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Kafka >> mail # dev >> guide to contributing kafka clients

Jay Kreps 2011-11-29, 07:51
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Re: guide to contributing kafka clients
For the testing purposes it would be extremely useful to have a generic set
of packets defined to unit test what a client must be able generate and
receive.  Then each client can be certified by testing against a known set
of expectations for the packet parsing & generation rather than having to
bring up a broker for unit tests.  Then as you suggest, some kind of
integration suite would be useful as well, if the broker could run in some
kind of test mode..
On Tue, Nov 29, 2011 at 2:51 AM, Jay Kreps <[EMAIL PROTECTED]> wrote:

> Dave wrote an excellent guide to implementing a kafka client here:
> http://readthedocs.org/docs/brod/en/latest/spec.html <[EMAIL PROTECTED]>
> One point that was raised in the discussion was that we don't currently
> have a lot of standardization or documentation for clients. For example
> there is no documentation on the site, inconsistent or no examples in the
> source, and inconsistent or no integration tests for the clients. Overall
> our approach to clients has been to be somewhat liberal in what we except
> on the assumption that something is better than nothing. Unfortunately the
> clients are somewhat harmed by lack of a clear model to follow.
> I was thinking it might be good to have a standard for these and try to
> move the clients towards these standards and only take new clients that
> meet the standards. Here is what I was thinking should be a minimum for us
> to take a client:
>   - A patch for documentation
>   http://svn.apache.org/repos/asf/incubator/kafka/site that adds
>   quickstart style instructions for usage. We should make the existing
>   quickstart link a list with an entry for each language.
>   - An integration test suite which can be run against a running broker/zk
>   on the default port and localhost. Not sure of the best format for these,
>   but maybe just a shell script that can be invoked by doing
>   clients/<lang>/test.sh (the tests themselves can be in the client
> language,
>   this just gives a uniform way to run them as part of a regression suite).
>   This script should exit with a non-zero code if one or more tests fail
> and
>   print diagnostic information.
>   - An entry in the examples examples/src/main/<lang> directory which
>   gives complete code for a working example.
>   - An owner for this client who would be willing to maintain this code
>   going forward. This probably isn't a hugely time consuming job, but it is
>   good to have a contact person who can be point for questions or fixes.
>   - A self-assessment of the "production readiness" of the client. I think
>   it is fine to take proof-of-concept code since it gives people something
> to
>   work from, but it is good to be able to give people some assessment of
> how
>   production-ready it is so people don't run into problems and have a
>   negative reaction to the project as a whole.
> Any other criteria we should add?
> -Jay
Jeffrey Damick 2011-11-29, 15:36
Taylor Gautier 2011-11-29, 15:42
David Ormsbee 2011-11-29, 18:27
Jay Kreps 2011-11-29, 18:42