client-go中ClientSet调用Apply部署Deployment失败求助

问题原因 #

报错invalid object type: /, Kind=的核心原因是：直接实例化的DeploymentApplyConfiguration对象缺少APIVersion和Kind元数据。Server-Side Apply要求传入的对象必须明确自身资源类型，而ApplyConfiguration系列结构体不会像原生Deployment结构体那样自动填充这些字段，导致K8s API Server无法识别对象类型。

Create方法能成功是因为原生apps/v1.Deployment结构体默认包含APIVersion: "apps/v1"和Kind: "Deployment"元数据，API Server可直接识别。

解决方案 #

有两种修复方式：

方式1：使用官方构造函数初始化Apply配置 #

client-go为每个资源的ApplyConfiguration提供了构造函数，会自动填充正确的APIVersion和Kind：

deploymentApplyConfig := applyappsv1.Deployment(deploymentName, namespace).
    WithSpec(applyappsv1.DeploymentSpec().
        WithReplicas(3).
        WithSelector(applymetav1.LabelSelector().
            WithMatchLabels(map[string]string{"app": "test-app"})).
        WithTemplate(applycorev1.PodTemplateSpec().
            WithLabels(map[string]string{"app": "test-app"}).
            WithSpec(applycorev1.PodSpec().
                WithContainers(applycorev1.Container().
                    WithName("nginx").
                    WithImage("nginx:1.14.2").
                    WithPorts(applycorev1.ContainerPort().WithContainerPort(80))))))

方式2：手动添加元数据 #

若坚持直接实例化结构体，需手动设置APIVersion和Kind字段：

deploymentApplyConfig := applyappsv1.DeploymentApplyConfiguration{
    ObjectMetaApplyConfiguration: &applymetav1.ObjectMetaApplyConfiguration{
        Name:      &deploymentName,
        Namespace: &namespace,
    },
    // 必须添加以下两行
    APIVersion: pointer.String("apps/v1"),
    Kind:       pointer.String("Deployment"),
    Spec: &applyappsv1.DeploymentSpecApplyConfiguration{
        Replicas: pointer.Int32(3),
        Selector: &applymetav1.LabelSelectorApplyConfiguration{
            MatchLabels: map[string]string{
                "app": "test-app",
            },
        },
        Template: &applycorev1.PodTemplateSpecApplyConfiguration{
            ObjectMetaApplyConfiguration: &applymetav1.ObjectMetaApplyConfiguration{
                Labels: map[string]string{
                    "app": "test-app",
                },
            },
            Spec: &applycorev1.PodSpecApplyConfiguration{
                Containers: []applycorev1.ContainerApplyConfiguration{
                    {
                        Name:  pointer.String("nginx"),
                        Image: pointer.String("nginx:1.14.2"),
                        Ports: []applycorev1.ContainerPortApplyConfiguration{
                            {
                                ContainerPort: pointer.Int32(80),
                            },
                        },
                    },
                },
            },
        },
    },
}

验证修复 #

修改后重新运行代码，Apply方法即可正常识别Deployment资源类型，完成Server-Side Apply操作。

内容的提问来源于stack exchange，提问作者grooby