Go语言的k8s开发-02-Namespace操作

1. 结构体

1.1 NamespaceList

所在包："k8s.io/api/core/v1"

type NamespaceList struct {
    v1.TypeMeta `json:",inline"`
    v1.ListMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
    Items           []Namespace `json:"items" protobuf:"bytes,2,rep,name=items"`
}

其中Items的各元素结构体Namespace 如下：

1.2 Namespace

所在包："k8s.io/api/core/v1"

type Namespace struct {
    v1.TypeMeta   `json:",inline"`
    v1.ObjectMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
    Spec              NamespaceSpec   `json:"spec,omitempty" protobuf:"bytes,2,opt,name=spec"`
    Status            NamespaceStatus `json:"status,omitempty" protobuf:"bytes,3,opt,name=status"`

其中各成员结构体如下：

1.3 TypeMeta

所在包 "k8s.io/apimachinery/pkg/apis/meta/v1"

Package:
v1
type TypeMeta struct {
    Kind       string `json:"kind,omitempty" protobuf:"bytes,1,opt,name=kind"`
    APIVersion string `json:"apiVersion,omitempty" protobuf:"bytes,2,opt,name=apiVersion"`
}

对应k8s的yml文件中的如下部分

apiVersion: v1
kind: Namespace

1.4 ObjectMeta

所在包 "k8s.io/apimachinery/pkg/apis/meta/v1"

type ObjectMeta struct {
    Name                       string               `json:"name,omitempty" protobuf:"bytes,1,opt,name=name"`
    GenerateName               string               `json:"generateName,omitempty" protobuf:"bytes,2,opt,name=generateName"`
    Namespace                  string               `json:"namespace,omitempty" protobuf:"bytes,3,opt,name=namespace"`
    SelfLink                   string               `json:"selfLink,omitempty" protobuf:"bytes,4,opt,name=selfLink"`
    UID                        types.UID            `json:"uid,omitempty" protobuf:"bytes,5,opt,name=uid,casttype=k8s.io/kubernetes/pkg/types.UID"`
    ResourceVersion            string               `json:"resourceVersion,omitempty" protobuf:"bytes,6,opt,name=resourceVersion"`
    Generation                 int64                `json:"generation,omitempty" protobuf:"varint,7,opt,name=generation"`
    CreationTimestamp          Time                 `json:"creationTimestamp,omitempty" protobuf:"bytes,8,opt,name=creationTimestamp"`
    DeletionTimestamp          *Time                `json:"deletionTimestamp,omitempty" protobuf:"bytes,9,opt,name=deletionTimestamp"`
    DeletionGracePeriodSeconds *int64               `json:"deletionGracePeriodSeconds,omitempty" protobuf:"varint,10,opt,name=deletionGracePeriodSeconds"`
    Labels                     map[string]string    `json:"labels,omitempty" protobuf:"bytes,11,rep,name=labels"`
    Annotations                map[string]string    `json:"annotations,omitempty" protobuf:"bytes,12,rep,name=annotations"`
    OwnerReferences            []OwnerReference     `json:"ownerReferences,omitempty" patchStrategy:"merge" patchMergeKey:"uid" protobuf:"bytes,13,rep,name=ownerReferences"`
    Finalizers                 []string             `json:"finalizers,omitempty" patchStrategy:"merge" protobuf:"bytes,14,rep,name=finalizers"`
    ManagedFields              []ManagedFieldsEntry `json:"managedFields,omitempty" protobuf:"bytes,17,rep,name=managedFields"`
}

对应k8s的yml文件如下部分

metadata:
  ……

1.5 NamespaceSpec

所在包："k8s.io/api/core/v1"

type NamespaceSpec struct {
    Finalizers []FinalizerName `json:"finalizers,omitempty" protobuf:"bytes,1,rep,name=finalizers,casttype=FinalizerName"`
}

对应k8s的yml文件如下部分

spec:
  ……

Namespace 的这一部分在使用中意义并不大

1.6 NamespaceStatus

所在包："k8s.io/api/core/v1"

type NamespaceStatus struct {
    Phase      NamespacePhase       `json:"phase,omitempty" protobuf:"bytes,1,opt,name=phase,casttype=NamespacePhase"`
    Conditions []NamespaceCondition `json:"conditions,omitempty" patchStrategy:"merge" patchMergeKey:"type" protobuf:"bytes,2,rep,name=conditions"`
}

