Go语言开发k8s之ConfigMap操作解析

1. 结构体

1.1 ConfigMapList

所在包："k8s.io/api/core/v1"

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

Items中每个ConfigMap结构体如下：

1.2 ConfigMap

所在包："k8s.io/api/core/v1"

type ConfigMap struct {
    v1.TypeMeta   `json:",inline"`
    v1.ObjectMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
    Immutable         *bool             `json:"immutable,omitempty" protobuf:"varint,4,opt,name=immutable"`
    Data              map[string]string `json:"data,omitempty" protobuf:"bytes,2,rep,name=data"`
    BinaryData        map[string][]byte `json:"binaryData,omitempty" protobuf:"bytes,3,rep,name=binaryData"`
}

其成员说明如下：

1.3 TypeMeta

所在包："k8s.io/apimachinery/pkg/apis/meta/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"`
}

对应在k8s上创建service的yml文件的如下部分：

apiVersion: v1
kind: ConfigMap

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"`
}

对应在k8s上创建service的yml文件的如下部分：

metadata:
  name: nginxconf
  namespace: test

1.7 对照yml文件示例

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

apiVersion: v1
data:
  nginx.conf: |2-
        worker_processes  1;
        events {
            worker_connections  1024;
        }
        http {
            include       mime.types;
            default_type  application/octet-stream;
            client_max_body_size 50m;
            sendfile        on;
            keepalive_timeout  65;
            server {
                listen       80;
                server_name  localhost;
                root   /usr/share/nginx/html;
                location / {
                   index  index.html index.htm;
                }
            }
        }
kind: ConfigMap
metadata:
  creationTimestamp: "2022-10-14T06:53:14Z"
  name: nginxconf
  namespace: liubei
  resourceVersion: "23364643"
  selfLink: /api/v1/namespaces/liubei/configmaps/nginxconf
  uid: cbe236fb-b86b-47f5-bf13-696fada4e400

1.5 Immutable

bool值的指针

true，不可更改
否则可以随时更改

1.6 Data

map[string]string类型，对应yaml文件中的data字段，每一个成员对应一个键值对，即一个要挂载的配置文件

1.7 BinaryData

map[string][]byte类型，和Data类似，只不过传入的字串变成了[]byte

2. Create configMap

语法

func (ConfigMapInterface) Create(ctx context.Context, configMap *v1.ConfigMap, opts v1.CreateOptions) (*v1.ConfigMap, error)

语法示例

configMapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Create(context.TODO(),configMap,metaV1.CreateOptions{})

完整示例

之前一个k8s上nginx服务的configmap如下

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginxconf
  namespace: test
data:
  nginx.conf: |
    worker_processes  1;
    events {
        worker_connections  1024;
    }
    http {
        include       mime.types;
        default_type  application/octet-stream;
        client_max_body_size 50m;
        sendfile        on;
        keepalive_timeout  65;
        server {
            listen       80;
            server_name  localhost;
            root   /usr/share/nginx/html;
            location / {
               index  index.html index.htm;
            }
        }
    }

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 CreateConfigMap(clientSet *kubernetes.Clientset,namespaceName string,configMapName string,dataInfo string)(configMapInfo *coreV1.ConfigMap,err  error)  {
    configMap := &amp;coreV1.ConfigMap{
        ObjectMeta: metaV1.ObjectMeta{
            Name: configMapName,
        },
        Data: map[string]string{
            "nginx.conf" : dataInfo,
        },
    }
    configMapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Create(context.TODO(),configMap,metaV1.CreateOptions{})
    if err != nil {
        return configMapInfo,err
    }
    return configMapInfo,nil
}

调用函数

package main
import (
    "fmt"
    "go-k8s/crowK8S"
)
func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }
    var dataInfo string
    dataInfo = "    worker_processes  1;\n    events {\n        worker_connections  1024;\n    }\n    http {\n        include       mime.types;\n        default_type  application/octet-stream;\n        client_max_body_size 50m;\n        sendfile        on;\n        keepalive_timeout  65;\n        server {\n            listen       80;\n            server_name  localhost;\n            root   /usr/share/nginx/html;\n            location / {\n               index  index.html index.htm;\n            }\n        }\n    }"
    configMapInfo,err := crowK8S.CreateConfigMap(clientSet ,"liubei","nginxconf",dataInfo)
    fmt.Println(configMapInfo)
}

k8s上查看结果如下

[root@crust-m01 ~]# kubectl describe -n liubei configmaps nginxconf
Name:         nginxconf
Namespace:    liubei
Labels:       &lt;none&gt;
Annotations:  &lt;none&gt;
Data
====
nginx.conf:
----
    worker_processes  1;
    events {
        worker_connections  1024;
    }
    http {
        include       mime.types;
        default_type  application/octet-stream;
        client_max_body_size 50m;
        sendfile        on;
        keepalive_timeout  65;
        server {
            listen       80;
            server_name  localhost;
            root   /usr/share/nginx/html;
            location / {
               index  index.html index.htm;
            }
        }
    }
Events:  &lt;none&gt;

