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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 ExposeServiceOptions struct {//expose结构体
FilenameOptions resource.FilenameOptions
RecordFlags *genericclioptions.RecordFlags
PrintFlags *genericclioptions.PrintFlags
PrintObj printers.ResourcePrinterFunc
DryRun bool
EnforceNamespace bool
Generators func(string) map[string]generate.Generator
CanBeExposed polymorphichelpers.CanBeExposedFunc
MapBasedSelectorForObject func(runtime.Object) (string, error)
PortsForObject polymorphichelpers.PortsForObjectFunc
ProtocolsForObject func(runtime.Object) (map[string]string, error)
Namespace string
Mapper meta.RESTMapper
DynamicClient dynamic.Interface
Builder *resource.Builder
Recorder genericclioptions.Recorder
genericclioptions.IOStreams
}
unc NewExposeServiceOptions(ioStreams genericclioptions.IOStreams) *ExposeServiceOptions {
return &ExposeServiceOptions{//创建expose结构体
RecordFlags: genericclioptions.NewRecordFlags(),
PrintFlags: genericclioptions.NewPrintFlags("exposed").WithTypeSetter(scheme.Scheme),
Recorder: genericclioptions.NoopRecorder{},
IOStreams: ioStreams,
}
}
//创建expose命令
func NewCmdExposeService(f cmdutil.Factory, streams genericclioptions.IOStreams) *cobra.Command {
o := NewExposeServiceOptions(streams)//初始化结构体
validArgs := []string{}
resources := regexp.MustCompile(`\s*,`).Split(exposeResources, -1)
for _, r := range resources {
validArgs = append(validArgs, strings.Fields(r)[0])//设置有效参数
}
cmd := &cobra.Command{//创建cobra命令
Use: "expose (-f FILENAME | TYPE NAME) [--port=port] [--protocol=TCP|UDP|SCTP] [--target-port=number-or-name] [--name=name] [--external-ip=external-ip-of-service] [--type=type]",
DisableFlagsInUseLine: true,
Short: i18n.T("Take a replication controller, service, deployment or pod and expose it as a new Kubernetes Service"),
Long: exposeLong,
Example: exposeExample,
Run: func(cmd *cobra.Command, args []string) {
cmdutil.CheckErr(o.Complete(f, cmd))//准备运行
cmdutil.CheckErr(o.RunExpose(cmd, args))运行
},
ValidArgs: validArgs,
}
o.RecordFlags.AddFlags(cmd)//设置record选项
o.PrintFlags.AddFlags(cmd)//设置print选项
cmd.Flags().String("generator", "service/v2", i18n.T("The name of the API generator to use. There are 2 generators: 'service/v1' and 'service/v2'. The only difference between them is that service port in v1 is named 'default', while it is left unnamed in v2. Default is 'service/v2'."))//设置generator选项
cmd.Flags().String("protocol", "", i18n.T("The network protocol for the service to be created. Default is 'TCP'."))//设置protocol选项
cmd.Flags().String("port", "", i18n.T("The port that the service should serve on. Copied from the resource being exposed, if unspecified"))//设置port选项
cmd.Flags().String("type", "", i18n.T("Type for this service: ClusterIP, NodePort, LoadBalancer, or ExternalName. Default is 'ClusterIP'."))//设置type选项
cmd.Flags().String("load-balancer-ip", "", i18n.T("IP to assign to the LoadBalancer. If empty, an ephemeral IP will be created and used (cloud-provider specific)."))//设置load-balancer-ip选项
cmd.Flags().String("selector", "", i18n.T("A label selector to use for this service. Only equality-based selector requirements are supported. If empty (the default) infer the selector from the replication controller or replica set.)"))//设置selector选项
