环境准备
go环境配置
wget https://golang.google.cn/dl/go1.19.8.linux-amd64.tar.gz
tar zxvf go1.19.8.linux-amd64.tar.gz
mv go /usr/local/
vim /etc/profile在最结尾添加
export HOME=/root
export GOROOT=/usr/local/go
export GOPATH=/opt/idcus/go
export PATH=$PATH:$GOPATH/bin:$GOROOT/bin
source /etc/profile
go version #查看是否生效
配置kubebuilder
# 下载最新版本的kubebuilder
curl -L -o kubebuilder https://go.kubebuilder.io/dl/latest/$(go env GOOS)/$(go env GOARCH)
# 本次使用的v3.9.1会出现报错bug,所以使用v3.8.0
wget https://github.com/kubernetes-sigs/kubebuilder/releases/download/v3.8.0/kubebuilder_linux_amd64
chmod +x kubebuilder && mv kubebuilder /usr/local/bin/
验证版本
[root@test ~]# kubebuilder version
Version: main.version{KubeBuilderVersion:"3.8.0", KubernetesVendor:"1.25.0", GitCommit:"184ff7465947ced153b031db8de297a778cecf36", BuildDate:"2022-12-04T18:17:10Z", GoOs:"linux", GoArch:"amd64"}
创建k8s-host.yaml
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
name: host
nodes:
- role: control-plane
image: kindest/node:v1.21.14@sha256:9d9eb5fb26b4fbc0c6d95fa8c790414f9750dd583f5d7cee45d92e8c26670aa1
- role: worker
image: kindest/node:v1.21.14@sha256:9d9eb5fb26b4fbc0c6d95fa8c790414f9750dd583f5d7cee45d92e8c26670aa1
- role: worker
image: kindest/node:v1.21.14@sha256:9d9eb5fb26b4fbc0c6d95fa8c790414f9750dd583f5d7cee45d92e8c26670aa1
networking:
apiServerAddress: "127.0.0.1"
apiServerPort: 6443
使用kind创建一个k8s集群
kind create cluster --config k8s-host.yaml
验证集群
[root@test ~]# kubectl get no
NAME STATUS ROLES AGE VERSION
host-control-plane Ready control-plane,master 12d v1.21.14
host-worker Ready <none> 12d v1.21.14
host-worker2 Ready <none> 12d v1.21.14
初始化项目
mkdir application-operator
cd application-operator
go mod init application-operator
kubebuilder init --domain=qwbyx.com --owner qwbyx
kubebuilder create api --group apps --version v1 --kind Application
CRD实现和部署
使用goland远程ssh模式进行开发
将api/v1/application_types.go
中修改以下部分
import (
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)
// EDIT THIS FILE! THIS IS SCAFFOLDING FOR YOU TO OWN!
// NOTE: json tags are required. Any new fields you add must have json tags for the fields to be serialized.
// ApplicationSpec defines the desired state of Application
type ApplicationSpec struct {
// INSERT ADDITIONAL SPEC FIELDS - desired state of cluster
// Important: Run "make" to regenerate code after modifying this file
// Foo is an example field of Application. Edit application_types.go to remove/update
//Foo string `json:"foo,omitempty"`
Replicas int32 `json:"replicas,omitempty"`
Template corev1.PodTemplateSpec `json:"template,omitempty"`
}
CRD部署
make install
验证
[root@test ~]# kubectl get crd
NAME CREATED AT
applications.apps.qwbyx.com 2023-04-14T09:15:49Z
CR部署
将config/samples/apps_v1_application.yaml改为如下
apiVersion: apps.qwbyx.com/v1
kind: Application
metadata:
name: application-sample
namespace: default
labels:
app: nginx
# labels:
# app.kubernetes.io/name: application
# app.kubernetes.io/instance: application-sample
# app.kubernetes.io/part-of: application-operator
# app.kubernetes.io/managed-by: kustomize
# app.kubernetes.io/created-by: application-operator
# name: application-sample
spec:
replicas: 3
template:
spec:
containers:
- name: nginx
image: nginx:1.14.2
ports:
- containerPort: 80
进行部署
[root@test application-operator]# kubectl apply -f config/samples/apps_v1_application.yaml
application.apps.qwbyx.com/application-sample created
查询
[root@test ~]# kubectl get application
NAME AGE
application-sample 3s
Controller的实现和部署
修改controllers/application_controller.go内容如下
package controllers
import (
"context"
"fmt"
corev1 "k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"time"
"k8s.io/apimachinery/pkg/runtime"
ctrl "sigs.k8s.io/controller-runtime"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/log"
dappsv1 "application-operator/api/v1"
)
// ApplicationReconciler reconciles a Application object
type ApplicationReconciler struct {
client.Client
Scheme *runtime.Scheme
}
//+kubebuilder:rbac:groups=apps.qwbyx.com,resources=applications,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=apps.qwbyx.com,resources=applications/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=apps.qwbyx.com,resources=applications/finalizers,verbs=update
// Reconcile is part of the main kubernetes reconciliation loop which aims to
// move the current state of the cluster closer to the desired state.
