项目主要是通过client-go来与kubernetes集群进行连接，并对集群进行增删改查操作。同时也对操作进行restful api的暴露。
本身也增加集群模块，用于保存不同集群的访问信息，包含对集群的操作，与对集群资源对象的增删改查进行结合。
client-go简介
client-go客户端
client-go是一个调用kubernetes集群资源对象API的客户端，即通过client-go实现对kubernetes集群中资源对象（包括deployment、service、ingress、replicaSet、pod、namespace、node和CRD等）的增删改查等操作。大部分对kubernetes进行前置API封装的二次开发都通过client-go这个第三方包来实现。
client-go不仅被k8s进行使用，其他围绕k8s的生态也被大量使用，例如：kubectl ETCD-operator等。 client-go一共提供了4种与kubernetes APIServer交互的客户端对象，分别为RESTClient，DiscoveryClient，ClientSet，DynamicClient。
RESTClient是最基础的客户端。RESTClient对HTTP Request进行了封装，实现了RESTful风格的API。ClientSet、DynamicClient及DiscoveryClient客户端都是基于RESTClient实现的。
ClientSet在RESTClient的基础上封装了对Resource和Version的管理方法。每一个Resource可以理解为一个客户端，而ClientSet则是多个客户端的集合，每一个Resource和Version都以函数的方式暴露给开发者。ClientSet只能够处理Kubernetes内置资源，它是通过client-gen代码生成器自动生成的。
DynamicClient与ClientSet最大的不同之处是，ClientSet仅能访问Kubernetes自带的资源（即Client集合内的资源），不能直接访问CRD自定义资源。DynamicClient能够处理Kubernetes中的所有资源对象，包括Kubernetes内置资源与CRD自定义资源。
DiscoveryClient发现客户端，用于发现kube-apiserver所支持的资源组、资源版本、资源信息（即Group、Versions、Resources）。
client-go对kubernetes资源对象的调用，需要先获取kubernetes的配置信息，即$HOME/.kube/config。
整个调用的过程如下：
kubeconfig→rest.config→clientset→具体的client(CoreV1Client)→具体的资源对象(pod)→RESTClient→http.Client→HTTP请求的发送及响应
通过clientset中不同的client和client中不同资源对象的方法实现对kubernetes中资源对象的增删改查等操作，常用的client有CoreV1Client、AppsV1beta1Client、ExtensionsV1beta1Client等。
kubeconfig
kubeconfig用于管理访问集群Kube-apiserver的配置信息。上面介绍的几个客户端都通过kubeconfig来访问集群，其步骤可分为两步：
●第1步，加载kubeconfig配置信息；
●第2步，合并多个kubeconfig配置信息
http://k8s.io)\client-go\tools\clientcmd\loader.go源码位置：staging\src[k8s.io](
func (rules *ClientConfigLoadingRules) Load() (*clientcmdapi.Config, error) {
if err := rules.Migrate(); err != nil {
return nil, err
}
errlist := []error{}
missingList := []string{}
kubeConfigFiles := []string{}
// Make sure a file we were explicitly told to use exists
if len(rules.ExplicitPath) > 0 {
if _, err := os.Stat(rules.ExplicitPath); os.IsNotExist(err) {
return nil, err
}
kubeConfigFiles = append(kubeConfigFiles, rules.ExplicitPath)
} else {
kubeConfigFiles = append(kubeConfigFiles, rules.Precedence...)
}
kubeconfigs := []*clientcmdapi.Config{}
// read and cache the config files so that we only look at them once
for _, filename := range kubeConfigFiles {
if len(filename) == 0 {
// no work to do
continue
}
config, err := LoadFromFile(filename)
if os.IsNotExist(err) {
// skip missing files
// Add to the missing list to produce a warning
missingList = append(missingList, filename)
continue
}
if err != nil {
errlist = append(errlist, fmt.Errorf("error loading config file \"%s\": %v", filename, err))
continue
}
kubeconfigs = append(kubeconfigs, config)
}
if rules.WarnIfAllMissing && len(missingList) > 0 && len(kubeconfigs) == 0 {
klog.Warningf("Config not found: %s", strings.Join(missingList, ", "))
}
// first merge all of our maps
mapConfig := clientcmdapi.NewConfig()
for _, kubeconfig := range kubeconfigs {
mergo.MergeWithOverwrite(mapConfig, kubeconfig)
}
// merge all of the struct values in the reverse order so that priority is given correctly
// errors are not added to the list the second time
nonMapConfig := clientcmdapi.NewConfig()
for i := len(kubeconfigs) - 1; i >= 0; i-- {
kubeconfig := kubeconfigs[i]
mergo.MergeWithOverwrite(nonMapConfig, kubeconfig)
}
// since values are overwritten, but maps values are not, we can merge the non-map config on top of the map config and
// get the values we expect.
