refactor: sizeOverride

[monrax]

This is an attempt to preserve some of the functionality of the size preset outlined in #56 -- specifically, this PR modifies the expectation of size being a way to set default values that can later be overriden, into an override itself: sizeOverride

Just like before, the following is true:

helm upgrade -i graylog ./graylog --set sizeOverride=small

deploys a cluster with the same specs as this:

helm upgrade -i graylog ./graylog --set graylog.replicas=1 --set datanode.replicas=2 --set graylog.resources.requests.cpu=2 --set graylog.resources.requests.memory=4Gi --set datanode.resources.requests.cpu=2 --set graylog.resources.requests.memory=8Gi

The difference is that now, sizeOverride in values.yaml does not establish the defaults for replicas (and eventually container requirements) for both graylog and datanode. Instead it overrides the default values that live invalues.yaml already, using a single setting instead of overriding each value individually.

Even though it keeps the same convenience/QoL feature by simplifying the number of values to set in order to achieve a given recommended configuration, this refactoring prevents any individual value override: in order to increase the graylog.replicas number, the sizeOverride="" value would need to be set first, which would unset the rest of the values like datanode.replicas and so on, which means all those values then need to be set individually. As such, this PR might be introducing more of a demo feature.

Until we sync on this issue, this PR will remain a draft.

Notes for Reviewers

• The commit history must be preserved - please use the rebase-merge or standard merge option instead of squash-merge
• Sync up with the author before merging