Kubernetes 实战教学，手把手教您如何在 K8s 平台上使用 Compose（二）

野性酷女 2022-02-13 02:53 144阅读 0赞

![screenshot][]

出品丨Docker公司（ID：docker-cn）  
编译丨小东  
每周一、三、五，与您不见不散！

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用过 Kubernetes 的用户都知道 Kubernetes API 真的非常庞大。在最新的版本中，从 Pods 和 Deployments 到 Validating Webhook Configuration 和 ResourceQuota，超过 50 个一级对象。如果您是开发人员，我确信这会很容易导致群集配置时出现紊乱。因此，需要一种简化的方法（如 Swarm CLI / API）来部署和管理在 Kubernetes 集群上运行的应用程序。在上一篇文章[《Kubernetes 实战教学，手把手教您如何在 K8s 平台上使用 Compose（一）》][Kubernetes _ K8s _ Compose]中，简要的介绍了简化 Kubernetes 部署以及管理的工具 —— Compose，今天将展示如何在 Kubernetes 上运用 Compose 的实战演示。

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### 测试所用的基础设施 ###

*  Docker 版本：Docker Desktop Community v2.0.1.0；
 *  系统：macOS High Sierra v10.13.6；
 *  Docker Engine：v18.09.1；
 *  Docker Compose：v1.23.2；
 *  Kubernetes：v1.13.0；

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### 先决条件 ###

*  浏览 [https://download.docker.com/mac/edge/30090/Docker.dmg][https_download.docker.com_mac_edge_30090_Docker.dmg]，下载并安装 Docker Desktop Community Edition v2.0.1.0；
 *  按下图所示的功能启用 Kubernetes；  
    
    
    ![screenshot][screenshot 1]

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### 验证 Docker Desktop 版本 ###

[Captains-Bay]? > docker version
    
    Client: Docker Engine - Community
    
     Version:          18.09.1
    
     API version:      1.39
    
     Go version:       go1.10.6
    
     Git commit:       4c52b90
    
     Built:            Wed Jan 9 19:33:12 2019
    
     OS/Arch:          darwin/amd64
    
     Experimental:     false
    
     
    
    Server: Docker Engine - Community
    
     Engine:
    
     Version:         18.09.1
    
     API version:     1.39 (minimum version 1.12)
    
     Go version:      go1.10.6
    
     Git commit:      4c52b90
    
     Built:           Wed Jan 9 19:41:49 2019
    
     OS/Arch:         linux/amd64
    
     Experimental:    true
    
     Kubernetes:
    
     Version:         v1.12.4
    
     StackAPI:        v1beta2
    
    [Captains-Bay]? >

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### 安装 Minikube ###

curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-darwin-amd64 \
     && chmod +x minikube

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### 验证 Minikube 版本 ###

minikube version
    minikube version: v0.32.0

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### 检查 Minikube 状态 ###

minikube status
    host: Stopped
    kubelet:
    apiserver:

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### 开始 Minikube ###

![screenshot][screenshot 2]

]? > minikube start
    Starting local Kubernetes v1.12.4 cluster...
    Starting VM...
    Getting VM IP address...
    Moving files into cluster...
    Setting up certs...
    Connecting to cluster...
    Setting up kubeconfig...
    Stopping extra container runtimes...
    Machine exists, restarting cluster components...
    Verifying kubelet health ...
    Verifying apiserver health ....Kubectl is now configured to use the cluster.
    Loading cached images from config file.
     
    Everything looks great. Please enjoy minikube!
     