config := clientcmdapi.NewConfig()
mergo.MergeWithOverwrite(config, mapConfig)
mergo.MergeWithOverwrite(config, nonMapConfig)
if rules.ResolvePaths() {
if err := ResolveLocalPaths(config); err != nil {
errlist = append(errlist, err)
}
}
return config, utilerrors.NewAggregate(errlist)
}
获取配置文件以及合并配置文件都在同一个方法Load中，其中kubeConfigFiles是记录获取到的配置信息，然后会循环它通过LoadFromFile把配置信息读取出来记录到config对象中，然后通过kubeconfigs将所有的config存起来，然后通过mergo.MergeWithOverwrite将所有的config进行合并。
ClientSet
ClientSet在RESTClient的基础上封装了对Resource和Version的管理方法。每一个Resource可以理解为一个客户端，而ClientSet则是多个客户端的集合，每一个Resource和Version都以函数的方式暴露给开发者。
注意：ClientSet仅能访问Kubernetes自身内置的资源（即客户端集合内的资源），不能直接访问CRD自定义资源。
package main
import (
"fmt"
apiv1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/tools/clientcmd"
)
func main() {
config, err := clientcmd.BuildConfigFromFlags("", "./config")
if err != nil {
panic(err)
}
clientset, err := kubernetes.NewForConfig(config)
if err != nil {
panic(err)
}
podClient := clientset.CoreV1().Pods(apiv1.NamespaceDefault)
podList, err := podClient.List(metav1.ListOptions{Limit: 10})
if err != nil {
panic(err)
}
for _,pod := range podList.Items{
fmt.Printf("NAMESPACE: %v \nNAME: %v \nSTATUS: %v \n",pod.Namespace,pod.Name,pod.Status)
}
}
通过clientcmd.BuildConfigFromFlags来加载配置文件，然后通过kubernetes.NewForConfig来创建clientset对象。然后通过clientset对象来操作集群，比如上面的获取default命名空间下的pod。
简单便捷搭建kubernetes实验环境
做实验时需要有kubernetes集群，传统的kubernetes集群搭建起来比较麻烦，并且一般是一主两从，资源消耗也比较高。面向开发并不需要如此折腾环境，故使用k3s来搭建实验集群，只需要1v2g最基础的主机资源即可。
K3s 是一个轻量级的 Kubernetes 发行版，非常简单易用而且轻量。只需要一个简单的安装脚本即可把 K3s 安装到主机。
使用国内资源安装 K3s
为了解决以上问题，K3s 社区已经将所需的 K3s 资源都同步到了国内的服务器上，这样我们就可以使用这些国内资源在国内环境上安装 K3s，不但提升了安装速度也提升了安装的稳定性。
该站点由 K3s 社区维护，同步资源到国内服务器有可能出现延后或遗漏情况，如发现延后或遗漏情况欢迎反馈到中文论坛(https://forums.rancher.cn)。。)
K3s 社区都同步了哪些资源到国内？
- K3s 安装脚本
- Channel 解析文件
- K3s 的二进制文件
- K3s 依赖系统镜像
使用脚本的安装过程
[root@VM-4-9-centos ~]# curl –sfL \
> https://rancher-mirror.oss-cn-beijing.aliyuncs.com/k3s/k3s-install.sh | \
> INSTALL_K3S_MIRROR=cn sh -s - \
> --system-default-registry "registry.cn-hangzhou.aliyuncs.com"
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0curl: (6) Could not resolve host: xn--sfl-1n0a; 未知的错误
100 29622 100 29622 0 0 37185 0 --:--:-- --:--:-- --:--:-- 37213
[INFO] Finding release for channel stable
[INFO] Using v1.25.4+k3s1 as release
[INFO] Downloading hash rancher-mirror.rancher.cn/k3s/v1.25.4-k3s1/sha256sum-amd64.txt
[INFO] Downloading binary rancher-mirror.rancher.cn/k3s/v1.25.4-k3s1/k3s
[INFO] Verifying binary download
[INFO] Installing k3s to /usr/local/bin/k3s
已加载插件：fastestmirror, langpacks
Loading mirror speeds from cached hostfile
docker | 3.5 kB 00:00:00
docker-ce-stable | 3.5 kB 00:00:00
epel | 4.7 kB 00:00:00
extras | 2.9 kB 00:00:00
os | 3.6 kB 00:00:00
updates | 2.9 kB 00:00:00
(1/6): docker/primary_db | 91 kB 00:00:00
(2/6): epel/7/x86_64/group_gz | 98 kB 00:00:00
