Integrate DO Cloud Controller Manager

[andrewsykim]

Adds digitalocean-cloud-controller-manager as an external cloud provider.

[andrewsykim]

Default storage backend changed in Kubernetes v1.6

[andrewsykim]

Seems like this relied on the hostname being the private IP for apiserver -> kubelet communication. This is no longer required since cloud controller manager will assign proper addresses to nodes. We're also setting --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname in kube-apiserver

[ghost]

Hi @andrewsykim, I haven't been working in K8s for a while this year. Do you want to maintain this repository?

[ghost]

I'd even move this repository to its own organization

[ghost]

Done, moved repository, please follow up this issue here

#39

[5tefan]

I've been away from k8s for a while too, but looks like it's time to update again!

Hopefully can test this by the weekend. Just from initial glance at digitalocean-cloud-controller-manager, it seems to be in pretty early alpha. In that context, I'm maybe a little cautious about bringing in the dependency? @andrewsykim, you're probably in the best position to comment on the maturity of that.

This would address #21 and #38.

[andrewsykim]

@hermanjunge would love to help co-maintain this project.

@5tefan external cloud providers are definitely alpha, I would like to integrate it with this project for early adoption but I understand that there may be people relying on this project to run important workloads.

I can break up this PR, one to upgrade Kubernetes to v1.7 and the other to add the external cloud provider. After you do some testing and provide feedback we can decide what to do about the external cloud provider going forward.

[ghost]

@andrewsykim Cool. You are owner of this organization, alongside @5tefan. Thank you very much to you both for keeping this work alive.

[5tefan]

@hermanjunge Thanks for starting and sharing the project, I hope you can stick around :)

@andrewsykim Understanding this a little better from [1] and [2]. I agree and am leaning towards splitting. Would be easier to isolate any issues. Based on the roadmap in [1], I definitely support early adoption on the cloud-controller-manager. Glad to see DO supporting this! From what I understand, initial addition of the DO cloud-controller-manager should be transparent... after we've made sure of that, we could consider including here a DO LoadBalancer between the microbot pods.

[1] https://github.com/kubernetes/community/blob/master/contributors/design-proposals/cloud-provider-refactoring.md
[2] https://github.com/kubernetes/kubernetes/tree/master/pkg/cloudprovider

[bhcleek]

Just need to update the new terraform resource to use https://raw.githubusercontent.com/digitalocean/digitalocean-cloud-controller-manager/master/releases/v0.1.3.yml instead of https://raw.githubusercontent.com/digitalocean/digitalocean-cloud-controller-manager/master/releases/v0.1.0.yml`, and then this + #47 conforms to a configuration that I've successfully tested.