在 Kubernetes 上使用 Tekton 快速实现应用自动发布

Tekton 是一个功能强大的 Kubernetes 原生开源框架，用于建立持续集成和交付系统。java

经过抽象底层实现细节，用户能够跨多云平台和本地系统进行构建、测试和部署。git

Tekton 提供的开源组件能够跨供应商，Tekton 提供的管道、版本、工做流程和其余 CI/CD 组件的行业规范一致，能够和你现有的 CI/CD 工具（例如：Jenkins、Jenkins X、Skaffold 和 Knative 等）配合使用。github

Tekton 和其它几种 CI/CD 工具的比较。web

使用 Tekton 的内置最佳实践能够快速建立云原生 CI / CD 管道，目标是让开发人员建立和部署不可变镜像，管理基础架构的版本控制或执行更简单的回滚。还能够利用 Tekton 的滚动部署，蓝 / 绿部署，金丝雀部署或 GitOps 工做流等高级部署模式。docker

使用 Tekton 可跨多个环境（例如：VM、无服务器、Kubernetes 或 Firebase）进行构建，测试和部署。你还能够使用 Tekton 管道跨多云平台或混合环境进行部署。apache

Tekton 提供了最大的灵活性，让你能够使用本身喜欢的 CI/CD 工具构建强大的管道。api

官方项目地址：https://github.com/tektoncd/pipelinetomcat

下面来看一个基于阿里云 Kubernetes 服务部署 Tekton Pipeline 的实例，部署完成后咱们使用它来完成源码拉取、应用打包、镜像推送和应用部署。

服务器

Tekton Pipeline 中有 5 类对象，核心理念是经过定义 YAML 定义构建过程，构建任务的状态存放在 status 字段中。微信

其中 5 类对象分别是：PipelineResouce、Task、TaskRun、Pipeline、PipelineRun。

Task 是单个任务的构建过程，须要经过定义 TaskRun 任务去运行 Task。

Pipeline 包含多个 Task，并在此基础上定义 input 和 output，input 和 output 以 PipelineResource 做为交付。

PipelineResource 是可用于 input 和 output 的对象集合。

一样地,须要定义 PipelineRun 才会运行 Pipeline。

在阿里云 Kubernetes 集群中部署 Tekton Pipeline

$ kubectl apply --filename https://storage.googleapis.com/tekton-releases/latest/release.yaml

查看Tekton Pipelines组件是否运行正常：

$ kubectl -n tekton-pipelines get poNAME READY STATUS RESTARTS AGEtekton-pipelines-controller-6bcd7ff5d6-vzmrh 1/1 Running 0 25htekton-pipelines-webhook-6856cf9c47-l6nj6 1/1 Running 0 25h

建立 Git Resource 和 Registry Resource

编辑 git-pipeline-resource.yaml 文件

# git repo 的分支名称为 tektonapiVersion: tekton.dev/v1alpha1kind: PipelineResourcemetadata: name: git-pipeline-resourcespec: type: git params: - name: revision value: tekton - name: url value: https://code.aliyun.com/haoshuwei/jenkins-demo.git

编辑 registry-pipeline-resource.yaml 文件

# 容器镜像仓库地址为 registry.cn-hangzhou.aliyuncs.com/haoshuwei/tekton-demo， 标签为 latestapiVersion: tekton.dev/v1alpha1kind: PipelineResourcemetadata: name: registry-pipeline-resourcespec: type: image params: - name: url value: registry.cn-hangzhou.aliyuncs.com/haoshuwei/tekton-demo

建立 pipeline resource

$ kubectl -n tekton-pipelines create -f git-pipeline-resource.yaml$ kubectl -n tekton-pipelines create -f registry-pipeline-resource.yaml

查看已建立的 pipeline resource 资源

$ kubectl -n tekton-pipelines get PipelineResourceNAME AGEgit-pipeline-resource 2hregistry-pipeline-resource 2h

建立 Git Repo / Docker Registry Authentication

拉取私有 Git 源码项目须要配置使用 Git Repo Authentication，拉取和推送 Docker 镜像须要配置 Docker Registry Authentication。

在 Tekton Pipeline 中，Git Repo / Docker Registry Authentication 会被定义成ServiceAccount来使用。