(3/6): epel/7/x86_64/updateinfo | 1.0 MB 00:00:00
(4/6): epel/7/x86_64/primary_db | 7.0 MB 00:00:00
(5/6): updates/7/x86_64/primary_db | 19 MB 00:00:01
(6/6): docker-ce-stable/7/x86_64/primary_db | 91 kB 00:00:05
软件包 yum-utils-1.1.31-54.el7_8.noarch 已安装并且是最新版本
无须任何处理
已加载插件：fastestmirror, langpacks
已加载插件：fastestmirror, langpacks
Loading mirror speeds from cached hostfile
rancher-k3s-common-stable | 2.9 kB 00:00:00
rancher-k3s-common-stable/primary_db | 3.8 kB 00:00:00
正在解决依赖关系
There are unfinished transactions remaining. You might consider running yum-complete-transaction, or "yum-complete-transaction --cleanup-only" and "yum history redo last", first to finish them. If those don't work you'll have to try removing/installing packages by hand (maybe package-cleanup can help).
--> 正在检查事务
---> 软件包 k3s-selinux.noarch.0.1.2-2.el7 将被 安装
--> 解决依赖关系完成
依赖关系解决
================================================================================================================================================================================================
Package 架构 版本 源 大小
================================================================================================================================================================================================
正在安装:
k3s-selinux noarch 1.2-2.el7 rancher-k3s-common-stable 16 k
事务概要
================================================================================================================================================================================================
安装 1 软件包
总下载量：16 k
安装大小：94 k
Downloading packages:
警告：/var/cache/yum/x86_64/7/rancher-k3s-common-stable/packages/k3s-selinux-1.2-2.el7.noarch.rpm: 头V3 RSA/SHA256 Signature, 密钥 ID e257814a: NOKEY ] 0.0 B/s | 0 B --:--:-- ETA
k3s-selinux-1.2-2.el7.noarch.rpm 的公钥尚未安装
k3s-selinux-1.2-2.el7.noarch.rpm | 16 kB 00:00:00
从 https://rpm.rancher.io/public.key 检索密钥
导入 GPG key 0xE257814A:
用户ID : "Rancher (CI) <ci@rancher.com>"
指纹 : c8cf f216 4551 26e9 b9c9 18be 925e a29a e257 814a
来自 : https://rpm.rancher.io/public.key
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
正在安装 : k3s-selinux-1.2-2.el7.noarch 1/1
验证中 : k3s-selinux-1.2-2.el7.noarch 1/1
已安装:
k3s-selinux.noarch 0:1.2-2.el7
完毕！
[INFO] Creating /usr/local/bin/kubectl symlink to k3s
[INFO] Creating /usr/local/bin/crictl symlink to k3s
[INFO] Skipping /usr/local/bin/ctr symlink to k3s, command exists in PATH at /usr/bin/ctr
[INFO] Creating killall script /usr/local/bin/k3s-killall.sh
[INFO] Creating uninstall script /usr/local/bin/k3s-uninstall.sh
[INFO] env: Creating environment file /etc/systemd/system/k3s.service.env
[INFO] systemd: Creating service file /etc/systemd/system/k3s.service
[INFO] systemd: Enabling k3s unit
Created symlink from /etc/systemd/system/multi-user.target.wants/k3s.service to /etc/systemd/system/k3s.service.