// TODO(user): Modify the Reconcile function to compare the state specified by
// the Application object against the actual cluster state, and then
// perform operations to make the cluster state reflect the state specified by
// the user.
//
// For more details, check Reconcile and its Result here:
// - https://pkg.go.dev/sigs.k8s.io/[email protected]/pkg/reconcile
func (r *ApplicationReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
l := log.FromContext(ctx)
// get the Application
app := &dappsv1.Application{}
if err := r.Get(ctx, req.NamespacedName, app); err != nil {
if errors.IsNotFound(err) {
l.Info("the Application is not found")
return ctrl.Result{}, nil
}
l.Error(err, "failed to get the Application")
return ctrl.Result{RequeueAfter: 1 * time.Minute}, err
}
// create pods
for i := 0; i < int(app.Spec.Replicas); i++ {
pod := &corev1.Pod{
ObjectMeta: metav1.ObjectMeta{
Name: fmt.Sprintf("%s-%d", app.Name, i),
Namespace: app.Namespace,
Labels: app.Labels,
},
Spec: app.Spec.Template.Spec,
}
if err := r.Create(ctx, pod); err != nil {
l.Error(err, "failed to create Pod")
return ctrl.Result{RequeueAfter: 1 * time.Minute}, err
}
l.Info(fmt.Sprintf("the Pod (%s) has created", pod.Name))
}
l.Info("all pods has created")
return ctrl.Result{}, nil
}
// SetupWithManager sets up the controller with the Manager.
func (r *ApplicationReconciler) SetupWithManager(mgr ctrl.Manager) error {
return ctrl.NewControllerManagedBy(mgr).
For(&dappsv1.Application{}).
Complete(r)
}
启动controller
make run
查询
[root@test ~]# kubectl get po
NAME READY STATUS RESTARTS AGE
application-sample-0 1/1 Running 0 23h
application-sample-1 1/1 Running 0 23h
application-sample-2 1/1 Running 0 23h
以容器形式部署controller
在Dockerfile第三行添加如下
ENV GOPROXY=https://goproxy.io
准备镜像
docker pull kubeimages/distroless-static
docker tag kubeimages/distroless-static:latest gcr.io/distroless/static:nonroot
docker pull quay.io/brancz/kube-rbac-proxy:v0.13.1
docker tag quay.io/brancz/kube-rbac-proxy:v0.13.1 gcr.io/kubebuilder/kube-rbac-proxy:v0.13.1
将镜像注入k8s集群
make docker-build IMG=application-operator:v0.0.1
kind load docker-image application-operator:v0.0.1 --name host
kind load docker-image gcr.io/kubebuilder/kube-rbac-proxy:v0.13.1 --name host
部署
make deploy IMG=application-operator:v0.0.1
查询
[root@test ~]# kubectl get po -n application-operator-system
NAME READY STATUS RESTARTS AGE
application-operator-controller-manager-c97f78f45-457s7 2/2 Running 0 28m
资源清理
卸载controller
make undeploy
卸载CRD
make uninstall
标签:demo,application,kubebuilder,io,operator,k8s,go
From: https://www.cnblogs.com/ltaodream/p/17323814.html