From 98308448d40f3c07c4afd58cf41ba2ad6dfe7e23 Mon Sep 17 00:00:00 2001
From: Christian Pointner <equinox@spreadspace.org>
Date: Sun, 29 Sep 2019 00:42:21 +0200
Subject: refactoring kubernetes roles

---
 roles/kubernetes/kubeadm/base/tasks/main.yml       |  34 +++++++
 roles/kubernetes/kubeadm/master/tasks/main.yml     | 109 +++++++++++++++++++++
 .../master/templates/kubeadm-cluster.config.j2     |  34 +++++++
 roles/kubernetes/kubeadm/node/tasks/main.yml       |  18 ++++
 roles/kubernetes/kubeadm/reset/tasks/main.yml      |   3 +
 5 files changed, 198 insertions(+)
 create mode 100644 roles/kubernetes/kubeadm/base/tasks/main.yml
 create mode 100644 roles/kubernetes/kubeadm/master/tasks/main.yml
 create mode 100644 roles/kubernetes/kubeadm/master/templates/kubeadm-cluster.config.j2
 create mode 100644 roles/kubernetes/kubeadm/node/tasks/main.yml
 create mode 100644 roles/kubernetes/kubeadm/reset/tasks/main.yml

(limited to 'roles/kubernetes/kubeadm')