对应k8s的yml文件如下部分

status:
  phase: Active

1.7 对照yml文件示例

附原生k8s集群上一个namespace 信息，大家可以对照理解一下以上结构体

apiVersion: v1
kind: Namespace
metadata:
  annotations:
    cattle.io/status: '{"Conditions":[{"Type":"ResourceQuotaInit","Status":"True","Message":"","LastUpdateTime":"2022-09-28T05:22:19Z"},{"Type":"InitialRolesPopulated","Status":"True","Message":"","LastUpdateTime":"2022-09-28T05:22:19Z"}]}'
    lifecycle.cattle.io/create.namespace-auth: "true"
  creationTimestamp: "2022-09-28T05:23:29Z"
  finalizers:
  - controller.cattle.io/namespace-auth
  labels:
    kubernetes.io/metadata.name: liubei
  name: liubei
  resourceVersion: "19106479"
  selfLink: /api/v1/namespaces/liubei
  uid: 0aa2122e-2244-44cf-ba55-0437f50e2ff3
spec:
  finalizers:
  - kubernetes
status:
  phase: Active

2. Namespace List

语法

• 语法

func (NamespaceInterface) List(ctx context.Context, opts v1.ListOptions) (*v1.NamespaceList, error)

• 语法示例

namespaceList,err = clientSet.CoreV1().Namespaces().List(context.TODO(), metaV1.ListOptions{})

完整示例

• 定义函数

package crowK8S

import (
    "context"
    coreV1 "k8s.io/api/core/v1"
    metaV1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes"
)

func GetNamespaceList(clientSet *kubernetes.Clientset)(namespaceList *coreV1.NamespaceList,err error)  {
    namespaceList,err = clientSet.CoreV1().Namespaces().List(context.TODO(), metaV1.ListOptions{})
    if err != nil {
        return namespaceList,err
    }
    return namespaceList,nil
}

• 调用示例

package main

import (
    "fmt"
    "go-k8s/crowK8S"
)

func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }

    namespaceList,err := crowK8S.GetNamespaceList(clientSet)
    if err !=nil {
        fmt.Println(err)
    }
    for _,namespace := range namespaceList.Items {
        fmt.Printf("%+v\n",namespace.Name)
    }
}

• 结果

cattle-system
crust-v3x-sit
default
kube-node-lease
kube-public
kube-system
……

3. Get Namespace

语法

• 语法

func (NamespaceInterface) Get(ctx context.Context, name string, opts v1.GetOptions) (*v1.Namespace, error)

• 语法示例

namespaceInfo,err = clientSet.CoreV1().Namespaces().Get(context.TODO(),namespaceName,metaV1.GetOptions{})

完整示例

• 函数

package crowK8S

import (
    "context"
    coreV1 "k8s.io/api/core/v1"
    metaV1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes"
)
func GetNamespace(clientSet *kubernetes.Clientset,namespaceName string)(namespaceInfo *coreV1.Namespace,err error)  {
    namespaceInfo,err = clientSet.CoreV1().Namespaces().Get(context.TODO(),namespaceName,metaV1.GetOptions{})
    if err != nil {
        return namespaceInfo,err
    }
    return namespaceInfo,nil
}

• 调用

package main

import (
    "fmt"
    "go-k8s/crowK8S"
)

func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }

    namespaceInfo,err := crowK8S.GetNamespace(clientSet,"kube-system")
    if err !=nil {
        fmt.Printf("%+v\n",namespaceInfo)
    }