    By now, you should be able to see context switching happening under UI windows under Kubernetes section as shown below:

### 检查 Minikube 状态 ###

? > minikube status
    
    host: Running
    
    kubelet: Running
    
    apiserver: Running
    
    kubectl: Correctly Configured: pointing to minikube-vm at 192.168.99.100[Captains-Bay]? >

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### 列出 Minikube 集群节点 ###

kubectl get nodes
    NAME      STATUS   ROLES    AGE      VERSION
    minikube  Ready    master   12h      v1.12.4

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### 创建“compose”命名空间 ###

kubectl create namespace compose
    namespace "compose" created

### 创建“tiller”服务帐户 ###

kubectl -n kube-system create serviceaccount tiller
    
    serviceaccount "tiller" created

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### 授予对集群的访问权限 ###

kubectl -n kube-system create clusterrolebinding tiller --clusterrole cluster-admin --serviceaccount kube-system:tiller
    clusterrolebinding "tiller" created

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### 初始化 Helm 组件 ###

? > helm init --service-account tiller
    
    $HELM_HOME has been configured at /Users/ajeetraina/.helm.
    
     
    
    Tiller (the Helm server-side component) has been installed into your Kubernetes Cluster.
    
     
    
    Please note: by default, Tiller is deployed with an insecure 'allow unauthenticated users' policy.
    
    For more information on securing your installation see: https://docs.helm.sh/using_helm/#securing-your-helm-installation
    
    Happy Helming!

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### 验证 Helm 版本 ###

helm version
    Client: &version.Version{SemVer:"v2.12.1", GitCommit:"20adb27c7c5868466912eebdf6664e7390ebe710", GitTreeState:"clean"}
    Server: &version.Version{SemVer:"v2.12.1", GitCommit:"20adb27c7c5868466912eebdf6664e7390ebe710", GitTreeState:"clean"}

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### 部署 etcd operator ###

? > helm install --name etcd-operator stable/etcd-operator --namespace compose
    NAME:  etcd-operator
    LAST DEPLOYED: Fri Jan 11 10:08:06 2019
    NAMESPACE: compose
    STATUS: DEPLOYED
     
    RESOURCES:
    ==> v1/ServiceAccount
    NAME                                              SECRETS AGE
    etcd-operator-etcd-operator-etcd-backup-operator  1       1s
    etcd-operator-etcd-operator-etcd-operator         1       1s
    etcd-operator-etcd-operator-etcd-restore-operator 1       1s
     
    ==> v1beta1/ClusterRole
    NAME                                      AGE
    etcd-operator-etcd-operator-etcd-operator 1s
     
    ==> v1beta1/ClusterRoleBinding
    NAME                                              AGE
    etcd-operator-etcd-operator-etcd-backup-operator  1s
    etcd-operator-etcd-operator-etcd-operator         1s
    etcd-operator-etcd-operator-etcd-restore-operator 1s
     
    ==> v1/Service
    NAME                  TYPE      CLUSTER-IP     EXTERNAL-IP PORT(S)   AGE
    etcd-restore-operator ClusterIP 10.104.102.245       19999/TCP 1s
     
    ==> v1beta1/Deployment
    NAME                                              DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
    etcd-operator-etcd-operator-etcd-backup-operator  1       1       1          0         1s
    etcd-operator-etcd-operator-etcd-operator         1       1       1          0         1s
    etcd-operator-etcd-operator-etcd-restore-operator 1       1       1          0         1s
     
    ==> v1/Pod(related)
    NAME                                                            READY STATUS            RESTARTS AGE
    etcd-operator-etcd-operator-etcd-backup-operator-7978f8bc4r97s7 0/1   ContainerCreating 0        1s
    etcd-operator-etcd-operator-etcd-operator-6c57fff9d5-kdd7d      0/1   ContainerCreating 0        1s
    etcd-operator-etcd-operator-etcd-restore-operator-6d787599vg4rb 0/1   ContainerCreating 0        1s
     
    NOTES:
    1. etcd-operator deployed.
     If you would like to deploy an etcd-cluster set cluster.enabled to true in values.yaml
     Check the etcd-operator logs
       export POD=$(kubectl get pods -l app=etcd-operator-etcd-operator-etcd-operator --namespace compose --output name)
       kubectl logs $POD --namespace=compose
    ? >

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### 创建 etcd 集群 ###

$cat compose-etcd.yaml
    apiVersion: "etcd.database.coreos.com/v1beta2"
    kind: "EtcdCluster"
    metadata:
     name: "compose-etcd"
     namespace: "compose"
    spec:
     size: 3
     version: "3.2.13"
    kubectl apply -f compose-etcd.yaml
    etcdcluster "compose-etcd" created