3. Get ConfigMapList

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 GetConfigMapList(clientSet *kubernetes.Clientset,namespaceName string)(configMapList *coreV1.ConfigMapList,err error)  {
    configMapList,err = clientSet.CoreV1().ConfigMaps(namespaceName).List(context.TODO(), metaV1.ListOptions{})
    if err != nil{
        return nil, err
    }
    return configMapList, err
}

使用函数

package main
import (
    "fmt"
    "go-k8s/crowK8S"
)
func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }
    configMapList,err := crowK8S.GetConfigMapList(clientSet ,"liubei")
    if err != nil {
        fmt.Println(err)
    }
    fmt.Println(configMapList)
}

结果打印

&ConfigMapList{ListMeta:{/api/v1/namespaces/liubei/configmaps 22893420 <nil>},Items:[]ConfigMap{ConfigMap{ObjectMeta:{kube-root-ca.crt liubei /api/v1/namespaces/liubei/configmaps/kube-root-ca.crt ecb54dbb-3082-4caa-9055-8061e5d9d7b6 19106476 0 2022-09-28 13:23:29 +0800 CST <nil> <nil> map[] map[] [] [] [{kube-controller-manager Update v1 2022-09-28 13:23:29 +0800 CST FieldsV1 {"f:data":{".":{},"f:ca.crt":{}}} }]},Data:map[string]string{ca.crt: -----BEGIN CERTIFICATE-----
MIIC6TCCAdGgAwIBAgIBADANBgkqhkiG9w0BAQsFADAVMRMwEQYDVQQDEwprdWJl
cm5ldGVzMCAXDTIyMDcxMjA4NDExNFoYDzIxMjIwNjE4MDg0MTE0WjAVMRMwEQYD
VQQDEwprdWJlcm5ldGVzMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA
85IYxSiow4zNifU1yqMK6knWrJIErQXD6zHUgpAk2Z/c3XfpwONCkTObLEhXJKeN
9wjqOAxx9OLFSqZdefnOjSKw6jZJFC6APLM/bdsX4ECnlg32edQ05iUZxPYZjpdS
BhpbdK4jCirB/XMgdmJizxoR1NHBZNHGbnH0rabfF/PrVrZQdUJpLpoAvOyT3bWr
+HPSHA7mzODAko/RtVGyGoZClBZbFds7f1cyY2JGOB6GqrJMmLVf3xBVGwUO3KLA
0lZ/rfPrS9fEzAD6y1pqke7wr9agrFXWhFZLtwIVqGrt6Zzrq0jxamwPqZsYAXPm
jA3LYX0VnseIJTGX0S9HKQIDAQABo0IwQDAOBgNVHQ8BAf8EBAMCAqQwDwYDVR0T
AQH/BAUwAwEB/zAdBgNVHQ4EFgQUExxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
hvcNAQELBQADggEBANgTtUROUKrLcihbTJXrhZKo94Q/WX7AeRVz7HlWTEqWFsX1
eZyFNMPeFoswLwGe4nwuS2Nd+WvE+WPZ/0CF+q8/0oGE6B87zdTnJJELTnIqnWIm
k+ac7gMokk7EaCv30FBDX239E++zVooWsHj3Tc1dmn2AY+whgNXnxT9TGNst9o2z
DTlzI2VWg8kay3IhZS0NjsKk1YMbd8c+5uLQZwWEtGa7HlD8ooOF/emOINVIbRH4
T7LiVjQH3JJPZtYSWnl88IMtXlW360oABkVdKY4Z1nNzrNWBCGOFQ4Y75XmFY6Qi
2c0f8L2WtTFdrXgbbHCbOaIj9rruEH5wKxjxBg8=
-----END CERTIFICATE-----
,},BinaryData:map[string][]byte{},Immutable:nil,},ConfigMap{ObjectMeta:{nginxconf liubei /api/v1/namespaces/liubei/configmaps/nginxconf 395535db-1df7-408a-9976-18e6ded1207e 22854355 0 2022-10-12 17:21:03 +0800 CST <nil> <nil> map[] map[] [] [] [{___go_build_main_go.exe Update v1 2022-10-12 17:21:03 +0800 CST FieldsV1 {"f:data":{".":{},"f:nginx.conf":{}}} }]},Data:map[string]string{nginx.conf: worker_processes 1;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
client_max_body_size 50m;
sendfile on;
keepalive_timeout 65;
server {
listen 80;
server_name localhost;
root /usr/share/nginx/html;
location / {
index index.html index.htm;
}
}
},},BinaryData:map[string][]byte{},Immutable:nil,},},}

4. Get ConfigMap

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

语法示例

configmapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Get(context.TODO(),configMapName,metaV1.GetOptions{})

