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目前刚开始写一个月，一共写了18篇原创文章，文章目录如下：
istio防故障利器，你知道几个,istio新手不要读，太难！
不懂envoyfilter也敢说精通istio系列-http-rbac-不要只会用AuthorizationPolicy配置权限
不懂envoyfilter也敢说精通istio系列-02-http-corsFilter-不要只会vs
不懂envoyfilter也敢说精通istio系列-03-http-csrf filter-再也不用再代码里写csrf逻辑了
不懂envoyfilter也敢说精通istio系列http-jwt_authn-不要只会RequestAuthorization
不懂envoyfilter也敢说精通istio系列-05-fault-filter-故障注入不止是vs
不懂envoyfilter也敢说精通istio系列-06-http-match-配置路由不只是vs
不懂envoyfilter也敢说精通istio系列-07-负载均衡配置不止是dr
不懂envoyfilter也敢说精通istio系列-08-连接池和断路器
不懂envoyfilter也敢说精通istio系列-09-http-route filter
不懂envoyfilter也敢说精通istio系列-network filter-redis proxy
不懂envoyfilter也敢说精通istio系列-network filter-HttpConnectionManager
不懂envoyfilter也敢说精通istio系列-ratelimit-istio ratelimit完全手册
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type PortForwardOptions struct {//port-forward结构体
Namespace string
PodName string
RESTClient *restclient.RESTClient
Config *restclient.Config
PodClient corev1client.PodsGetter
Address []string
Ports []string
PortForwarder portForwarder
StopChannel chan struct{}
ReadyChannel chan struct{}
}//创建port-forward命令
func NewCmdPortForward(f cmdutil.Factory, streams genericclioptions.IOStreams) *cobra.Command {
opts := &PortForwardOptions{//初始化结构体
PortForwarder: &defaultPortForwarder{
IOStreams: streams,
},
}
cmd := &cobra.Command{//创建cobra命令
Use: "port-forward TYPE/NAME [options] [LOCAL_PORT:]REMOTE_PORT [...[LOCAL_PORT_N:]REMOTE_PORT_N]",
DisableFlagsInUseLine: true,
Short: i18n.T("Forward one or more local ports to a pod"),
Long: portforwardLong,
Example: portforwardExample,
Run: func(cmd *cobra.Command, args []string) {
if err := opts.Complete(f, cmd, args); err != nil {//先准备
cmdutil.CheckErr(err)
}
if err := opts.Validate(); err != nil {//校验
cmdutil.CheckErr(cmdutil.UsageErrorf(cmd, "%v", err.Error()))
}
if err := opts.RunPortForward(); err != nil {//运行
cmdutil.CheckErr(err)
}
},
}
cmdutil.AddPodRunningTimeoutFlag(cmd, defaultPodPortForwardWaitTimeout)//pod-running-timeout选项
cmd.Flags().StringSliceVar(&opts.Address, "address", []string{"localhost"}, "Addresses to listen on (comma separated). Only accepts IP addresses or localhost as a value. When localhost is supplied, kubectl will try to bind on both 127.0.0.1 and ::1 and will fail if neither of these addresses are available to bind.")//address选项
// TODO support UID
return cmd
}//准备函数
func (o *PortForwardOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args []string) error {
var err error
if len(args) < 2 {//参数小于2个报错
return cmdutil.UsageErrorf(cmd, "TYPE/NAME and list of ports are required for port-forward")
}
o.Namespace, _, err = f.ToRawKubeConfigLoader().Namespace()//设置namespace
if err != nil {
return err
}
builder := f.NewBuilder().
WithScheme(scheme.Scheme, scheme.Scheme.PrioritizedVersionsAllGroups()...).
ContinueOnError().
