configMap

核心中用就是让配置信息和镜像文件解耦

创建configMap

命令行形式

1. 简单 KV 创建简单的KV结构配置数据

# kubectl create cm myapp-config --from-literal=nginx_port=80 --from-literal=server_name=myapp.lotusching.top

获取configMap及详细信息

# kubectl get cm myapp-config -o yaml
apiVersion: v1
data:
  nginx_port: "80"
  server_name: myapp.lotusching.top
kind: ConfigMap
metadata:
  creationTimestamp: 2018-09-12T01:59:11Z
  name: myapp-config
  namespace: default
  resourceVersion: "299594"
  selfLink: /api/v1/namespaces/default/configmaps/myapp-config
  uid: 718236fb-b62f-11e8-a27b-00163e08c384

# kubectl describe cm myapp-config
Name:         myapp-config
Namespace:    default
Labels:       <none>
Annotations:  <none>

Data
====
server_name:
----
myapp.lotusching.top
nginx_port:
----
80
Events:  <none>

Pods清单中注入configMap中的配置数据为环境变量

apiVersion: v1
kind: Pod
metadata:
  name: myapp-cm-1
  namespace: default
  labels:
    app: test
    environment: develop
spec:
  containers:
  - name: myapp
    image: ikubernetes/myapp:v1
    imagePullPolicy: IfNotPresent
    ports:
    - containerPort: 80
      name: http
      protocol: TCP
    env:
    - name: NGINX_SERVER_PORT
      valueFrom:
        configMapKeyRef:
          name: myapp-config
          key: nginx_port
    - name: NGINX_SERVER_NAME
      valueFrom:
        configMapKeyRef:
          name: myapp-config
          key: server_name

创建并检查环境变量

# kubectl apply -f first-mainitest.yaml 
pod/myapp-cm-1 created
# kubectl exec -it myapp-cm-1 "/bin/printenv"|grep NGINX
NGINX_SERVER_PORT=80
NGINX_SERVER_NAME=myapp.lotusching.top
NGINX_VERSION=1.12.2

2. 使用配置文件作为配置数据

创建包含nginx配置文件的configMap资源

# kubectl create cm nginx-www --from-file=./www.conf
configmap/nginx-www created

获取configMap信息

# kubectl get cm nginx-www -o yaml
apiVersion: v1
data:
  www.conf: |
    server {
        server_name    myapp.lotusching.top;
        listen         80;
        root           /data/web/html/;
    }
kind: ConfigMap
metadata:
  creationTimestamp: 2018-09-12T02:09:05Z
  name: nginx-www
  namespace: default
  resourceVersion: "300503"
  selfLink: /api/v1/namespaces/default/configmaps/nginx-www
  uid: d391facf-b630-11e8-a27b-00163e08c384

Pods清单中挂载configMap中的配置数据为配置文件

apiVersion: v1
kind: Pod
metadata:
  name: myapp-cm-1
  namespace: default
  labels:
    app: test
    environment: develop
spec:
  containers:
  - name: myapp
    image: ikubernetes/myapp:v1
    imagePullPolicy: IfNotPresent
    ports:
    - containerPort: 80
      name: http
      protocol: TCP
    volumeMounts:
    - name: nginxconf
      mountPath: /etc/nginx/conf.d/
      readOnly: true
  volumes:
  - name: nginxconf
    configMap:
      name: nginx-www

创建并检查配置文件

# kubectl apply -f configMap-file-demo.yaml 
pod/myapp-cm-1 created
# kubectl exec -it myapp-cm-1 /bin/sh
/ # cat /etc/nginx/conf.d/www.conf 
server {
    server_name    myapp.lotusching.top;
    listen         80;
    root           /data/web/html/;
}

可以创建下对应的解析和目录主页，不出意外然后可以成功测试访问

补充说明

• 通过注入KV配置信息为环境变量不会实时生效