}

• 结果

&Namespace{ObjectMeta:{kube-system   /api/v1/namespaces/kube-system 273b218d-5a59-411d-8950-ab150b4e176a 6700369 0 2022-07-12 16:41:31 +0800 CST   map[field.cattle.io/projectId:p-qc5f4 kubernetes.io/metadata.name:kube-system] map[cattle.io/status:{"Conditions":[{"Type":"ResourceQuotaInit","Status":"True","Message":"","LastUpdateTime":"2022-08-12T08:41:05Z"},{"Type":"InitialRolesPopulated","Status":"True","Message":"","LastUpdateTime":"2022-08-12T08:41:10Z"}]} field.cattle.io/projectId:c-c8rsj:p-qc5f4 lifecycle.cattle.io/create.namespace-auth:true] [] [controller.cattle.io/namespace-auth] [{kube-apiserver Update v1 2022-07-12 16:41:31 +0800 CST FieldsV1 {"f:metadata":{"f:labels":{".":{},"f:kubernetes.io/metadata.name":{}}}} } {rancher Update v1 2022-08-12 16:42:15 +0800 CST FieldsV1 {"f:metadata":{"f:annotations":{".":{},"f:cattle.io/status":{},"f:field.cattle.io/projectId":{},"f:lifecycle.cattle.io/create.namespace-auth":{}},"f:finalizers":{".":{},"v:\"controller.cattle.io/namespace-auth\"":{}}}} } {agent Update v1 2022-08-12 16:42:40 +0800 CST FieldsV1 {"f:metadata":{"f:labels":{"f:field.cattle.io/projectId":{}}}} }]},Spec:NamespaceSpec{Finalizers:[kubernetes],},Status:NamespaceStatus{Phase:Active,Conditions:[]NamespaceCondition{},},}

4. Create Namespace

• 创建namespace的yml文件如下：

apiVersion: v1
kind: Namespace
metadata:
  name: liubei

kind和apiVersionSDK会给我们补充上，因此我们只需要填上名字即可

语法

• 语法

func (NamespaceInterface) Create(ctx context.Context, namespace *v1.Namespace, opts v1.CreateOptions) (*v1.Namespace, error)

• 语法示例

namespaceInfo,err = clientSet.CoreV1().Namespaces().Create(context.TODO(),&namespace,metaV1.CreateOptions{})

完整示例

• 创建函数

package crowK8S

import (
    "context"
    coreV1 "k8s.io/api/core/v1"
    metaV1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes"
)

func CreateNamespace(clientSet *kubernetes.Clientset,namespaceName string)(namespaceInfo *coreV1.Namespace,err error)  {
    var namespace coreV1.Namespace
    namespace.Name = namespaceName
    namespaceInfo,err = clientSet.CoreV1().Namespaces().Create(context.TODO(),&namespace,metaV1.CreateOptions{})
    if err != nil {
        return namespaceInfo,err
    }
    return namespaceInfo,nil
}

• 引用

package main

import (
    "fmt"
    "go-k8s/crowK8S"
)

func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }

    namespaceInfo,err := crowK8S.CreateNamespace(clientSet,"liubei")
    if err !=nil {
        fmt.Println(err)
    }
    fmt.Printf("%+v\n",namespaceInfo)
}

• 输出

&Namespace{ObjectMeta:{liubei   /api/v1/namespaces/liubei 68ae5eca-13a7-4720-b636-789a3b1776d2 19055960 0 2022-09-28 08:52:32 +0800 CST   map[kubernetes.io/metadata.name:liubei] map[] [] [] [{___6go_build_main_go.exe Update v1 2022-09-28 08:52:32 +0800 CST FieldsV1 {"f:metadata":{"f:labels":{".":{},"f:kubernetes.io/metadata.name":{}}}} }]},Spec:NamespaceSpec{Finalizers:[kubernetes],},Status:NamespaceStatus{Phase:Active,Conditions:[]NamespaceCondition{},},}

5. Delete Namespace

语法

• 语法

func (NamespaceInterface) Delete(ctx context.Context, name string, opts v1.DeleteOptions) error

• 语法示例

err = clientSet.CoreV1().Namespaces().Delete(context.TODO(),namespaceName,metaV1.DeleteOptions{})

完整示例

• 创建函数

package crowK8S

import (
    "context"
    coreV1 "k8s.io/api/core/v1"
    metaV1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes"
)
func DeleteNamespace(clientSet *kubernetes.Clientset,namespaceName string)(err error)  {
    err = clientSet.CoreV1().Namespaces().Delete(context.TODO(),namespaceName,metaV1.DeleteOptions{})
    if err != nil {
        return err
    }
    return nil
}

• 引用

package main

import (
    "fmt"
    "go-k8s/crowK8S"
)

func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }

    err = crowK8S.DeleteNamespace(clientSet,"liubei")
    if err !=nil {
        fmt.Println(err)
    }

}

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