cmd.Flags().StringP("labels", "l", "", "Labels to apply to the service created by this call.")//设置labels选项
cmd.Flags().String("container-port", "", i18n.T("Synonym for --target-port"))
cmd.Flags().MarkDeprecated("container-port", "--container-port will be removed in the future, please use --target-port instead")
cmd.Flags().String("target-port", "", i18n.T("Name or number for the port on the container that the service should direct traffic to. Optional."))//设置target-port选项
cmd.Flags().String("external-ip", "", i18n.T("Additional external IP address (not managed by Kubernetes) to accept for the service. If this IP is routed to a node, the service can be accessed by this IP in addition to its generated service IP."))//设置external-ip选项
cmd.Flags().String("overrides", "", i18n.T("An inline JSON override for the generated object. If this is non-empty, it is used to override the generated object. Requires that the object supply a valid apiVersion field."))//设置overrides选项
cmd.Flags().String("name", "", i18n.T("The name for the newly created object."))//设置name选项
cmd.Flags().String("session-affinity", "", i18n.T("If non-empty, set the session affinity for the service to this; legal values: 'None', 'ClientIP'"))//设置session-affinity选项
cmd.Flags().String("cluster-ip", "", i18n.T("ClusterIP to be assigned to the service. Leave empty to auto-allocate, or set to 'None' to create a headless service."))//设置cluster-ip选项
usage := "identifying the resource to expose a service"
cmdutil.AddFilenameOptionFlags(cmd, &o.FilenameOptions, usage)//设置-f选项
cmdutil.AddDryRunFlag(cmd)//设置dry-run选项
cmdutil.AddApplyAnnotationFlags(cmd)//设置save-config选项
return cmd
}
//准备函数
func (o *ExposeServiceOptions) Complete(f cmdutil.Factory, cmd *cobra.Command) error {
o.DryRun = cmdutil.GetDryRunFlag(cmd)//设置dry-run
if o.DryRun {
o.PrintFlags.Complete("%s (dry run)")
}
printer, err := o.PrintFlags.ToPrinter()//print flag转printer
if err != nil {
return err
}
o.PrintObj = printer.PrintObj//设置printObj函数
o.RecordFlags.Complete(cmd)//record 准备
o.Recorder, err = o.RecordFlags.ToRecorder()//record flag转recorder
if err != nil {
return err
}
o.DynamicClient, err = f.DynamicClient()//设置client
if err != nil {
return err
}
o.Generators = generateversioned.GeneratorFn//获取generator函数
o.Builder = f.NewBuilder()//设置builder
o.CanBeExposed = polymorphichelpers.CanBeExposedFn//是否可expose函数
o.MapBasedSelectorForObject = polymorphichelpers.MapBasedSelectorForObjectFn//从对象获取selector函数
o.ProtocolsForObject = polymorphichelpers.ProtocolsForObjectFn//从对象获取protocol函数
o.PortsForObject = polymorphichelpers.PortsForObjectFn//从对象获取port函数
o.Mapper, err = f.ToRESTMapper()//设置mapper
if err != nil {
return err
}
o.Namespace, o.EnforceNamespace, err = f.ToRawKubeConfigLoader().Namespace()//设置namespace,enforceNamespace
if err != nil {
return err
}
return err
}
//运行
func (o *ExposeServiceOptions) RunExpose(cmd *cobra.Command, args []string) error {
r := o.Builder.
WithScheme(scheme.Scheme, scheme.Scheme.PrioritizedVersionsAllGroups()...).
ContinueOnError().
NamespaceParam(o.Namespace).DefaultNamespace().
FilenameParam(o.EnforceNamespace, &o.FilenameOptions).
ResourceTypeOrNameArgs(false, args...).
Flatten().
