k8s源码设计模式之Template Method

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模板方法是一种行为设计模式，用于定义一个操作的算法骨架，而将一些步骤的实现推迟到子类中。它可以使子类在不改变算法结构的情况下重定义算法中的某些步骤。

k8s源码中client-go中模版方法

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// staging/src/k8s.io/client-go/rest/client.go
type Interface interface {
	GetRateLimiter() flowcontrol.RateLimiter
	Verb(verb string) *Request
	Post() *Request
	Put() *Request
	Patch(pt types.PatchType) *Request
	Get() *Request
	Delete() *Request
	APIVersion() schema.GroupVersion
}

// RESTClient实现了Interface
type RESTClient struct {
	// base is the root URL for all invocations of the client
	base *url.URL
	// versionedAPIPath is a path segment connecting the base URL to the resource root
	versionedAPIPath string

	// content describes how a RESTClient encodes and decodes responses.
	content ClientContentConfig

	// creates BackoffManager that is passed to requests.
	createBackoffMgr func() BackoffManager

	// rateLimiter is shared among all requests created by this client unless specifically
	// overridden.
	rateLimiter flowcontrol.RateLimiter

	// warningHandler is shared among all requests created by this client.
	// If not set, defaultWarningHandler is used.
	warningHandler WarningHandler

	// Set specific behavior of the client.  If not set http.DefaultClient will be used.
	Client *http.Client
}
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// staging/src/k8s.io/client-go/dynamic/simple.go
type DynamicClient struct {
	client rest.Interface
}

// dynamicResourceClient对需要重写的方法进行了重写
type dynamicResourceClient struct {
	client    *DynamicClient
	namespace string
	resource  schema.GroupVersionResource
}

REF:
1.staging/src/k8s.io/client-go/rest/client.go
2.staging/src/k8s.io/client-go/dynamic/simple.go