这将在 compose 命名空间中引入一个 etcd 集群。

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### 下载 Compose 安装程序 ###

wget https://github.com/docker/compose-on-kubernetes/releases/download/v0.4.18/installer-darwin

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### 在 Kubernetes 上部署 Compose ###

./installer-darwin -namespace=compose -etcd-servers=http://compose-etcd-client:2379 -tag=v0.4.18
    INFO[0000] Checking installation state
    INFO[0000] Install image with tag "v0.4.18" in namespace "compose"
    INFO[0000] Api server: image: "docker/kube-compose-api-server:v0.4.18", pullPolicy: "Always"
    INFO[0000] Controller: image: "docker/kube-compose-controller:v0.4.18", pullPolicy: "Always"

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### 确保已启用 Compose Stack 控制器 ###

[Captains-Bay]? > kubectl api-versions| grep compose
    compose.docker.com/v1beta1
    compose.docker.com/v1beta2

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### 列出 Minikube 的服务 ###

[Captains-Bay]? > minikube service list
    
    |-------------|-------------------------------------|-----------------------------|
    
    | NAMESPACE |               NAME                |            URL            |
    
    |-------------|-------------------------------------|-----------------------------|
    
    | compose    | compose-api                        | No node port               |
    
    | compose    | compose-etcd-client                | No node port                             |
    
    | compose    | etcd-restore-operator              | No node port               |
    
    | default    | db1                                | No node port               |
    
    | default    | example-etcd-cluster-client-service | http://192.168.99.100:32379 |
    
    | default    | kubernetes                         | No node port               |
    
    | default    | web1                               | No node port               |
    
    | default    | web1-published                     | http://192.168.99.100:32511 |
    
    | kube-system | kube-dns                           | No node port               |
    
    | kube-system | kubernetes-dashboard               | No node port               |
    
    | kube-system | tiller-deploy                      | No node port               |
    
    |-------------|-------------------------------------|-----------------------------|
    
    [Captains-Bay]? >

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### 验证 StackAPI ###

直接使用 Docker Compose 部署 Web 应用程序堆栈

[Captains-Bay]? > docker stack deploy -c docker-compose2.yml myapp4
    
    Waiting for the stack to be stable and running...
    
    db1: Ready         [pod status: 1/2 ready, 1/2 pending, 0/2 failed]
    
    web1: Ready       [pod status: 2/2 ready, 0/2 pending, 0/2 failed]
    
     
    
    Stack myapp4 is stable and running
    
     
    
    [Captains-Bay]? > docker stack ls
    
    NAME               SERVICES           ORCHESTRATOR       NAMESPACE
    
    myapp4             2                  Kubernetes         default
    
    [Captains-Bay]? > kubectl get po
    
    NAME                   READY    STATUS   RESTARTS  AGE
    
    db1-55959c855d-jwh69   1/1      Running  0         57s
    
    db1-55959c855d-kbcm4   1/1      Running  0         57s
    
    web1-58cc9c58c7-sgsld  1/1      Running  0         57s
    
    web1-58cc9c58c7-tvlhc  1/1      Running  0         57s

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因此，我们使用 Docker Compose 文件成功地将一个 Web 应用程序栈部署到运行在 Minikube 中的单节点 Kubernetes 集群上。

[screenshot]: /images/20220213/ff7ca785b9ae4cff9f346a922ee5bed1.png
[Kubernetes _ K8s _ Compose]: https://yq.aliyun.com/articles/690385?spm=a2c4e.11155435.0.0.12fb3312pdA6oL
[https_download.docker.com_mac_edge_30090_Docker.dmg]: https://download.docker.com/mac/edge/30090/Docker.dmg
[screenshot 1]: /images/20220213/8e2e38687eb94fb7b052df6c0fb84040.png
[screenshot 2]: /images/20220213/0c17ae8953724a548dbd50d874f757fd.png