NamespaceParam(o.Namespace).DefaultNamespace()//构造result对象
getPodTimeout, err := cmdutil.GetPodRunningTimeoutFlag(cmd)//获取pod-running-timeout选项
if err != nil {
return cmdutil.UsageErrorf(cmd, err.Error())
}
resourceName := args[0]//获取资源
builder.ResourceNames("pods", resourceName)
obj, err := builder.Do().Object()//从result获取obj
if err != nil {
return err
}
forwardablePod, err := polymorphichelpers.AttachablePodForObjectFn(f, obj, getPodTimeout)//从obj获取forward的pod
if err != nil {
return err
}
o.PodName = forwardablePod.Name//设置pod名称
// handle service port mapping to target port if needed
switch t := obj.(type) {//断言obj类型
case *corev1.Service://如果是service
o.Ports, err = translateServicePortToTargetPort(args[1:], *t, *forwardablePod)//转换service的port
if err != nil {
return err
}
default://默认
o.Ports, err = convertPodNamedPortToNumber(args[1:], *forwardablePod)//转换pod的port
if err != nil {
return err
}
}
clientset, err := f.KubernetesClientSet()//获取clientset
if err != nil {
return err
}
o.PodClient = clientset.CoreV1()//从clientset获取podclient
o.Config, err = f.ToRESTConfig()//设置restconfig
if err != nil {
return err
}
o.RESTClient, err = f.RESTClient()//设置restClient
if err != nil {
return err
}
o.StopChannel = make(chan struct{}, 1)//定义通道
o.ReadyChannel = make(chan struct{})
return nil
}//校验
func (o PortForwardOptions) Validate() error {
if len(o.PodName) == 0 {//pod名称不能为空
return fmt.Errorf("pod name or resource type/name must be specified")
}
if len(o.Ports) < 1 {//端口不能小于个
return fmt.Errorf("at least 1 PORT is required for port-forward")
}
if o.PortForwarder == nil || o.PodClient == nil || o.RESTClient == nil || o.Config == nil {//这四个对象不能为空
return fmt.Errorf("client, client config, restClient, and portforwarder must be provided")
}
return nil
}//运行
func (o PortForwardOptions) RunPortForward() error {
pod, err := o.PodClient.Pods(o.Namespace).Get(o.PodName, metav1.GetOptions{})//获取pod
if err != nil {
return err
}
if pod.Status.Phase != corev1.PodRunning {//pod状态不为running返回错误
return fmt.Errorf("unable to forward port because pod is not running. Current status=%v", pod.Status.Phase)
}
signals := make(chan os.Signal, 1)
signal.Notify(signals, os.Interrupt)
defer signal.Stop(signals)
go func() {
<-signals
if o.StopChannel != nil {
close(o.StopChannel)
}
}()
req := o.RESTClient.Post().
Resource("pods").
Namespace(o.Namespace).
Name(pod.Name).
SubResource("portforward")//通过restclient的post方法后去request
return o.PortForwarder.ForwardPorts("POST", req.URL(), o)//执行forward
}
//执行forward
func (f *defaultPortForwarder) ForwardPorts(method string, url *url.URL, opts PortForwardOptions) error {
transport, upgrader, err := spdy.RoundTripperFor(opts.Config)//获取transport
if err != nil {
return err
}
dialer := spdy.NewDialer(upgrader, &http.Client{Transport: transport}, method, url)//获取dialer
fw, err := portforward.NewOnAddresses(dialer, opts.Address, opts.Ports, opts.StopChannel, opts.ReadyChannel, f.Out, f.ErrOut)//构造forwarder
if err != nil {
return err
}
return fw.ForwardPorts()//执行forward
}//拆分port
func splitPort(port string) (local, remote string) {
parts := strings.Split(port, ":")//用冒号分割
if len(parts) == 2 {//有两个
return parts[0], parts[1]
}
return parts[0], parts[0]
}//翻译svc port到target port
func translateServicePortToTargetPort(ports []string, svc corev1.Service, pod corev1.Pod) ([]string, error) {
var translated []string
for _, port := range ports {//遍历ports
localPort, remotePort := splitPort(port)//分割port
portnum, err := strconv.Atoi(remotePort)//把远程port转为整数
if err != nil {//如果转换失败
svcPort, err := util.LookupServicePortNumberByName(svc, remotePort)//通过名称查找service的port
if err != nil {
return nil, err
}
portnum = int(svcPort)//把svcPort转整数
if localPort == remotePort {//如果本地port和远程port相等
localPort = strconv.Itoa(portnum)
}
}
containerPort, err := util.LookupContainerPortNumberByServicePort(svc, pod, int32(portnum))//后去svc的target-port
if err != nil {
// can't resolve a named port, or Service did not declare this port, return an error
return nil, err
}
if int32(portnum) != containerPort {//如果容器的port的贝蒂svc的port不同则，
translated = append(translated, fmt.Sprintf("%s:%d", localPort, containerPort))
} else {
translated = append(translated, port)
}
}
return translated, nil
}func convertPodNamedPortToNumber(ports []string, pod corev1.Pod) ([]string, error) {
var converted []string
for _, port := range ports {//遍历ports
localPort, remotePort := splitPort(port)//分割port
containerPortStr := remotePort
_, err := strconv.Atoi(remotePort)//转换remoteport为整形
if err != nil {
containerPort, err := util.LookupContainerPortNumberByName(pod, remotePort)//从pod里查找port
if err != nil {
return nil, err
}
containerPortStr = strconv.Itoa(int(containerPort))
}
if localPort != remotePort {//如果本地port不等于远程port
converted = append(converted, fmt.Sprintf("%s:%s", localPort, containerPortStr))
} else {
converted = append(converted, containerPortStr)
}
}
return converted, nil
}
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