编辑 secret tekton-basic-user-pass-git.yaml

apiVersion: v1kind: Secretmetadata: name: tekton-basic-user-pass-git annotations: tekton.dev/git-0: https://code.aliyun.comtype: kubernetes.io/basic-authstringData: username: <cleartext non-encoded> password: <cleartext non-encoded>

编辑 secret tekton-basic-user-pass-registry.yaml

apiVersion: v1kind: Secretmetadata: name: tekton-basic-user-pass-registry annotations: tekton.dev/docker-0: https://registry.cn-hangzhou.aliyuncs.comtype: kubernetes.io/basic-authstringData: username: <cleartext non-encoded> password: <cleartext non-encoded>

编辑 serviceaccount tekton-git-and-registry.yaml

apiVersion: v1kind: ServiceAccountmetadata: name: tekton-git-and-registrysecrets: - name: tekton-basic-user-pass-git - name: tekton-basic-user-pass-registry

建立 serviceaccount

$ kubectl -n tekton-pipelines create -f tekton-basic-user-pass-git.yaml$ kubectl -n tekton-pipelines create -f tekton-basic-user-pass-registry.yaml$ kubectl -n tekton-pipelines create -f tekton-git-and-registry.yaml

查看 secret 以及 sa

$ kubectl -n tekton-pipelines get secretNAME TYPE DATA AGEdefault-token-pwncj kubernetes.io/service-account-token 3 25htekton-basic-user-pass-git kubernetes.io/basic-auth 2 151mtekton-basic-user-pass-registry kubernetes.io/basic-auth 2 151mtekton-git-and-registry-token-tr95m kubernetes.io/service-account-token 3 151mtekton-pipelines-controller-token-lc2fv kubernetes.io/service-account-token 3 25h webhook-certs Opaque 3 25h
$ kubectl -n tekton-pipelines get saNAME SECRETS AGEdefault 1 25htekton-git-and-registry 3 152mtekton-pipelines-controller 1 25h

配置 serviceaccount

配置一个 tekton-git-and-registry 账号以获取命名空间 tekton-pipelines 的管理权限，用于部署应用。

建立 ClusterRoleBinding tekton-cluster-admin

apiVersion: rbac.authorization.k8s.io/v1kind: ClusterRoleBindingmetadata: name: tekton-cluster-adminsubjects: - kind: ServiceAccount name: tekton-git-and-registry namespace: tekton-pipelinesroleRef: kind: ClusterRole name: cluster-admin apiGroup: rbac.authorization.k8s.io

建立一个 Task

建立 task build-app.yaml

apiVersion: tekton.dev/v1alpha1kind: Taskmetadata: name: build-appspec: inputs: resources: - name: java-demo type: git params: - name: pathToDockerFile description: The path to the dockerfile to build default: /workspace/java-demo/Dockerfile - name: pathToContext description: The build context used by Kaniko default: /workspace/java-dem - name: pathToYaml description: The path to teh manifest to apply outputs: resources: - name: builtImage type: image steps: - name: build-mvn-package image: registry.cn-beijing.aliyuncs.com/acs-sample/jenkins-slave-maven:3.3.9-jdk-8-alpine workingDir: /workspace/java-demo command: - mvn args: - package - -B - -DskipTests - name: build-docker-image image: registry.cn-beijing.aliyuncs.com/acs-sample/jenkins-slave-kaniko:0.6.0 command: - kaniko args: - --dockerfile=${inputs.params.pathToDockerFile} - --destination=${outputs.resources.builtImage.url} - --context=${inputs.params.pathToContext} - name: deploy-app image: registry.cn-beijing.aliyuncs.com/acs-sample/jenkins-slave-kubectl:1.11.5 command: - kubectl args: - apply - -f - ${inputs.params.pathToYaml}

建立 TaskRun 运行任务

建立 taskrun build-app-task-run.yaml

apiVersion: tekton.dev/v1alpha1kind: TaskRunmetadata: name: build-app-task-runspec: serviceAccount: tekton-git-and-registry taskRef: name: build-app trigger: type: manual inputs: resources: - name: java-demo resourceRef: name: git-pipeline-resource params: - name: pathToDockerFile value: Dockerfile - name: pathToContext value: /workspace/java-demo - name: pathToYaml value: /workspace/java-demo/deployment.yaml outputs: resources: - name: builtImage resourceRef: name: registry-pipeline-resource

查看构建状态以及日志

查看 taskrun 状态

$ kubectl -n tekton-pipelines get taskrunNAME SUCCEEDED REASON STARTTIME COMPLETIONTIMEbuild-app-task-run Unknown Pending 4s

