote:
> >
> > >
> >
> > > > > > > >
> >
> > >
> >
> > > > > > > > If I understand correctly, the idea of having the ability to
> >
> > >
> >
> > > change
> >
> > >
> >
> > > > > > > > serviceUrl is to support switching over between clusters
> >
> > >
> >
> > > dynamically?
> >
> > >
> >
> > > > > > > > If that is the case, doesn't it make sense that it will
> trigger
> >
> > >
> >
> > > the
> >
> > >
> >
> > > > > > > change
> >
> > >
> >
> > > > > > > > to the client instead of the client polling it and check it
> >
> > self
> >
> > >
> >
> > > if
> >
> > >
> >
> > > > > > > > something has changed?
> >
> > >
> >
> > > > > > > >
> >
> > >
> >
> > > > > > > >
> >
> > >
> >
> > > > > > > > On Mon, Jan 23, 2023 at 5:00 AM Yunze Xu
> >
> > >
> >
> > > > > <y...@streamnative.io.invalid>
> >
> > >
> >
> > > > > > > > wrote:
> >
> > >
> >
> > > > > > > >
> >
> > >
> >
> > > > > > > > > Yes. The poll happens in the client's internal thread.
> >
> > >
> >
> > > > > > > > >
> >
> > >
> >
> > > > > > > > > Thanks,
> >
> > >
> >
> > > > > > > > > Yunze
> >
> > >
> >
> > > > > > > > >
> >
> > >
> >
> > > > > > > > > On Sun, Jan 22, 2023 at 6:56 PM Asaf Mesika <
> >
> > >
> >
> > > asaf.mes...@gmail.com
> >
> > >
> >
> > > > > >
> >
> > >
> >
> > > > > > > wrote:
> >
> > >
> >
> > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > and the client will poll the ConnectInfoProvider and
> check
> >
> > if
> >
> > >
> >
> > > > > > > something
> >
> > >
> >
> > > > > > > > > was
> >
> > >
> >
> > > > > > > > > > changed?
> >
> > >
> >
> > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > On Fri, Jan 20, 2023 at 11:19 AM Yunze Xu
> >
> > >
> >
> > > > > > > <y...@streamnative.io.invalid>
> >
> > >
> >
> > > > > > > > > > wrote:
> >
> > >
> >
> > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > I think the `updateServiceUrl` is not the initial
> >
> > >
> >
> > > purpose of
> >
> > >
> >
> > > > > > > > > exposing to
> >
> > >
> >
> > > > > > > > > > > the Client API.
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > I agree. We might need an API like
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > ```java
> >
> > >
> >
> > > > > > > > > > > ClientBuilder serviceUrlProvider(ServiceUrlProvider
> >
> > >
> >
> > > > > > > > > > > serviceUrlProvider, Duration interval)
> >
> > >
> >
> > > > > > > > > > > ```
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > But not only the service URL, as you can see, the
> >
> > >
> >
> > > > > > > > > > > `AutoClusterFailover` implementation is already beyond
> >
> > the
> >
> > >
> >
> > > > > scope of
> >
> > >
> >
> > > > > > > > > > > service URL, it uses two internal APIs
> >
> > >
> >
> > > `updateAuthentication`
> >
> > >
> >
> > > > > and
> >
> > >
> >
> > > > > > > > > > > `updateTlsTrustCertsFilePath` to update other states of
> >
> > >
> >
> > > > > > > > > > > PulsarClientImpl.
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > So from the user's perspective, they only need to
> >
> > apply
> >
> > >
> >
> > > a
> >
> > >
> >
> > > > > > > service
> >
> > >
> >
> > > > > > > > > URL
> >
> > >
> >
> > > > > > > > > > > provided to the client
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > Yes. That's when I thought of when I saw the C++ client
> >
> > >
> >
> > > catch
> >
> > >
> >
> > > > > up
> >
> > >
> >
> > > > > > > [1].
> >
> > >
> >
> > > > > > > > > > > The `initialize` and `close` methods are not necessary.
> >
> > If
> >
> > >
> >
> > > let
> >
> > >
> >
> > > > > me
> >
> > >
> >
> > > > > > > > > > > design the interface, I would like the following
> >
> > solution,
> >
> > >
> >
> > > > > which is
> >
> > >
> >
> > > > > > > > > > > more simple and can accept a lambda.
