Allow virtual machines to be parameterized about kube-ansible

[leifmadsen]

Should be pretty straight forward now that feature/ipv6 is merged. Will start working on building this out as I'll need it for a development box. We don't want all our VMs to be provisioned with 24GB of RAM :)

[leifmadsen]

@dougbtv @fepan @s1061123, so I have a design question about what I want to do here.

We currently have this:

virtual_machines:                                                               
  - name: kube-master                                                           
    node_type: master                                                              
  - name: kube-node-1                                                                                                                                                                                                                          
    node_type: nodes                                                               
  - name: kube-node-2                                                              
    node_type: nodes                                                               
  - name: kube-node-3                                                              
    node_type: nodes                                                               
# - name: my-support-node                                                          
#   node_type: other                                                               
vm_parameters_ram_mb: 2048                                                         
vm_parameters_cpus: 4      

What I want to do is move the values of the vm_parameters_... to be available to the virtual_machines so that I can specify different RAM and CPU values for the machines.

I was just thinking of doing something like this:

virtual_machines:
  - name: kube-master
    node_type: master
    vm_parameters_ram_mb: 2048
    vm_parameters_cpus: 4

But then I was thinking, that maybe we'll just keep adding more and more things here... so maybe we should have a parameters dictionary?

virtual_machines:
  - name: kube-master
    node_type: master
    parameters:
        ram_mb: 2048
        cpus: 4

I'd also want to set a default, so I'd be replacing vm_parameters_... with something like:

default_parameter_ram_mb: 2048

Then if the individual dictionaries were missing, then I'd just consume the default values. Thoughts?

[dougbtv]

I, for one, really like this design. particularly the replacing the vm_parameters_* with a default_vm_parameter_* and then having the virtual_machines list of hashes with an extra param dictionary. That looks great.

The logic for weaving in the defaults doesn't come to me easily, but, it sounds fun to slang (if it's not painful, lol)

[leifmadsen]

Yea, I'm worried a bit about the default values, but I think I might know how to tackle that. We shall see! Thanks for the feedback. Going to work on this today.

[leifmadsen]

OK so I had to flatten the dictionary because of these problems:

ansible/ansible#30944 (comment)

That's why things are flat in the PR.