Migrate to operator-sdk 0.3.0

[nicolaferraro]

Fix #237
There are major changes between 0.0.7 and 0.3.x.

[lburgazzoli]

just wondering: should we create a k8sclient package with a global client and some utilities instead of passing a client instance similar to the old operator sdk?

[nicolaferraro]

Yes, now I've added a client-wrapper package that simplifies things a bit. But I'm not fully convinced on switching to the old "static var" approach...

[lburgazzoli]

what are the cons?

[nicolaferraro]

Client is injected by the controller runtime into the user controllers each time a reconciliation should be executed. Saving it to a global location and using it from there does not seem so clean to me...

Now you can assume it's always the same client, but what if it changes later (e.g. because of a periodic cache reset)?
And, in any case, you need to pass the context.Context around.. it cannot be global..

[lburgazzoli]

now it’s more clear, thx

[nicolaferraro]

Only thing missing seems to be (lupus in fabula) a cache reset in the out-of-cluster client during installation, otherwise kamel install is not able to install the CRDs as they don't exist at the beginning..