├── code-gen.sh
├── controller.go
├── crd
│ └── mydemo.yaml
├── example
│ └── example-mydemo.yaml
├── go.mod
├── go.sum
├── main.go
└── pkg
└── apis
└── crddemo
├── register.go
└── v1
├── doc.go
├── register.go
├── types.gosh code-gen.sh
执行后，会在crddemo/pkg目录生成对应的代码
client
├── clientset
│ └── versioned
│ ├── clientset.go
│ ├── doc.go
│ ├── fake
│ │ ├── clientset_generated.go
│ │ ├── doc.go
│ │ └── register.go
│ ├── scheme
│ │ ├── doc.go
│ │ └── register.go
│ └── typed
│ └── crddemo
│ └── v1
│ ├── crddemo_client.go
│ ├── doc.go
│ ├── fake
│ │ ├── doc.go
│ │ ├── fake_crddemo_client.go
│ │ └── fake_mydemo.go
│ ├── generated_expansion.go
│ └── mydemo.go
├── informers
│ └── externalversions
│ ├── crddemo
│ │ ├── interface.go
│ │ └── v1
│ │ ├── interface.go
│ │ └── mydemo.go
│ ├── factory.go
│ ├── generic.go
│ └── internalinterfaces
│ └── factory_interfaces.go
└── listers
└── crddemo
└── v1
├── expansion_generated.go
└── mydemo.go$ make
... ...
gofmt -w .
go test -v .
? github.com/domac/crddemo [no test files]
mkdir -p releases
GOOS=linux GOARCH=amd64 go build -mod=vendor -ldflags "-s -w" -v -o releases/crddemo *.go
github.com/golang/groupcache/lru
k8s.io/apimachinery/third_party/forked/golang/json
k8s.io/apimachinery/pkg/util/mergepatch
k8s.io/kube-openapi/pkg/util/proto
k8s.io/client-go/tools/record/util
k8s.io/apimachinery/pkg/util/strategicpatch
k8s.io/client-go/tools/record
command-line-arguments
go clean -i
... ...把crddemo放到kubernetes集群中，或者本地也行，只要能访问到apiserver和具备kubeconfig
可以看到，程序运行的时候，一开始会报错。这是因为，此时 Mydemo 对象的 CRD 还没有被创建出来，所以 Informer 去 APIServer 里获取 Mydemos 对象时，并不能找到 Mydemo 这个 API 资源类型的定义
$ ./crddemo --kubeconfig=/data/svr/projects/kubernetes/config/kubectl.kubeconfig --master=http://127.0.0.1:8080 -alsologtostderr=true
I0308 12:23:18.494507 27426 controller.go:79] Setting up mydemo event handlers
I0308 12:23:18.494829 27426 controller.go:105] Starting Mydemo control loop
I0308 12:23:18.494840 27426 controller.go:108] Waiting for informer caches to sync
E0308 12:23:18.496902 27426 reflector.go:178] github.com/domac/crddemo/pkg/client/informers/externalversions/factory.go:117: Failed to list *v1.Mydemo: the server could not find the requested resource (get mydemos.crddemo.k8s.io)
E0308 12:23:18.497477 27426 reflector.go:178] github.com/domac/crddemo/pkg/client/informers/externalversions/factory.go:117: Failed to list *v1.Mydemo: the server could not find the requested resource (get mydemos.crddemo.k8s.io)
E0308 12:23:21.604508 27426 reflector.go:178] github.com/domac/crddemo/pkg/client/informers/externalversions/factory.go:117: Failed to list *v1.Mydemo: the server could not find the requested resource (get mydemos.crddemo.k8s.io)
E0308 12:23:26.932293 27426 reflector.go:178] github.com/domac/crddemo/pkg/client/informers/externalversions/factory.go:117: Failed to list *v1.Mydemo: the server could not find the requested resource (get mydemos.crddemo.k8s.io)
... ...
接下来，我们执行我们自定义资源的定义文件：
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: mydemos.crddemo.k8s.io
spec:
group: crddemo.k8s.io
version: v1
names:
kind: Mydemo
plural: mydemos
scope: Namespaced执行创建
$ kubectl apply -f crd/mydemo.yaml
customresourcedefinition.apiextensions.k8s.io/mydemos.crddemo.k8s.io created
此时，观察crddemo的日志输出，可以看到Controller的日志恢复了正常，控制循环启动成功
I0308 12:30:29.956263 28282 controller.go:113] Starting workers
I0308 12:30:29.956307 28282 controller.go:118] Started workers
然后，我们可以对我们的Mydemo对象进行增删改查操作了。
首先，新建一个自定义资源对象
example-mydemo.yaml
apiVersion: crddemo.k8s.io/v1
kind: Mydemo
metadata:
name: example-mydemo
spec:
ip: "127.0.0.1"
port: 8080执行创建
$ kubectl apply -f example-mydemo.yaml
mydemo.crddemo.k8s.io/example-mydemo created
创建成功够，看k8s集群是否成功存储起来
$ kubectl get Mydemo
NAME AGE
example-mydemo 2s
这时候，查看一下控制器的输出：
I0308 12:31:24.983663 28282 controller.go:216] [DemoCRD] Try to process mydemo: &v1.Mydemo{TypeMeta:v1.TypeMeta{Kind:"", APIVersion:""}, ObjectMeta:v1.ObjectMeta{Name:"example-mydemo", GenerateName:"", Namespace:"default", SelfLink:"/apis/crddemo.k8s.io/v1/namespaces/default/mydemos/example-mydemo", UID:"8a6d17f7-17f3-4a1d-8250-bb092678ae7e", ResourceVersion:"10818363", Generation:1, CreationTimestamp:v1.Time{Time:time.Time{wall:0x0, ext:63719238684, loc:(*time.Location)(0x1e566c0)}}, DeletionTimestamp:(*v1.Time)(nil), DeletionGracePeriodSeconds:(*int64)(nil), Labels:map[string]string(nil), Annotations:map[string]string{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"crddemo.k8s.io/v1\",\"kind\":\"Mydemo\",\"metadata\":{\"annotations\":{},\"name\":\"example-mydemo\",\"namespace\":\"default\"},\"spec\":{\"ip\":\"127.0.0.1\",\"port\":8080}}\n"}, OwnerReferences:[]v1.OwnerReference(nil), Finalizers:[]string(nil), ClusterName:"", ManagedFields:[]v1.ManagedFieldsEntry(nil)}, Spec:v1.MydemoSpec{Ip:"127.0.0.1", Port:8080}} ...
