Module 預設值 - module defaults
前一陣子在撰寫 playbook 操作 OpenShift 時，常常模組是同一個，裏面的 kubeconfig 是固定的，寫起來就很重複。
在以前不知道有 module_defaults 的時候，都是用變數來處理。現在知道有 module_defaults 以後，就可以用這個語法來處理了。
讓我們先看看沒有用 module_defaults 之前的用法：
---
- name: OpenShift example
hosts: localhost
tasks:
- name: Create project
community.okd.k8s:
kubeconfig: "/etc/kubeconfig"
state: present
definition:
kind: Project
apiVersion: project.openshift.io/v1
metadata:
name: "Example"
annotations:
openshift.io/display-name: "Example"
spec:
finalizers:
- kubernetes
- name: Import image into image stream
community.okd.k8s:
kubeconfig: "/etc/kubeconfig"
state: present
definition:
kind: ImageStream
apiVersion: project.openshift.io/v1
metadata:
name: "hello-nginx"
namespace: "Example"
spec:
lookupPolicy:
local: false
tags:
- name: "1.0.0"
from:
kind: DockerImage
name: "quay.io/redhattraining/hello-nginx"
generation: 1
referencePolicy
type: Source
這個時候，就可以利用 module_defaults，那麼 playbook 就可以改寫為
---
- name: OpenShift example
hosts: localhost
module_defaults:
community.okd.k8s:
kubeconfig: "/etc/kubeconfig"
tasks:
- name: Create project
community.okd.k8s:
state: present
definition:
kind: Project
apiVersion: project.openshift.io/v1
metadata:
name: "Example"
annotations:
openshift.io/display-name: "Example"
spec:
finalizers:
- kubernetes
- name: Import image into image stream
community.okd.k8s:
state: present
definition:
kind: ImageStream
apiVersion: project.openshift.io/v1
metadata:
name: "hello-nginx"
namespace: "Example"
spec:
lookupPolicy:
local: false
tags:
- name: "1.0.0"
from:
kind: DockerImage
name: "quay.io/redhattraining/hello-nginx"
generation: 1
referencePolicy
type: Source
這樣就可以把共用的 kubeconfig 都寫在 module_defaults 裡，日後調整會比較容易。