Do()//构造Result对象
err := r.Err()
if err != nil {
return cmdutil.UsageErrorf(cmd, err.Error())
}
// Get the generator, setup and validate all required parameters
generatorName := cmdutil.GetFlagString(cmd, "generator")//获取generator name
generators := o.Generators("expose")//获取generator map
generator, found := generators[generatorName]//获取generator
if !found {
return cmdutil.UsageErrorf(cmd, "generator %q not found.", generatorName)
}
names := generator.ParamNames()//获取generator参数名称
err = r.Visit(func(info *resource.Info, err error) error {//访问result对象
if err != nil {
return err
}
mapping := info.ResourceMapping()//获取mapping
if err := o.CanBeExposed(mapping.GroupVersionKind.GroupKind()); err != nil {//判断是否可以export
return err
}
params := generate.MakeParams(cmd, names)//构造generator Params
name := info.Name
if len(name) > validation.DNS1035LabelMaxLength {//判断名称是否超出长度
name = name[:validation.DNS1035LabelMaxLength]
}
params["default-name"] = name//设置generator params
// For objects that need a pod selector, derive it from the exposed object in case a user
// didn't explicitly specify one via --selector
if s, found := params["selector"]; found && generate.IsZero(s) {从参数获取selector,如果存在并为空
s, err := o.MapBasedSelectorForObject(info.Object)//从Info对象里获取selector
if err != nil {
return cmdutil.UsageErrorf(cmd, "couldn't retrieve selectors via --selector flag or introspection: %v", err)
}
params["selector"] = s//设置selector参数
}
isHeadlessService := params["cluster-ip"] == "None"//设置是否无头service
// For objects that need a port, derive it from the exposed object in case a user
// didn't explicitly specify one via --port
if port, found := params["port"]; found && generate.IsZero(port) {//从params获取port,如果存在并且为空
ports, err := o.PortsForObject(info.Object)//从info对象获取prots
if err != nil {
return cmdutil.UsageErrorf(cmd, "couldn't find port via --port flag or introspection: %v", err)
}
switch len(ports) {
case 0:
if !isHeadlessService {
return cmdutil.UsageErrorf(cmd, "couldn't find port via --port flag or introspection")
}
case 1:
params["port"] = ports[0]
default:
params["ports"] = strings.Join(ports, ",")
}
}
// Always try to derive protocols from the exposed object, may use
// different protocols for different ports.
if _, found := params["protocol"]; found {//从参数里获取protocol,如果存在
protocolsMap, err := o.ProtocolsForObject(info.Object)//从info里获取protocol
if err != nil {
return cmdutil.UsageErrorf(cmd, "couldn't find protocol via introspection: %v", err)
}
if protocols := generate.MakeProtocols(protocolsMap); !generate.IsZero(protocols) {
params["protocols"] = protocols//设置protocols参数
}
}
if generate.IsZero(params["labels"]) {//从params获取labels,并且为空
labels, err := meta.NewAccessor().Labels(info.Object)//从info对象获取labels
if err != nil {
return err
}
params["labels"] = polymorphichelpers.MakeLabels(labels)//设置labels
}
if err = generate.ValidateParams(names, params); err != nil {//验证参数是否有效
return err
}
// Check for invalid flags used against the present generator.
if err := generate.EnsureFlagsValid(cmd, generators, generatorName); err != nil {//验证flag是否有效
return err
}
// Generate new object
object, err := generator.Generate(params)//从generator生成对象
if err != nil {
return err
}
if inline := cmdutil.GetFlagString(cmd, "overrides"); len(inline) > 0 {//如果overrides不为空
codec := runtime.NewCodec(scheme.DefaultJSONEncoder(), scheme.Codecs.UniversalDecoder(scheme.Scheme.PrioritizedVersionsAllGroups()...))
object, err = cmdutil.Merge(codec, object, inline)//合并对象和overrides
if err != nil {
return err
}
}
if err := o.Recorder.Record(object); err != nil {//设置change-cause注解
klog.V(4).Infof("error recording current command: %v", err)
}
if o.DryRun {//干跑打印结果
return o.PrintObj(object, o.Out)
}
if err := util.CreateOrUpdateAnnotation(cmdutil.GetFlagBool(cmd, cmdutil.ApplyAnnotationsFlag), object, scheme.DefaultJSONEncoder()); err != nil {//设置last-applied-configuration注解
return err
}
asUnstructured := &unstructured.Unstructured{}
if err := scheme.Scheme.Convert(object, asUnstructured, nil); err != nil {//把对象转为非结构化的
return err
}
gvks, _, err := unstructuredscheme.NewUnstructuredObjectTyper().ObjectKinds(asUnstructured)//获取groupversionkinds
if err != nil {
return err
}
objMapping, err := o.Mapper.RESTMapping(gvks[0].GroupKind(), gvks[0].Version)//获取mapping
if err != nil {
return err
}
// Serialize the object with the annotation applied.
actualObject, err := o.DynamicClient.Resource(objMapping.Resource).Namespace(o.Namespace).Create(asUnstructured, metav1.CreateOptions{})//创建service对象
if err != nil {
return err
}
return o.PrintObj(actualObject, o.Out)//打印结果
})
if err != nil {
return err
}
return nil
}