[jjo] add kube-router support (#3339)

* [jjo] add kube-router support

Fixes cloudnativelabs/kube-router#147.

* add kube-router as another network_plugin choice
* support most used kube-router flags via
  `kube_router_foo` vars as other plugins
* implement replacing kube-proxy (--run-service-proxy=true) via
  `kube_proxy_mode: none`, verified in a _non kubeadm_enabled_
  install, should also work for recent kubeadm releases via
  `skipKubeProxyInstall: true` config

* [jjo] address PR#3339 review from @woopstar

* add busybox image used by kube-router to downloads

* fix busybox download groups key

* rework kubeadm_enabled + kube_router_run_service_proxy

- verify it working ok w/the kubeadm_enabled and
  kube_router_run_service_proxy true or false

- introduce `kube_proxy_remove` fact, to decouple logic
  from kube_proxy_mode (which affects kubeadm configmap
  settings, thus no-good to ab-use it to 'none')

* improve kube-router.md re: kubeadm_enabled and kube_router_run_service_proxy

* address @woopstar latest review

* add inventory/sample/group_vars/k8s-cluster/k8s-net-kube-router.yml

* fix kube_router_run_service_proxy conditional for kube-proxy removal

* fix kube_proxy_remove fact (w/ |bool), add some needed kube-proxy tags on my and existing changes

* update kube-router tolerations for 1.12 compatibility

* add PriorityClass to kube-router DaemonSet

roles/download/defaults/main.yml

@@ -55,6 +55,7 @@ weave_version: "2.4.1"
 pod_infra_version: 3.1
 contiv_version: 1.2.1
 cilium_version: "v1.2.0"
+kube_router_version: "v0.2.0"
 
 # Download URLs
 kubeadm_download_url: "https://storage.googleapis.com/kubernetes-release/release/{{ kubeadm_version }}/bin/linux/{{ image_arch }}/kubeadm"
@@ -152,6 +153,8 @@ contiv_ovs_image_repo: "contiv/ovs"
 contiv_ovs_image_tag: "latest"
 cilium_image_repo: "docker.io/cilium/cilium"
 cilium_image_tag: "{{ cilium_version }}"
+kube_router_image_repo: "cloudnativelabs/kube-router"
+kube_router_image_tag: "{{ kube_router_version }}"
 nginx_image_repo: nginx
 nginx_image_tag: 1.13
 dnsmasq_version: 2.78
@@ -178,6 +181,8 @@ kubednsautoscaler_image_repo: "gcr.io/google_containers/cluster-proportional-aut
 kubednsautoscaler_image_tag: "{{ kubednsautoscaler_version }}"
 test_image_repo: busybox
 test_image_tag: latest
+busybox_image_repo: busybox
+busybox_image_tag: 1.29.2
 helm_version: "v2.9.1"
 helm_image_repo: "lachlanevenson/k8s-helm"
 helm_image_tag: "{{ helm_version }}"
@@ -391,6 +396,15 @@ downloads:
     groups:
       - k8s-cluster
 
+  kube_router:
+    enabled: "{{ kube_network_plugin == 'kube-router' }}"
+    container: true
+    repo: "{{ kube_router_image_repo }}"
+    tag: "{{ kube_router_image_tag }}"
+    sha256: "{{ kube_router_digest_checksum|default(None) }}"
+    groups:
+      - k8s-cluster
+
   pod_infra:
     enabled: true
     container: true
@@ -472,6 +486,15 @@ downloads:
     groups:
       - kube-node
 
+  busybox:
+    enabled: "{{ kube_network_plugin in ['kube-router'] }}"
+    container: true
+    repo: "{{ busybox_image_repo }}"
+    tag: "{{ busybox_image_tag }}"
+    sha256: "{{ busybox_digest_checksum|default(None) }}"
+    groups:
+      - k8s-cluster
+
   testbox:
     enabled: false
     container: true