[DevOps] Jenkins로 Kubernetes yaml 파싱 에러

Jenkins에서 k8s로 배포하기 위해 Kubernetes Continuous Deploy 라는 플러그인을 사용하고 있었다.

 

그런데 최신으로 업데이트를 하고 난 뒤 다음과 같은 에러가 발생했다.

ERROR: ERROR: Can't construct a java object for tag:yaml.org,2002:io.kubernetes.client.openapi.models.V1Deployment; exception=Class not found: io.kubernetes.client.openapi.models.V1Deployment
 in 'reader', line 1, column 1:
    apiVersion: apps/v1
    ^

hudson.remoting.ProxyException: Can't construct a java object for tag:yaml.org,2002:io.kubernetes.client.openapi.models.V1Deployment; exception=Class not found: io.kubernetes.client.openapi.models.V1Deployment
 in 'reader', line 1, column 1:
    apiVersion: apps/v1
    ^

	at org.yaml.snakeyaml.constructor.Constructor$ConstructYamlObject.construct(Constructor.java:335)
	at org.yaml.snakeyaml.constructor.BaseConstructor.constructObjectNoCheck(BaseConstructor.java:229)
	at org.yaml.snakeyaml.constructor.BaseConstructor.constructObject(BaseConstructor.java:219)
	at io.kubernetes.client.util.Yaml$CustomConstructor.constructObject(Yaml.java:337)
	at org.yaml.snakeyaml.constructor.BaseConstructor.constructDocument(BaseConstructor.java:173)
	at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:157)
	at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:490)
	at org.yaml.snakeyaml.Yaml.loadAs(Yaml.java:456)
	at io.kubernetes.client.util.Yaml.loadAs(Yaml.java:224)
	at io.kubernetes.client.util.Yaml.modelMapper(Yaml.java:494)
	at io.kubernetes.client.util.Yaml.loadAll(Yaml.java:272)
	at com.microsoft.jenkins.kubernetes.wrapper.KubernetesClientWrapper.apply(KubernetesClientWrapper.java:236)
	at com.microsoft.jenkins.kubernetes.command.DeploymentCommand$DeploymentTask.doCall(DeploymentCommand.java:172)
	at com.microsoft.jenkins.kubernetes.command.DeploymentCommand$DeploymentTask.call(DeploymentCommand.java:124)
	at com.microsoft.jenkins.kubernetes.command.DeploymentCommand$DeploymentTask.call(DeploymentCommand.java:106)
	at hudson.FilePath.act(FilePath.java:1163)
	at com.microsoft.jenkins.kubernetes.command.DeploymentCommand.execute(DeploymentCommand.java:68)
	at com.microsoft.jenkins.kubernetes.command.DeploymentCommand.execute(DeploymentCommand.java:45)
	at com.microsoft.jenkins.azurecommons.command.CommandService.runCommand(CommandService.java:88)
	at com.microsoft.jenkins.azurecommons.command.CommandService.execute(CommandService.java:96)
	at com.microsoft.jenkins.azurecommons.command.CommandService.executeCommands(CommandService.java:75)
	at com.microsoft.jenkins.azurecommons.command.BaseCommandContext.executeCommands(BaseCommandContext.java:77)
	at com.microsoft.jenkins.kubernetes.KubernetesDeploy.perform(KubernetesDeploy.java:42)
	at jenkins.tasks.SimpleBuildStep.perform(SimpleBuildStep.java:112)
	at hudson.tasks.BuildStepCompatibilityLayer.perform(BuildStepCompatibilityLayer.java:78)
	at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
	at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:741)
	at hudson.model.Build$BuildExecution.build(Build.java:206)
	at hudson.model.Build$BuildExecution.doRun(Build.java:163)
	at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:504)
	at hudson.model.Run.execute(Run.java:1894)
	at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
	at hudson.model.ResourceController.execute(ResourceController.java:97)
	at hudson.model.Executor.run(Executor.java:428)
Caused by: hudson.remoting.ProxyException: org.yaml.snakeyaml.error.YAMLException: Class not found: io.kubernetes.client.openapi.models.V1Deployment
	at org.yaml.snakeyaml.constructor.Constructor.getClassForNode(Constructor.java:664)
	at org.yaml.snakeyaml.constructor.Constructor$ConstructYamlObject.getConstructor(Constructor.java:322)
	at org.yaml.snakeyaml.constructor.Constructor$ConstructYamlObject.construct(Constructor.java:331)
	... 33 more
ERROR: Kubernetes deployment ended with HasError

해당 플러그인 깃헙 이슈에서 찾아보니 다운그레이드를 하면 된다고 했지만

 

막상 시도를 해보니 의존성으로 인하여 모든 플러그인들을 다운그레이드를 해야했다.

 

그래서 다른 방법을 찾다가 Jackson 2 API에서 snakeyaml 에 대한 의존성을 추가해서 발생한 문제라는 것을 알게되었다.

 

이를 해결하기 위해 다음 부분을 주석하여 빌드한 뒤 jenkins에 설치해보니 에러없이 잘 동작하는 것을 확인할 수 있었다.

 

github.com/jenkinsci/jackson2-api-plugin/blob/master/pom.xml#L149-L164

...
    <dependency>
      <groupId>com.fasterxml.jackson.dataformat</groupId>
      <artifactId>jackson-dataformat-yaml</artifactId>
      <version>${jackson.version}</version>
      <exclusions>
        <exclusion>
          <groupId>org.yaml</groupId>
          <artifactId>snakeyaml</artifactId>
        </exclusion>
      </exclusions>
    </dependency>

    <dependency>
      <groupId>io.jenkins.plugins</groupId>
      <artifactId>snakeyaml-api</artifactId>
    </dependency>
 ...

 

참고 문헌

1. plugins.jenkins.io/kubernetes-cd/

2. https://github.com/jenkinsci/kubernetes-cd-plugin/issues/134

3. https://github.com/jenkinsci/jackson2-api-plugin