some general cassandra4o questions

[Benjamin Schrauwen]

Dear Wille,

we are considering to use cassandra4o and have some general questions:
- I followed the installation instructions, but when running the SBT
launcher, it installs Scala 2.7.7 which does not compile the code. How
can I solve this?
- Is it possible to use cassandra4o with an embedded cassandra server?
- After a first inspection, the annotations apparently do not yet
work. When do you expect for them to be operational?
- Due to which code does cassandra4o depend on scala 2.8.0 beta?
- Is cassandra4o already used in production?

Thanks,

Benjamin.


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[Wille Faler]

Hi,
Answers inline below:

On 27 April 2010 16:37, Benjamin Schrauwen <bsch...@gmail.com> wrote:

Dear Wille,

we are considering to use cassandra4o and have some general questions:
- I followed the installation instructions, but when running the SBT
launcher, it installs Scala 2.7.7 which does not compile the code. How
can I solve this?

Are you sure that it does not compile the code? Sbt might use Scala 2.7.7 to run, but it should be able to cross-compile with 2.8, as it is set in the project/build.properties file to use:

build.scala.versions=2.8.0.Beta1

I believe this should be sufficient, but I can double check later if you are still having a problem.
 

- Is it possible to use cassandra4o with an embedded cassandra server?

Yes. The unit-tests use an embedded Cassandra server to run in fact, check EmbeddedCassandraService.scala in the src/test/scala part of the source-tree.
 

- After a first inspection, the annotations apparently do not yet
work. When do you expect for them to be operational?

That would be correct, the annotations are not yet in use.
For more trivial, "flat" mapping (String, Int, Date vars etc) it will probably be in the next week or so, as implementing it should be relatively trivial through the TypeMapper and KeySliceMapper traits.

- Due to which code does cassandra4o depend on scala 2.8.0 beta?

Cassandra4o uses default arguments (whereby a default value is assigned if none is provided by a client to a class/trait) in a number of places, a feature that is only available in 2.8.

- Is cassandra4o already used in production?

The answer to that would be "no", though I've built this with a view to use it in a larger system that is currently being implemented. So it will most likely be used in production towards the Summer.

Given the state of the code at the moment, if you can live without the Object mapping, I'd be pretty comfortable using it in production "as is" (not making any guarantees of course), as it is just provides a higher level abstraction to the default Thrift API and adds Connection pooling by extending Apache Commons Pooling (which should be relatively robust).

 

[Benjamin Schrauwen]

Dear Wille,

Thanks for the help!

> Are you sure that it does not compile the code? Sbt might use Scala 2.7.7 to run, but it should be able to cross-compile with 2.8, as it is set in the project/build.properties file to use:
> build.scala.versions=2.8.0.Beta1
>
> I believe this should be sufficient, but I can double check later if you are still having a problem.

I had to run "sbt update", and then compilation went flawless.

To get the tests passed, I had to manually edit the storage-conf and log4j setting because they have absolute paths of your machine.


I will keep an eye on the commit messages and as soon as the basic annotations work, I will give them a spin.

Cheers,

[Wille Faler]

Hi,

Running "sbt update" every once in a while is a good idea, as sbt will not update dependencies etc on it's own.

Thanks for pointing out the absolute paths on my machine, easily happens when you are the lone developer on something. I will fix it. :)