I0308 12:31:24.983844 28282 controller.go:174] Successfully synced 'default/example-mydemo'
I0308 12:31:24.983893 28282 event.go:278] Event(v1.ObjectReference{Kind:"Mydemo", Namespace:"default", Name:"example-mydemo", UID:"8a6d17f7-17f3-4a1d-8250-bb092678ae7e", APIVersion:"crddemo.k8s.io/v1", ResourceVersion:"10818363", FieldPath:""}): type: 'Normal' reason: 'Synced' Mydemo synced successfully
可以看到，我们上面创建 example-mydemo.yaml 的操作，触发了 EventHandler 的添加事件，从而被放进了工作队列。紧接着，控制循环就从队列里拿到了这个对象，并且打印出了正在处理这个 Mydemo 对象的日志。
我们这时候，尝试修改资源，对对应的port属性进行修改
apiVersion: crddemo.k8s.io/v1
kind: Mydemo
metadata:
name: example-mydemo
spec:
ip: "127.0.0.1"
port: 9090手段执行修改
$ kubectl apply -f example-mydemo.yaml
此时，crddemo新增出来的日志如下：
I0308 12:32:05.663044 28282 controller.go:216] [DemoCRD] Try to process mydemo: &v1.Mydemo{TypeMeta:v1.TypeMeta{Kind:"", APIVersion:""}, ObjectMeta:v1.ObjectMeta{Name:"example-mydemo", GenerateName:"", Namespace:"default", SelfLink:"/apis/crddemo.k8s.io/v1/namespaces/default/mydemos/example-mydemo", UID:"8a6d17f7-17f3-4a1d-8250-bb092678ae7e", ResourceVersion:"10818457", Generation:2, CreationTimestamp:v1.Time{Time:time.Time{wall:0x0, ext:63719238684, loc:(*time.Location)(0x1e566c0)}}, DeletionTimestamp:(*v1.Time)(nil), DeletionGracePeriodSeconds:(*int64)(nil), Labels:map[string]string(nil), Annotations:map[string]string{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"crddemo.k8s.io/v1\",\"kind\":\"Mydemo\",\"metadata\":{\"annotations\":{},\"name\":\"example-mydemo\",\"namespace\":\"default\"},\"spec\":{\"ip\":\"127.0.0.1\",\"port\":9080}}\n"}, OwnerReferences:[]v1.OwnerReference(nil), Finalizers:[]string(nil), ClusterName:"", ManagedFields:[]v1.ManagedFieldsEntry(nil)}, Spec:v1.MydemoSpec{Ip:"127.0.0.1", Port:9080}} ...
I0308 12:32:05.663179 28282 controller.go:174] Successfully synced 'default/example-mydemo'
I0308 12:32:05.663208 28282 event.go:278] Event(v1.ObjectReference{Kind:"Mydemo", Namespace:"default", Name:"example-mydemo", UID:"8a6d17f7-17f3-4a1d-8250-bb092678ae7e", APIVersion:"crddemo.k8s.io/v1", ResourceVersion:"10818457", FieldPath:""}): type: 'Normal' reason: 'Synced' Mydemo synced successfully
可以看到，这一次，Informer 注册的“更新”事件被触发，更新后的 Mydemo 对象的 Key 被添加到了工作队列之中。
所以，接下来控制循环从工作队列里拿到的 Mydemo 对象，与前一个对象是不同的：它的 ResourceVersion 的值从 10818363 变成了 10818457 ；而 Spec 里的Port字段，则变成了 9080。最后，我再把这个对象删除掉：
$ kubectl delete -f example-mydemo.yaml
mydemo.crddemo.k8s.io "example-mydemo" deleted
这一次，在控制器的输出里，我们就可以看到，Informer 注册的“删除”事件被触发,输出如下：
W0308 12:33:08.494755 28282 controller.go:203] DemoCRD: default/example-mydemo does not exist in local cache, will delete it from Mydemo ...
I0308 12:33:08.495793 28282 controller.go:206] [DemoCRD] Deleting mydemo: default/example-mydemo ...
I0308 12:33:08.495808 28282 controller.go:174] Successfully synced 'default/example-mydemo'
然后，k8s集群的资源也被清除了：
$ kubectl get Mydemo
No resources found in default namespace.
以上就是使用自定义控制器的基本开发流程