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 GetConfigMap(clientSet *kubernetes.Clientset,namespaceName string,configMapName string)(configmapInfo *coreV1.ConfigMap,err error)  {
    configmapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Get(context.TODO(), configMapName,metaV1.GetOptions{})
    if err != nil{
        return nil, err
    }
    return configmapInfo, err
}

调用

package main
import (
    "fmt"
    "go-k8s/crowK8S"
)
func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }
    configmapInfo,err := crowK8S.GetConfigMap(clientSet ,"liubei","nginxconf")
    if err != nil {
        fmt.Println(err)
    }
    fmt.Println(configmapInfo)
}

结果

&ConfigMap{ObjectMeta:{nginxconf liubei /api/v1/namespaces/liubei/configmaps/nginxconf 395535db-1df7-408a-9976-18e6ded1207e 22854355 0 2022-10-12 17:21:03 +0800 CST <nil> <nil> map[] map[] [] [] [{___go_build_main_go.exe Update v1 2022-10-12 17:21:03 +0800 CST FieldsV1 {"f:data":{".":{},"f:nginx.conf":{}}} }]},Data:map[string]string{nginx.conf: worker_processes 1;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
client_max_body_size 50m;
sendfile on;
keepalive_timeout 65;
server {
listen 80;
server_name localhost;
root /usr/share/nginx/html;
location / {
index index.html index.htm;
}
}
},},BinaryData:map[string][]byte{},Immutable:nil,}

5. Update ConfigMap

func (ConfigMapInterface) Update(ctx context.Context, configMap *v1.ConfigMap, opts v1.UpdateOptions) (*v1.ConfigMap, error)

语法示例

configmapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Update(context.TODO(),configmapInfo,metaV1.UpdateOptions{})

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 ApplyConfigMap(clientSet *kubernetes.Clientset,namespaceName string,configMapName string,fileName string,configMapData string)(configmapInfo *coreV1.ConfigMap,err error)  {
    configmapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Get(context.TODO(), configMapName,metaV1.GetOptions{})
    if err != nil{
        return nil, err
    }
    configmapInfo.Data[fileName] = configMapData
    configmapInfo,err = clientSet.CoreV1().ConfigMaps(namespaceName).Update(context.TODO(),configmapInfo,metaV1.UpdateOptions{})
    if err !=nil {
        return configmapInfo,err
    }
    return configmapInfo,nil
}

调用

func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }
    configMapInfo,err := crowK8S.ApplyConfigMap(clientSet ,"liubei","nginxconf","nginx.conf","hello world")
    fmt.Println(configMapInfo)
}

结果打印

&ConfigMap{ObjectMeta:{nginxconf liubei /api/v1/namespaces/liubei/configmaps/nginxconf 395535db-1df7-408a-9976-18e6ded1207e 22901163 0 2022-10-12 17:21:03 +0800 CST <nil> <nil> map[] map[] [] [] [{___go_build_main_go.exe Update v1 2022-10-12 17:21:03 +0800 CST FieldsV1 {"f:data":{".":{},"f:nginx.conf":{}}} }]},Data:map[string]string{nginx.conf: hello world,},BinaryData:map[string][]byte{},Immutable:nil,}

k8s上查看结果

[root@crust-m01 ~]# kubectl describe -n liubei configmaps nginxconf
Name:         nginxconf
Namespace:    liubei
Labels:       <none>
Annotations:  <none>
Data
====
nginx.conf:
----
hello world
Events:  <none>

6. Delete ConfigMap

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

语法示例

err = clientSet.CoreV1().ConfigMaps(namespaceName).Delete(context.TODO(),configMapName,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 DeleteConfigMap(clientSet *kubernetes.Clientset,namespaceName string,configMapName string)(err error)  {
    err = clientSet.CoreV1().ConfigMaps(namespaceName).Delete(context.TODO(),configMapName,metaV1.DeleteOptions{})
    if err != nil {
        return err
    }
    return nil
}

调用

package main
import (
    "fmt"
    "go-k8s/crowK8S"
)
func main()  {
    clientSet,err := crowK8S.ConnectK8s()
    if err !=nil {
        fmt.Println(err)
    }
    err = crowK8S.DeleteConfigMap(clientSet,"liubei","nginxconf")
    if err != nil {
        fmt.Println(err)
    }else {
        fmt.Println("删除成功")
    }
}

结果打印

删除成功

Go语言开发k8s之ConfigMap操作解析_Golang

目录

1. 结构体

1.1 ConfigMapList

1.2 ConfigMap

1.3 TypeMeta

1.4 ObjectMeta

1.7 对照yml文件示例

1.5 Immutable

1.6 Data

1.7 BinaryData

2. Create configMap

语法

完整示例

3. Get ConfigMapList

完整示例

4. Get ConfigMap

完整示例

5. Update ConfigMap

完整示例

6. Delete ConfigMap

完整示例