Hi Bobby,

thank you for a quick response. I'd rather use DRPC topology components (like DRPCSpout) and plug them into standard Topology (however I think deprecation of LinearDRPCTopologyBuider is quite misleading, so I'll create a ticket :)) .
Let me ask some questions:
- Do you know anyone used Storm DRPC in production use cases successfully?
- Do you know if there are any plans to remove support for DRPC in future Storm releases (its code looks abandoned, last commit in 2016)?
- Is there a chance that someone will document which properties can be defined in DRPCClient (currently example in Apache Storm documentation is not working, it takes 2 arguments, 3 are needed, additional one is config map).?

 It would really help to get such information, as in current state DRPC functionality looks quite unreliable to me.

Cheers,
Luk.

2018-03-08 18:13 GMT+01:00 Bobby Evans <bobby@apache.org>:
Luk,

DRPC itself is not deprecated, just the Linear DRPC builder.  In fact I would argue that we should remove that deprecation.  It was deprecated because.

"Trident subsumes the functionality provided by this class, so it's deprecated"

https://github.com/apache/storm/blob/ffa607e2464a361a8f2fa548cc8043f5a8818d04/storm-client/src/jvm/org/apache/storm/drpc/LinearDRPCTopologyBuilder.java#L53

But not everyone wants to nor can use trident for their topologies and as such it is still valid.

If you want to file a JIRA at https://issues.apache.org/jira under the STORM project to remove the deprecation and assign it to me (revans2) I would be happy to take care of that for you.

Thanks,

Bobby


On Thu, Mar 8, 2018 at 9:18 AM Łukasz Gebel <luk.gebel@gmail.com> wrote:
Hi,

DRPC functionality in Apache Storm looks deprecated, however it's still useful in some use cases.
Can anyone provide information how reliable is this functionality?

My concerns: LinearDRPCTopologyBuilder is deprecated,
documentation: http://storm.apache.org/releases/current/Distributed-RPC.html seems not to be updated (DRPC client init is outdated), there is no information which properties you should set in config (you have to dig in code) and so on.

On the other hand it is possible to use components like DRPCSpout, ReturnResult (bolt) and plug them to TopologyBuilder and their work. And these components are not deprecated.

Does anyone know if you can trust it, and if it will or won't be removed in newest versions of Storm? Did you have some unexpected problems using it?

I really appreciate any help in this matter, as it is hard to find examples of successful usages of Storm DRPC in the Internet.

Best regards,
Luk.