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > ```java
> >
> > >
> >
> > > > > > > > > > > public interface ServiceUrlProvider {
> >
> > >
> >
> > > > > > > > > > > String getServiceUrl();
> >
> > >
> >
> > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > ```
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > However, as I've mentioned again, now authentication
> and
> >
> > >
> >
> > > TLS
> >
> > >
> >
> > > > > info
> >
> > >
> >
> > > > > > > also
> >
> > >
> >
> > > > > > > > > > > need updates, so I have an initial design like:
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > ```java
> >
> > >
> >
> > > > > > > > > > > public class ConnectInfo {
> >
> > >
> >
> > > > > > > > > > > String serviceUrl;
> >
> > >
> >
> > > > > > > > > > > Authentication authentication;
> >
> > >
> >
> > > > > > > > > > > String tlsCertificatesFile;
> >
> > >
> >
> > > > > > > > > > > // ...
> >
> > >
> >
> > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > interface ConnectInfoProvider extends
> >
> > >
> >
> > > Supplier<ConnectInfo> {
> >
> > >
> >
> > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > ```
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > When configuring the `ConnectInfoProvider`, we should
> >
> > >
> >
> > > provide
> >
> > >
> >
> > > > > an
> >
> > >
> >
> > > > > > > > > interval.
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > And I'm going to open a PIP for it to deprecate
> >
> > >
> >
> > > > > > > `ServiceUrlProvider`.
> >
> > >
> >
> > > > > > > > > > > BTW, I found this issue when I reviewed the PR to
> migrate
> >
> > >
> >
> > > the
> >
> > >
> >
> > > > > > > > > > > ServiceUrlProvider into C++ client. IMO, the current
> >
> > >
> >
> > > design in
> >
> > >
> >
> > > > > Java
> >
> > >
> >
> > > > > > > > > > > client is bad and I don't want to adopt the same design
> >
> > in
> >
> > >
> >
> > > C++
> >
> > >
> >
> > > > > > > client.
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > Thanks,
> >
> > >
> >
> > > > > > > > > > > Yunze
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > On Thu, Jan 19, 2023 at 4:51 PM PengHui Li <
> >
> > >
> >
> > > peng...@apache.org
> >
> > >
> >
> > > > > >
> >
> > >
> >
> > > > > > > wrote:
> >
> > >
> >
> > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > Is it better to introduce a service URL detect
> interval
> >
> > >
> >
> > > to
> >
> > >
> >
> > > > > the
> >
> > >
> >
> > > > > > > > > service
> >
> > >
> >
> > > > > > > > > > > URL
> >
> > >
> >
> > > > > > > > > > > > provider?
> >
> > >
> >
> > > > > > > > > > > > I think the `updateServiceUrl` is not the initial
> >
> > >
> >
> > > purpose of
> >
> > >
> >
> > > > > > > > > exposing to
> >
> > >
> >
> > > > > > > > > > > > the Client API.
> >
> > >
> >
> > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > It looks like users just provide the interval of
> >
> > checking
> >
> > >
> >
> > > > > > > whether the
> >
> > >
> >
> > > > > > > > > > > > service URL is changed.
> >
> > >
> >
> > > > > > > > > > > > The Pulsar client will check it automatically. Using
> >
> > >
> >
> > > > > > > > > updateServiceUrl can
> >
> > >
> >
> > > > > > > > > > > > also achieve the purpose,
> >
> > >
> >
> > > > > > > > > > > > but users need to provide a fake service URL first or
> >
> > >
> >
> > > fetch
> >
> > >
> >
> > > > > the
> >
> > >
> >
> > > > > > > > > service
> >
> > >
> >
> > > > > > > > > > > URL
> >
> > >
> >
> > > > > > > > > > > > before
> >
> > >
> >
> > > > > > > > > > > > creating the client.
> >
> > >
> >
> > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > Another reason we need service URL provider API is
> that
> >
> > >
> >
> > > one
> >
> > >
> >
> > > > > team
> >
> > >
> >
> > > > > > > will
> >
> > >
> >
> > > > > > > > > > > > usually
> >
> > >
> >
> > > > > > > > > > > > provide an extra pulsar client lib with the service
> URL
> >
> > >
> >
> > > > > provider
> >
> > >
> >
> > > > > > > > > > > > implementation.
> >
> > >
> >
> > > > > > > > > > > > The lib
> >
> > >
> >
> > > > > > > > > > > > can be used across multiple teams. So from the user's
> >
> > >
> >
> > > > > > > perspective,
> >
> > >
> >
> > > > > > > > > they
> >
> > >
> >
> > > > > > > > > > > > only need to apply
> >
> > >
> >
> > > > > > > > > > > > a service URL provided to the client, they don't care
> >
> > >
> >
> > > about
> >
> > >
> >
> > > > > what
> >
> > >
> >
> > > > > > > is
> >
> > >
> >
> > > > > > > > > the
> >
> > >
> >
> > > > > > > > > > > > service URL and how to
> >
> > >
> >
> > > > > > > > > > > > update it.
