Matsuri Example

redis.rb

# Matsuri.define will generate a custom class and registers it
# Because it is a Ruby class, you can create mixins by creating a Ruby
# module and `include` it in.

# Everything is broken down into smaller `let()`. If you are not familiar
# with it, it is taken from Rspec, and defines a memoized method. We can
# then customize functionality by overriding any of the lets. In this case,
# the base class of the pod definition defines the manifests:
# https://github.com/matsuri-rb/matsuri/blob/master/lib/matsuri/kubernetes/pod.rb#L10
# Notice how I am overriding just enough to create a pod. However, I can override
# the entire `let(:spec)` to generate a completely different specification.
Matsuri.define :pod, :redis do
  let(:labels)  { { cache: 'redis' } }
  let(:volumes) { [] }

  let(:container) do
    {
      name:  'redis',
      image: 'docker.io/library/redis:3.2-alpine', # https://hub.docker.com/_/redis/
      ports: [port(6379)]
    }
  end

  # port() is just a regular (non-memoized) Ruby method. Here, it is used as
  # a helper to output the full port specification appropriate for a pod.
  # You can write your own helpers.

  # One of the helpers included in Matsuri is the ability to reference any of the
  # other specs. This is most useful with deployments, replicasets, replicationcontrollers,
  # or anything that embeds a PodSpec. This allows you to reuse the pod and instantiate
  # a pod directly (say in, dev) while still creating a deployment out of it (say in production).
end