Allow configuring Elasticsearch cluster name

[dnhatn]

To support multiple clusters, we need the ability to specify the cluster name when installing an Elasticsearch instance. This is not strictly required, but it prevents Elasticsearch nodes from joining the wrong cluster.

[pquentin]

Can you please look into the lint failures? They're real issues, eg. DockerProvisioner is not instantiated with cluster_name in esrally/mechanic/provisioner.py

Have you tried running the tests locally?

[dnhatn]

@pquentin I ran make test but I didn't see any failure. I will look into the lint failure. Thanks for looking.

[pquentin]

Right, this is a bit confusing. make test only runs unit tests, while make lint runs lint. make check-all will run lint, unit tests and integration tests. The mechanic module is mostly tested by integration tests, so even if they're slow if will be useful to run them.

[dnhatn]

@pquentin Great, thank you for the pointer 👍.

[dnhatn]

@pquentin It's ready for another round. Can you take another look? Thank you!

[pquentin]

Thanks!

Can you please add a test? I think we can add --cluster-name={cfg} to TestCluster.install and then at the end of TestCluster.start use the es client to get the cluster name and assert that it is cfg. This won't test all combinations but should be good enough.

[dnhatn]

@pquentin Thanks for reviews. I've addressed your comments. Would you please take another look?

[pquentin]

Thanks! There's mostly only documentation left.

[dnhatn]

@pquentin Sorry for the delay. I switched my focus to other topics recently. I have addressed your comments. Would you mind taking another look? Thank you!

[pquentin]

Thanks for iterating! LGTM.

[dnhatn]

@pquentin @inqueue Thanks for reviewing.