> >
> > >
> >
> > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > Thanks,
> >
> > >
> >
> > > > > > > > > > > > Penghui
> >
> > >
> >
> > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > On Thu, Jan 19, 2023 at 3:43 PM Baodi Shi <
> >
> > >
> >
> > > ba...@apache.org>
> >
> > >
> >
> > > > > > > wrote:
> >
> > >
> >
> > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > Hi, Yunze:
> >
> > >
> >
> > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > Obviously, the `ServiceUrlProvider` config is
> >
> > >
> >
> > > redundant.
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > Agree. In fact, The client already provides the
> >
> > >
> >
> > > > > > > updateServiceUrl
> >
> > >
> >
> > > > > > > > > > > method,
> >
> > >
> >
> > > > > > > > > > > > > which the user can use to implement a dynamic
> update
> >
> > >
> >
> > > > > service
> >
> > >
> >
> > > > > > > URL.
> >
> > >
> >
> > > > > > > > > As
> >
> > >
> >
> > > > > > > > > > > for
> >
> > >
> >
> > > > > > > > > > > > > how the user implements it and how to close his
> >
> > >
> >
> > > resources,
> >
> > >
> >
> > > > > I
> >
> > >
> >
> > > > > > > think
> >
> > >
> >
> > > > > > > > > it
> >
> > >
> >
> > > > > > > > > > > can
> >
> > >
> >
> > > > > > > > > > > > > be left to the user.
> >
> > >
> >
> > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > 在 2023年1月19日 15:16:52 上，Yunze Xu
> >
> > >
> >
> > > > > <y...@streamnative.io.invalid
> >
> > >
> >
> > > > > > > >
> >
> > >
> >
> > > > > > > > > 写道：
> >
> > >
> >
> > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > Hi all,
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > Currently we have a `ServiceUrlProvider`
> interface
> >
> > to
> >
> > >
> >
> > > > > > > configure
> >
> > >
> >
> > > > > > > > > when
> >
> > >
> >
> > > > > > > > > > > > > > constructing a PulsarClient in
> >
> > >
> >
> > > > > > > > > `ClientBuilder#serviceUrlProvider`.
> >
> > >
> >
> > > > > > > > > > > > > > From the beginning, I thought the `getServiceUrl`
> >
> > >
> >
> > > method
> >
> > >
> >
> > > > > is
> >
> > >
> >
> > > > > > > > > called
> >
> > >
> >
> > > > > > > > > > > > > > each time the service URL is used, e.g. topic
> >
> > >
> >
> > > metadata
> >
> > >
> >
> > > > > > > lookup.
> >
> > >
> >
> > > > > > > > > > > > > > However, the `getServiceUrl` method is only
> called
> >
> > >
> >
> > > when
> >
> > >
> >
> > > > > > > > > constructing
> >
> > >
> >
> > > > > > > > > > > > > > the PulsarClient object. To update the
> >
> > PulsarClient's
> >
> > >
> >
> > > > > > > internal
> >
> > >
> >
> > > > > > > > > > > service
> >
> > >
> >
> > > > > > > > > > > > > > URL, `PulsarClient#updateServiceUrl` must be
> >
> > called.
> >
> > >
> >
> > > > > > > Therefore,
> >
> > >
> >
> > > > > > > > > if we
> >
> > >
> >
> > > > > > > > > > > > > > want to implement a `ServiceUrlProvider` that
> >
> > >
> >
> > > retrieves
> >
> > >
> >
> > > > > the
> >
> > >
> >
> > > > > > > > > latest
> >
> > >
> >
> > > > > > > > > > > > > > service URL from a database, I have to implement
> it
> >
> > >
> >
> > > like:
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > ```java
> >
> > >
> >
> > > > > > > > > > > > > > class DataBaseServiceUrlProvider implements
> >
> > >
> >
> > > > > > > ServiceUrlProvider {
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > private final ScheduledExecutorService
> executor
> >
> > =
> >
> > >
> >
> > > > > > > > > > > > > > Executors.newSingleThreadScheduledExecutor();
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > @Override
> >
> > >
> >
> > > > > > > > > > > > > > public void initialize(PulsarClient client) {
> >
> > >
> >
> > > > > > > > > > > > > > executor.schedule(() -> {
> >
> > >
> >
> > > > > > > > > > > > > > try {
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > client.updateServiceUrl(readServiceUrlFromDB()/* a
> >
> > >
> >
> > > > > > > > > > > > > > fake method */);
> >
> > >
> >
> > > > > > > > > > > > > > } catch (PulsarClientException e) {
> >
> > >
> >
> > > > > > > > > > > > > > throw new RuntimeException(e);
> >
> > >
> >
> > > > > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > > > > }, 1, TimeUnit.SECONDS);
> >
> > >
> >
> > > > > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > @Override
> >
> > >
> >
> > > > > > > > > > > > > > public String getServiceUrl() {
> >
> > >
> >
> > > > > > > > > > > > > > return "pulsar://localhost:6650";
> >
> > >
> >
> > > > > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > @Override
> >
> > >
> >
> > > > > > > > > > > > > > public void close() {
> >
> > >
> >
> > > > > > > > > > > > > > executor.shutdown();
> >
> > >
> >
> > > > > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > > > > }
> >
> > >
> >
> > > > > > > > > > > > > > ```
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > The key point is, if we didn't call
> >
> > >
> >
> > > > > > > `client.updateServiceUrl` and
> >
> > >
> >
> > > > > > > > > > > only
> >
> > >
> >
> > > > > > > > > > > > > > modified the returned value of `getServiceUrl`
> >
> > >
> >
> > > > > periodically,
> >
> > >
> >
> > > > > > > the
> >
> > >
> >
> > > > > > > > > > > > > > internal service URL would never be updated.