查看构建日志

$ kubectl -n tekton-pipelines get poNAME READY STATUS RESTARTS AGEbuild-app-task-run-pod-b8f890 3/5 Running 0 75stekton-pipelines-controller-6bcd7ff5d6-vzmrh 1/1 Running 0 25htekton-pipelines-webhook-6856cf9c47-l6nj6 1/1 Running 0 25h
$ kubectl -n tekton-pipelines logs -f build-app-task-run-pod-b8f890Error from server (BadRequest): a container name must be specified for pod build-app-task-run-pod-b8f890, choose one of: [build-step-git-source-git-pipeline-resource-77l5v build-step-build-mvn-package build-step-build-docker-image build-step-deploy-app nop] or one of the init containers: [build-step-credential-initializer-8dsnm build-step-place-tools]

MVN Build 的日志

$ kubectl -n tekton-pipelines logs -f build-app-task-run-pod-b8f890 -c build-step-build-mvn-package[INFO] Scanning for projects...[INFO][INFO] ------------------------------------------------------------------------[INFO] Building jenkins-demo-web 1.0.0-SNAPSHOT[INFO] ------------------------------------------------------------------------[INFO] Downloading: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/maven-resources-plugin-2.6.pom[INFO] Downloaded: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/maven-resources-plugin-2.6.pom (8 KB at 7.3 KB/sec)[INFO] Downloading: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-plugins/23/maven-plugins-23.pom[INFO] Downloaded: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-plugins/23/maven-plugins-23.pom (9 KB at 26.7 KB/sec)[INFO] Downloading: https://repo.maven.apache.org/maven2/org/apache/maven/maven-parent/22/maven-parent-22.pom[INFO] Downloaded: https://repo.maven.apache.org/maven2/org/apache/maven/maven-parent/22/maven-parent-22.pom (30 KB at 61.3 KB/sec)[INFO] Downloading: https://repo.maven.apache.org/maven2/org/apache/apache/11/apache-11.pom[INFO] Downloaded: https://repo.maven.apache.org/maven2/org/apache/apache/11/apache-11.pom (15 KB at 45.3 KB/sec)....

Docker Build 的日志

$ kubectl -n tekton-pipelines logs -f build-app-task-run-pod-b8f890 -c build-step-build-docker-imageINFO[0000] Downloading base image tomcat2019/05/06 11:58:46 No matching credentials were found, falling back on anonymousINFO[0003] Taking snapshot of full filesystem...INFO[0003] Skipping paths under /builder/home, as it is a whitelisted directoryINFO[0003] Skipping paths under /builder/tools, as it is a whitelisted directoryINFO[0003] Skipping paths under /dev, as it is a whitelisted directoryINFO[0003] Skipping paths under /kaniko, as it is a whitelisted directoryINFO[0003] Skipping paths under /proc, as it is a whitelisted directoryINFO[0003] Skipping paths under /run/secrets/kubernetes.io/serviceaccount, as it is a whitelisted directoryINFO[0003] Skipping paths under /sys, as it is a whitelisted directoryINFO[0003] Skipping paths under /var/run, as it is a whitelisted directoryINFO[0003] Skipping paths under /workspace, as it is a whitelisted directoryINFO[0003] Using files from context: [/workspace/java-demo/target/demo.war]INFO[0003] ADD target/demo.war /usr/local/tomcat/webapps/demo.warINFO[0003] Taking snapshot of files......

app-deploy 的日志

$ kubectl -n tekton-pipelines logs -f build-app-task-run-pod-637855 -c build-step-deploy-appdeployment.extensions/jenkins-java-demo createdservice/jenkins-java-demo created

taskrun 的完成状态为 True 则构建部署过程完成

$ kubectl -n tekton-pipelines get taskrunNAME SUCCEEDED REASON STARTTIME COMPLETIONTIMEbuild-app-task-run True 4m 2m

小结

Tekton Pipeline 中的任务模板能够拿来复用，而不须要重复定义，另外经过 CRD 从新定义 CI/CD 是一大亮点。

参考文档

https://www.google.com
https://www.infoq.cn/article/tZ6E1_lhsWeh26C9xUJf
https://yq.aliyun.com/articles/701368?utm_content=g_1000055966
https://juejin.im/post/5d5a612a6fb9a06b2d77d39a