diff --git a/roles/kubernetes/kubeadm/base/tasks/main.yml b/roles/kubernetes/kubeadm/base/tasks/main.yml
new file mode 100644
index 00000000..2d9b9eed
--- /dev/null
+++ b/roles/kubernetes/kubeadm/base/tasks/main.yml
@@ -0,0 +1,34 @@
+---
+- name: install kubeadm and kubectl
+  apt:
+    name:
+    - "kubeadm{% if kubernetes.pkg_version is defined %}={{ kubernetes.pkg_version }}{% endif %}"
+    - "kubectl{% if kubernetes.pkg_version is defined %}={{ kubernetes.pkg_version }}{% endif %}"
+    state: present
+
+- name: disable automatic upgrades for kubeadm and kubectl
+  when: kubernetes.pkg_version is defined
+  loop:
+  - kubeadm
+  - kubectl
+  dpkg_selections:
+    name: "{{ item }}"
+    selection: hold
+
+- name: set kubelet node-ip
+  lineinfile:
+    name: "/etc/default/kubelet"
+    regexp: '^KUBELET_EXTRA_ARGS='
+    line: 'KUBELET_EXTRA_ARGS=--node-ip={{ kubernetes.pod_ip_range | ipsubnet(kubernetes.pod_ip_range_size, kubernetes.net_index[inventory_hostname]) | ipaddr(1) | ipaddr("address") }}'
+
+- name: add kubectl/kubeadm completion for shells
+  loop:
+    - zsh
+    - bash
+  blockinfile:
+    path: "/root/.{{ item }}rc"
+    create: yes
+    marker: "### {mark} ANSIBLE MANAGED BLOCK for kubectl ###"
+    content: |
+      source <(kubectl completion {{ item }})
+      source <(kubeadm completion {{ item }})
diff --git a/roles/kubernetes/kubeadm/master/tasks/main.yml b/roles/kubernetes/kubeadm/master/tasks/main.yml
new file mode 100644
index 00000000..7cc6fe94
--- /dev/null
+++ b/roles/kubernetes/kubeadm/master/tasks/main.yml
@@ -0,0 +1,109 @@
+---
+- name: check if kubeconfig admin.conf already exists
+  stat:
+    path: /etc/kubernetes/admin.conf
+  register: kubeconfig_admin_stats
+
+### cluster not yet initialized
+
+- name: create new cluster
+  when: kubeconfig_admin_stats.stat.exists == False
+  block:
+
+  - name: generate bootstrap token for new cluster
+    command: kubeadm token generate
+    changed_when: False
+    check_mode: no
+    register: kubeadm_token_generate
+
+  - name: create kubernetes config directory
+    file:
+      path: /etc/kubernetes
+      state: directory
+
+    ## TODO test whether the generated cluster configs really works - since it has never been used...
+  - name: install cluster config for kubeadm
+    template:
+      src: kubeadm-cluster.config.j2
+      dest: /etc/kubernetes/kubeadm-cluster.config
+
+  - name: set up kubernetes master
+    command: "kubeadm init --config '/etc/kubernetes/kubeadm-cluster.config' --token '{{ kubeadm_token_generate.stdout }}' --token-ttl 42m --skip-token-print"
+    args:
+      creates: /etc/kubernetes/pki/ca.crt
+    register: kubeadm_init
+
+  - name: dump output of kubeadm init to log file
+    when: kubeadm_init.changed
+    copy:
+      content: "{{ kubeadm_init.stdout }}\n"
+      dest: /etc/kubernetes/kubeadm-init.log
+
+### cluster is already initialized
+
+- name: prepare cluster for new nodes
+  when: kubeconfig_admin_stats.stat.exists == True
+  block:
+
+  - name: fetch list of current nodes
+    command: kubectl get nodes -o name
+    changed_when: False
+    check_mode: no
+    register: kubectl_node_list
+
+  - name: save list of current nodes
+    set_fact:
+      kubernetes_current_nodes: "{{ kubectl_node_list.stdout_lines | map('replace', 'node/', '') | list }}"
+
+  - name: create bootstrap token for existing cluster
+    when: kubernetes_nodes | difference(kubernetes_current_nodes) | length > 0
+    command: kubeadm token create --ttl 42m
+    check_mode: no
+    register: kubeadm_token_create
+
+##
+
+- name: check if master is tainted (1/2)
+  command: "kubectl --kubeconfig /etc/kubernetes/admin.conf get node {{ inventory_hostname }} -o json"
+  check_mode: no
+  register: kubectl_get_node
+  changed_when: False
+
+- name: check if master is tainted (2/2)
+  set_fact:
+    kube_node_taints: "{% set node_info = kubectl_get_node.stdout | from_json %}{%if node_info.spec.taints is defined %}{{ node_info.spec.taints | map(attribute='key') | list }}{% endif %}"
+
+- name: remove taint from master node
+  when: "kubernetes.dedicated_master == False and 'node-role.kubernetes.io/master' in kube_node_taints"
+  command: kubectl --kubeconfig /etc/kubernetes/admin.conf taint nodes --all node-role.kubernetes.io/master-
+
+- name: add taint for master node
+  when: "kubernetes.dedicated_master == True and 'node-role.kubernetes.io/master' not in kube_node_taints"
+  command: "kubectl --kubeconfig /etc/kubernetes/admin.conf taint nodes {{ ansible_nodename }} node-role.kubernetes.io/master='':NoSchedule"
+
+- name: install openssl
+  apt:
+    name: openssl
+    state: present
+
+- name: get ca certificate digest
+  shell: "openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'"
+  check_mode: no
+  register: kube_ca_openssl
+  changed_when: False
+
+- name: set variables needed by kubernetes/nodes to join the cluster
+  set_fact:
+    kube_bootstrap_token: "{% if kubeadm_token_generate.stdout is defined %}{{ kubeadm_token_generate.stdout }}{% elif kubeadm_token_create.stdout is defined %}{{ kubeadm_token_create.stdout }}{% endif %}"
+    kube_bootstrap_ca_cert_hash: "sha256:{{ kube_ca_openssl.stdout }}"
+
+- name: prepare kubectl (1/2)
+  file:
+    name: /root/.kube
+    state: directory
+
+- name: prepare kubectl (2/2)
+  file:
+    dest: /root/.kube/config
+    src: /etc/kubernetes/admin.conf
+    state: link
diff --git a/roles/kubernetes/kubeadm/master/templates/kubeadm-cluster.config.j2 b/roles/kubernetes/kubeadm/master/templates/kubeadm-cluster.config.j2
new file mode 100644
index 00000000..07c4dddd
--- /dev/null
+++ b/roles/kubernetes/kubeadm/master/templates/kubeadm-cluster.config.j2
@@ -0,0 +1,34 @@
+{# https://godoc.org/k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1 #}
+apiVersion: kubeadm.k8s.io/v1beta1
+kind: ClusterConfiguration
+kubernetesVersion: v{{ kubernetes.version }}
+clusterName: {{ kubernetes.cluster_name }}
+certificatesDir: /etc/kubernetes/pki
+{% if kubernetes.api_advertise_ip %}
+controlPlaneEndpoint: "{{ kubernetes.api_advertise_ip }}:6443"
+{% endif %}
+imageRepository: k8s.gcr.io
+networking:
+  dnsDomain: cluster.local
+  podSubnet: {{ kubernetes.pod_ip_range }}
+  serviceSubnet: {{ kubernetes.service_ip_range }}
+etcd:
+  local:
+    dataDir: /var/lib/etcd
+apiServer:
+{% if kubernetes.api_extra_sans | length > 0 %}
+  certSANs:
+{%   for san in kubernetes.api_extra_sans %}
+  - {{ san }}
+{%   endfor %}
+{% endif %}
+  extraArgs:
+{% if kubernetes.api_advertise_ip %}
+    advertise-address: {{ kubernetes.api_advertise_ip }}
+{% endif %}
+    authorization-mode: Node,RBAC
+  timeoutForControlPlane: 4m0s
+controllerManager: {}
+scheduler: {}
+dns:
+  type: CoreDNS
diff --git a/roles/kubernetes/kubeadm/node/tasks/main.yml b/roles/kubernetes/kubeadm/node/tasks/main.yml
new file mode 100644
index 00000000..9f0057f9
--- /dev/null
+++ b/roles/kubernetes/kubeadm/node/tasks/main.yml
@@ -0,0 +1,18 @@
+---
+- name: get master vars
+  set_fact:
+    kube_bootstrap_token: "{{ hostvars[kubernetes_master].kube_bootstrap_token }}"
+    kube_bootstrap_ca_cert_hash: "{{ hostvars[kubernetes_master].kube_bootstrap_ca_cert_hash }}"
+    kube_master_addr: "{{ kubernetes.api_advertise_ip | default(hostvars[kubernetes_master].ansible_default_ipv4.address) }}"
+
+- name: join kubernetes node
+  command: "kubeadm join --token {{ kube_bootstrap_token }} {{ kube_master_addr }}:6443 --discovery-token-ca-cert-hash {{ kube_bootstrap_ca_cert_hash }}"
+  args:
+    creates: /etc/kubernetes/kubelet.conf
+  register: kubeadm_join
+
+- name: dump output of kubeadm join to log file
+  when: kubeadm_join.changed
+  copy:
+    content: "{{ kubeadm_join.stdout }}\n"
+    dest: /etc/kubernetes/kubeadm-join.log
diff --git a/roles/kubernetes/kubeadm/reset/tasks/main.yml b/roles/kubernetes/kubeadm/reset/tasks/main.yml
new file mode 100644
index 00000000..a6d64c7d
--- /dev/null
+++ b/roles/kubernetes/kubeadm/reset/tasks/main.yml
@@ -0,0 +1,3 @@
+---
+- name: clean up settings and files created by kubeadm
+  command: kubeadm reset -f
-- 
cgit v1.2.3