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > Based on the provider above, the following two
> code
> >
> > >
> >
> > > > > snippets
> >
> > >
> >
> > > > > > > > > could be
> >
> > >
> >
> > > > > > > > > > > > > > nearly the same.
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > ```java
> >
> > >
> >
> > > > > > > > > > > > > > var client =
> >
> > >
> >
> > > > > PulsarClient.builder().serviceUrlProvider(new
> >
> > >
> >
> > > > > > > > > > > > > > DataBaseServiceUrlProvider()).build();
> >
> > >
> >
> > > > > > > > > > > > > > /* ... */
> >
> > >
> >
> > > > > > > > > > > > > > client.close();
> >
> > >
> >
> > > > > > > > > > > > > > ```
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > ```java
> >
> > >
> >
> > > > > > > > > > > > > > var client =
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > >
> >
> > >
> >
> > > > >
> PulsarClient.builder().serviceUrl("pulsar://localhost:6650").build();
> >
> > >
> >
> > > > > > > > > > > > > > var provider = new DataBaseServiceUrlProvider();
> >
> > >
> >
> > > > > > > > > > > > > > provider.initialize(client);
> >
> > >
> >
> > > > > > > > > > > > > > /* ... */
> >
> > >
> >
> > > > > > > > > > > > > > provider.close();
> >
> > >
> >
> > > > > > > > > > > > > > client.close();
> >
> > >
> >
> > > > > > > > > > > > > > ```
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > Obviously, the `ServiceUrlProvider` config is
> >
> > >
> >
> > > redundant.
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > PIP-121 implements the `AutoClusterFailover` as
> the
> >
> > >
> >
> > > > > service
> >
> > >
> >
> > > > > > > URL
> >
> > >
> >
> > > > > > > > > > > > > > provider. However, it also calls the following
> >
> > >
> >
> > > methods
> >
> > >
> >
> > > > > > > > > periodically:
> >
> > >
> >
> > > > > > > > > > > > > > - PulsarClientImpl#updateAuthentication
> >
> > >
> >
> > > > > > > > > > > > > > - PulsarClientImpl#updateTlsTrustCertsFilePath
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > It's unnatural and intuitive to say a service URL
> >
> > >
> >
> > > > > provider
> >
> > >
> >
> > > > > > > could
> >
> > >
> >
> > > > > > > > > > > > > > modify the internal states of `PulsarClient`,
> >
> > >
> >
> > > including:
> >
> > >
> >
> > > > > > > > > > > > > > - the service URL
> >
> > >
> >
> > > > > > > > > > > > > > - the authentication
> >
> > >
> >
> > > > > > > > > > > > > > - the TLS trust certificate file
> >
> > >
> >
> > > > > > > > > > > > > > - ...
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > BTW, the implementation of PIP-121 [1] is
> different
> >
> > >
> >
> > > from
> >
> > >
> >
> > > > > the
> >
> > >
> >
> > > > > > > > > design
> >
> > >
> >
> > > > > > > > > > > [2].
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > [1] https://github.com/apache/pulsar/pull/13316
> >
> > >
> >
> > > > > > > > > > > > > > [2]
> https://github.com/apache/pulsar/issues/13315
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > > > Thanks,
> >
> > >
> >
> > > > > > > > > > > > > > Yunze
> >
> > >
> >
> > > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > > > >
> >
> > >
> >
> > > > > > > > > > >
> >
> > >
> >
> > > > > > > > >
> >
> > >
> >
> > > > > > >
> >
> > >
> >
> > > > >
> >
> > >
> >
> > >
> >
> > >
> >
> >
> >
>