[INFO] systemd: Starting k3s
[root@VM-4-9-centos ~]# systemctl status k3s
● k3s.service - Lightweight Kubernetes
Loaded: loaded (/etc/systemd/system/k3s.service; enabled; vendor preset: disabled)
Active: active (running) since 五 2023-01-13 12:46:12 CST; 24s ago
Docs: https://k3s.io
Process: 6473 ExecStartPre=/sbin/modprobe overlay (code=exited, status=0/SUCCESS)
Process: 6454 ExecStartPre=/sbin/modprobe br_netfilter (code=exited, status=0/SUCCESS)
Process: 6451 ExecStartPre=/bin/sh -xc ! /usr/bin/systemctl is-enabled --quiet nm-cloud-setup.service (code=exited, status=0/SUCCESS)
Main PID: 6476 (k3s-server)
Tasks: 105
Memory: 884.4M
CGroup: /system.slice/k3s.service
├─6476 /usr/local/bin/k3s server
├─6587 containerd -c /var/lib/rancher/k3s/agent/etc/containerd/config.toml -a /run/k3s/containerd/containerd.sock --state /run/k3s/containerd --root /var/lib/rancher/k3s/agent/co...
├─7601 /var/lib/rancher/k3s/data/7c994f47fd344e1637da337b92c51433c255b387d207b30b3e0262779457afe4/bin/containerd-shim-runc-v2 -namespace k8s.io -id e80172081d95e02dcc5e5b9ad14403...
├─7705 /var/lib/rancher/k3s/data/7c994f47fd344e1637da337b92c51433c255b387d207b30b3e0262779457afe4/bin/containerd-shim-runc-v2 -namespace k8s.io -id 313b2efd8f921f314c1719ce2496d8...
├─7773 /var/lib/rancher/k3s/data/7c994f47fd344e1637da337b92c51433c255b387d207b30b3e0262779457afe4/bin/containerd-shim-runc-v2 -namespace k8s.io -id 8eadb368dded3bc0184d7d25e251fb...
├─7799 /var/lib/rancher/k3s/data/7c994f47fd344e1637da337b92c51433c255b387d207b30b3e0262779457afe4/bin/containerd-shim-runc-v2 -namespace k8s.io -id 12d9f5d7f6a162045a645e3825d47e...
├─7800 /var/lib/rancher/k3s/data/7c994f47fd344e1637da337b92c51433c255b387d207b30b3e0262779457afe4/bin/containerd-shim-runc-v2 -namespace k8s.io -id 737ead2c0fbb4a8627968814437a49...
└─8429 /var/lib/rancher/k3s/data/7c994f47fd344e1637da337b92c51433c255b387d207b30b3e0262779457afe4/bin/unpigz -d -c
1月 13 12:46:27 VM-4-9-centos k3s[6476]: E0113 12:46:27.794864 6476 controller.go:113] loading OpenAPI spec for "v1beta1.metrics.k8s.io" failed with: Error, could not get li...r APIService
1月 13 12:46:27 VM-4-9-centos k3s[6476]: I0113 12:46:27.794875 6476 controller.go:126] OpenAPI AggregationController: action for item v1beta1.metrics.k8s.io: Rate Limited Requeue.
1月 13 12:46:27 VM-4-9-centos k3s[6476]: W0113 12:46:27.795895 6476 handler_proxy.go:105] no RequestInfo found in the context
1月 13 12:46:27 VM-4-9-centos k3s[6476]: E0113 12:46:27.795984 6476 controller.go:116] loading OpenAPI spec for "v1beta1.metrics.k8s.io" failed with: failed to retrieve open... unavailable
1月 13 12:46:27 VM-4-9-centos k3s[6476]: , Header: map[Content-Type:[text/plain; charset=utf-8] X-Content-Type-Options:[nosniff]]
1月 13 12:46:27 VM-4-9-centos k3s[6476]: I0113 12:46:27.795999 6476 controller.go:129] OpenAPI AggregationController: action for item v1beta1.metrics.k8s.io: Rate Limited Requeue.
