配置項(xiàng)定義

文件/kube-apiserver/app/options/options.go

• func (s *ServerRunOptions) Flags() (fss cliflag.NamedFlagSets)

# 配置詳解后續(xù)根據(jù)需要逐步補(bǔ)充,基本配置都在options包里,再使用options包的過程中,首先生成雜亂的配置全量跟默認(rèn)配置,然后再對(duì)這些雜亂的配置進(jìn)行歸類

server啟動(dòng)過程

文件cmd/kube-apiserver/app/server.go

這里創(chuàng)建了比較重要的api handler CreateKubeAPIServer后文詳解

• func Run(completeOptions completedServerRunOptions, stopCh <-chan struct{}) error

func Run(completeOptions completedServerRunOptions, stopCh <-chan struct{}) error {
    // To help debugging, immediately log version
    klog.Infof("Version: %+v", version.Get())
    // 這里初始化了server的啟動(dòng)配置,裝載了一些攔截器,合并配置跟api handler擴(kuò)展,最終返回一個(gè)aggregatorapiserver.APIAggregator對(duì)象.
    server, err := CreateServerChain(completeOptions, stopCh)
    if err != nil {
        return err
    }
    // 裝在一些健康檢查handler,初始化路由,審計(jì)backend
    prepared, err := server.PrepareRun()
    if err != nil {
        return err
    }

    return prepared.Run(stopCh)
}

文件vendor/k8s.io/apiserver/pkg/server/genericapiserver.go

最終執(zhí)行的http server的運(yùn)行,這里定義了如何優(yōu)雅退出邏輯

• func (s preparedGenericAPIServer) Run(stopCh <-chan struct{}) error

kubeAPIServer創(chuàng)建流程

文件pkg/controlplane/instance.go

這里為整個(gè)創(chuàng)建流程

• func (c completedConfig) New(delegationTarget genericapiserver.DelegationTarget) (*Instance, error)

func (c completedConfig) New(delegationTarget genericapiserver.DelegationTarget) (*Instance, error) {
    // 這里創(chuàng)建GenericAPIServer在下面展開說
    s, err := c.GenericConfig.New("kube-apiserver", delegationTarget)
    if err != nil {
        return nil, err
    }
    ...
    // 這里生成最終返回的instance下面展開說
    m := &Instance{
        GenericAPIServer:          s,
        ClusterAuthenticationInfo: c.ExtraConfig.ClusterAuthenticationInfo,
    }
    ...
    restStorageProviders := []RESTStorageProvider{
        apiserverinternalrest.StorageProvider{},
        authenticationrest.RESTStorageProvider{Authenticator: c.GenericConfig.Authentication.Authenticator, APIAudiences: c.GenericConfig.Authentication.APIAudiences},
        authorizationrest.RESTStorageProvider{Authorizer: c.GenericConfig.Authorization.Authorizer, RuleResolver: c.GenericConfig.RuleResolver},
        autoscalingrest.RESTStorageProvider{},
        batchrest.RESTStorageProvider{},
        certificatesrest.RESTStorageProvider{},
        coordinationrest.RESTStorageProvider{},
        discoveryrest.StorageProvider{},
        networkingrest.RESTStorageProvider{},
        noderest.RESTStorageProvider{},
        policyrest.RESTStorageProvider{},
        rbacrest.RESTStorageProvider{Authorizer: c.GenericConfig.Authorization.Authorizer},
        schedulingrest.RESTStorageProvider{},
        storagerest.RESTStorageProvider{},
        flowcontrolrest.RESTStorageProvider{},
        // keep apps after extensions so legacy clients resolve the extensions versions of shared resource names.
        // See https://github.com/kubernetes/kubernetes/issues/42392
        appsrest.StorageProvider{},
        admissionregistrationrest.RESTStorageProvider{},
        eventsrest.RESTStorageProvider{TTL: c.ExtraConfig.EventTTL},
    }
    // 裝載api
    if err := m.InstallAPIs(c.ExtraConfig.APIResourceConfigSource, c.GenericConfig.RESTOptionsGetter, restStorageProviders...); err != nil {
        return nil, err
    }


    

    return m, nil
}

• func (m *Instance) InstallAPIs(apiResourceConfigSource serverstorage.APIResourceConfigSource, restOptionsGetter generic.RESTOptionsGetter, restStorageProviders ...RESTStorageProvider) error

// 這里是裝載api的過程,其中serverstorage.APIResourceConfigSource配置的定義可以看cmd/kube-apiserver/app/server.go里的func CreateKubeAPIServerConfig, func buildGenericConfig 這里裝載了openapi生成的k8s-api的接口定義,k8s的open api是基于https://github.com/emicklei/go-restful實(shí)現(xiàn)的,整個(gè)apiserver項(xiàng)目里進(jìn)行handler的生成(https://github.com/kubernetes/apiserver)

文章未完結(jié)持續(xù)更新