Is "Do-It-Yourself 0.1" still useful on OpenShift Online? - openshift

Question

Currently there are two application types on OpenShift Online, which may be used for OpenShift cartridge development: Do-It-Yourself 0.1 and Cartridge Development Kit.
The description of the Cartridge Development Kit sounds much more useful:
Helps you build and deploy your own custom cartridges - the CDK hosts
your cartridge source AND allows you to easily deploy that cartridge
directly to OpenShift. For more info check out the README in the
source repository.
Is there a reason why the Do-It-Yourself 0.1 type is still available? Which one should I use for what use case?

Answer 1

From my understanding diy cartridges are for testing out frameworks on a single gear. While the CDK is to create custom cartridges to share around and enable scaling. The CDK doesn't launch the app directly but instead keeps snapshots of your git pushes so you can create apps out of it with
rhc create-app {newappname} http://{yourcdkapp}/manifest/{commit_or_tag_or_branch}
For example you could use /manifest/master to create an app out of your most recent push to the CDK
In order for a CDK to work you have to follow along this specification so that it will create the proper folder structure openshift recognizes and will execute. An important thing to note is that your app will need a control action hook, which describes other action hooks your app can execute from rhc (like start, stop, restart...). Also since it's not a diy you'll need a manifest.yml file. This is what sets up your app with ips and ports and describes what your app is to openshift.
Another thing to note: a CDK will take up a gear in order to keep. BUT If you have the CDK working you could host your code on github and use the url to that manifest.yml instead.