1月 13 12:46:39 VM-4-9-centos k3s[6476]: I0113 12:46:39.280428 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik-crd
1月 13 12:46:39 VM-4-9-centos k3s[6476]: I0113 12:46:39.357202 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik
1月 13 12:46:40 VM-4-9-centos k3s[6476]: I0113 12:46:40.484801 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik
1月 13 12:46:40 VM-4-9-centos k3s[6476]: I0113 12:46:40.547706 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik-crd
1月 13 12:46:42 VM-4-9-centos k3s[6476]: I0113 12:46:42.091825 6476 scope.go:115] "RemoveContainer" containerID="9b5c8ddbad63bd2a65749bde4aa6c07edc80466276f9487a421c973ad34a4998"
1月 13 12:46:42 VM-4-9-centos k3s[6476]: I0113 12:46:42.248162 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.385377 6476 trace.go:205] Trace[1639472897]: "Create" url:/api/v1/namespaces/kube-system/secrets,user-agent:Go-http-client/2.0,au...
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1639472897]: ---"Write to database call finished" len:78320,err:<nil> 687ms (12:46:43.384)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1639472897]: [689.967749ms] [689.967749ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.668908 6476 trace.go:205] Trace[459355219]: "GuaranteedUpdate etcd3" audit-id:83646a7c-8cae-4cbd-9e97-4c2c83b375e1,ke...ime: 596ms):
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[459355219]: ---"Txn call finished" err:<nil> 593ms (12:46:43.668)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[459355219]: [596.747443ms] [596.747443ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.670046 6476 trace.go:205] Trace[1616843808]: "Patch" url:/api/v1/namespaces/kube-system/pods/helm-install-traefik-kxcp9/status,us...
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1616843808]: ---"Object stored in database" 594ms (12:46:43.668)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1616843808]: [598.010992ms] [598.010992ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.672647 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.757924 6476 trace.go:205] Trace[727563776]: "GuaranteedUpdate etcd3" audit-id:e0d61d36-e7c7-4118-8747-cd1ec82e6835,ke...ime: 504ms):
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[727563776]: ---"Txn call finished" err:<nil> 501ms (12:46:43.757)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[727563776]: [504.20138ms] [504.20138ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.759312 6476 trace.go:205] Trace[1270597021]: "GuaranteedUpdate etcd3" audit-id:04ff8cec-5cab-464f-a380-3f41ea7cc532,k...ime: 509ms):
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1270597021]: ---"Txn call finished" err:<nil> 506ms (12:46:43.759)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1270597021]: [509.049327ms] [509.049327ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.759637 6476 trace.go:205] Trace[453658084]: "Patch" url:/api/v1/nodes/vm-4-9-centos/status,user-agent:k3s/v1.25.4+k3s1 (linux/amd...
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[453658084]: ---"Object stored in database" 502ms (12:46:43.757)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[453658084]: [547.022256ms] [547.022256ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.759861 6476 trace.go:205] Trace[1652397100]: "Update" url:/apis/batch/v1/namespaces/kube-system/jobs/helm-install-traefik/status,...
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1652397100]: ---"Write to database call finished" len:5074,err:<nil> 509ms (12:46:43.759)
1月 13 12:46:43 VM-4-9-centos k3s[6476]: Trace[1652397100]: [510.076026ms] [510.076026ms] END
1月 13 12:46:43 VM-4-9-centos k3s[6476]: I0113 12:46:43.812298 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik
1月 13 12:46:44 VM-4-9-centos k3s[6476]: I0113 12:46:44.032551 6476 job_controller.go:510] enqueueing job kube-system/helm-install-traefik
Hint: Some lines were ellipsized, use -l to show in full.
检查安装结果
节点正常
[root@VM-4-9-centos ~]# kubectl get nodes -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
vm-4-9-centos Ready control-plane,master 14d v1.25.4+k3s1 10.0.4.9 <none> CentOS Linux 7 (Core) 3.10.0-1160.71.1.el7.x86_64 containerd://1.6.8-k3s1
命名空间正常
[root@VM-4-9-centos ~]# kubectl get ns -o wide -A
NAME STATUS AGE
kube-system Active 14d
default Active 14d
kube-public Active 14d
kube-node-lease Active 14d
初始的pod 正常
[root@VM-4-9-centos ~]# kubectl get pods -o wide -A
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-system coredns-fd7f5dc55-74d5d 1/1 Running 0 14d 10.42.0.4 vm-4-9-centos <none> <none>
kube-system local-path-provisioner-66b5f84849-7lgxx 1/1 Running 0 14d 10.42.0.6 vm-4-9-centos <none> <none>
kube-system helm-install-traefik-crd-cb859 0/1 Completed 0 14d 10.42.0.3 vm-4-9-centos <none> <none>
kube-system helm-install-traefik-kxcp9 0/1 Completed 1 14d 10.42.0.2 vm-4-9-centos <none> <none>
kube-system svclb-traefik-0c07dca9-f7w8j 2/2 Running 0 14d 10.42.0.7 vm-4-9-centos <none> <none>
kube-system metrics-server-b4bb65577-jwklq 1/1 Running 0 14d 10.42.0.5 vm-4-9-centos <none> <none>
kube-system traefik-7db84f77c9-vgbzk 1/1 Running 0 14d 10.42.0.8 vm-4-9-centos <none> <none>
测试集群的远程连接
本地配置kube config文件
k3s集群的config文件在如下位置
[root@VM-4-9-centos ~]# ll /etc/rancher/k3s/k3s.yaml
-rw------- 1 root root 2969 1月 13 12:46 /etc/rancher/k3s/k3s.yaml
将k3s.yaml下载下来，将文件中server: https://127.0.0.1:6443的地址改成可以访问的地址，注意网络要通。
放置在用户目录下，重命名为config，非必须这么做，反正到时候能读到该文件即可
测试连接k3s集群
provider/k8s/client.go
构造集群客户端结构体，实现client-go的一些基本方法
var (
DEFAULT_NAMESPACE = "default"
)
func NewClient(kubeConfigYaml string) (*Client, error) {
// 加载kubeconfig配置
kubeConf, err := clientcmd.Load([]byte(kubeConfigYaml))
if err != nil {
return nil, err
}
// 构造Restclient Config
restConf, err := clientcmd.BuildConfigFromKubeconfigGetter("",
func() (*clientcmdapi.Config, error) {
return kubeConf, nil
},
)
if err != nil {
return nil, err
}
// 初始化客户端
client, err := kubernetes.NewForConfig(restConf)
if err != nil {
return nil, err
}
// 基于Interface封装的客户端
// client.AppsV1().Deployments("default").Create(nil, nil, metav1.CreateOptions{})
// RESTclient https://github.com/jindezgm/k8s-src-analysis/blob/master/client-go/rest/Client.md
// client.RESTClient().Post().Namespace("ns").Body("body").Do(nil).Into(resp).Error()
return &Client{
kubeconf: kubeConf,
restconf: restConf,
client: client,
log: zap.L().Named("provider.k8s"),
}, nil
}
type Client struct {
kubeconf *clientcmdapi.Config
restconf *rest.Config
client *kubernetes.Clientset
log logger.Logger
}
func (c *Client) ServerVersion() (string, error) {
si, err := c.client.ServerVersion()
if err != nil {
return "", err
}
return si.String(), nil
}
provider/k8s/client_test.go
测试连接集群，打印集群版本
//加载依赖
func init() {
zap.DevelopmentSetup()
// 获取当前文件在哪个目录下
//wd, err := os.Getwd()
//fmt.Println(wd)
//if err != nil {
// panic(err)
//}
kc, err := os.ReadFile(filepath.Join("C:\\Users\\zengz\\.kube", "config"))
if err != nil {
panic(err)
}
client, err = k8s.NewClient(string(kc))
if err != nil {
panic(err)
}
}
var (
client *k8s.Client
ctx = context.Background()
)
func TestServerVersion(t *testing.T) {
v, err := client.ServerVersion()
if err != nil {
t.Fatal(err)
}
t.Log(v)
}
测试通过，连接集群成功
=== RUN TestServerVersion
client_test.go:30: v1.25.4+k3s1
--- PASS: TestServerVersion (0.03s)
PASS
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