Add generic cli options (#283)

README.md

@@ -77,15 +77,15 @@ Supported Kubernetes resources are `pod`, `replicationcontroller`, `service`, `d
  `--config`                  | `~/.config/stern/config.yaml` | Path to the stern config file
  `--container`, `-c`         | `.*`                          | Container name when multiple containers in pod. (regular expression)
  `--container-state`         | `all`                         | Tail containers with state in running, waiting, terminated, or all. 'all' matches all container states. To specify multiple states, repeat this or set comma-separated value.
- `--context`                 |                               | Kubernetes context to use. Default to current context configured in kubeconfig.
+ `--context`                 |                               | The name of the kubeconfig context to use
  `--ephemeral-containers`    | `true`                        | Include or exclude ephemeral containers.
  `--exclude`, `-e`           | `[]`                          | Log lines to exclude. (regular expression)
  `--exclude-container`, `-E` | `[]`                          | Container name to exclude when multiple containers in pod. (regular expression)
  `--exclude-pod`             | `[]`                          | Pod name to exclude. (regular expression)
  `--field-selector`          |                               | Selector (field query) to filter on. If present, default to ".*" for the pod-query.
  `--include`, `-i`           | `[]`                          | Log lines to include. (regular expression)
  `--init-containers`         | `true`                        | Include or exclude init containers.
- `--kubeconfig`              |                               | Path to kubeconfig file to use. Default to KUBECONFIG variable then ~/.kube/config path.
+ `--kubeconfig`              |                               | Path to the kubeconfig file to use for CLI requests.
  `--max-log-requests`        | `-1`                          | Maximum number of concurrent logs to request. Defaults to 50, but 5 when specifying --no-follow
  `--namespace`, `-n`         |                               | Kubernetes namespace to use. Default to namespace configured in kubernetes context. To specify multiple namespaces, repeat this or set comma-separated value.
  `--no-follow`               | `false`                       | Exit when all logs have been shown.
@@ -94,6 +94,7 @@ Supported Kubernetes resources are `pod`, `replicationcontroller`, `service`, `d
  `--output`, `-o`            | `default`                     | Specify predefined template. Currently support: [default, raw, json, extjson, ppextjson]
  `--prompt`, `-p`            | `false`                       | Toggle interactive prompt for selecting 'app.kubernetes.io/instance' label values.
  `--selector`, `-l`          |                               | Selector (label query) to filter on. If present, default to ".*" for the pod-query.
+ `--show-hidden-options`     | `false`                       | Print a list of hidden options.
  `--since`, `-s`             | `48h0m0s`                     | Return logs newer than a relative duration like 5s, 2m, or 3h.
  `--tail`                    | `-1`                          | The number of lines from the end of the logs to show. Defaults to -1, showing all logs.
  `--template`                |                               | Template to use for log lines, leave empty to use --output flag.

cmd/cmd.go

@@ -38,13 +38,19 @@ import (
 	"k8s.io/apimachinery/pkg/fields"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/clientcmd"
 	"k8s.io/klog/v2"
+
+	// load all auth plugins
+	_ "k8s.io/client-go/plugin/pkg/client/auth"
 )
 
 // Use "~" to avoid exposing the user name in the help message
 var defaultConfigFilePath = "~/.config/stern/config.yaml"
 
 type options struct {
+	configFlags *genericclioptions.ConfigFlags
 	genericclioptions.IOStreams
 
 	excludePod          []string
@@ -54,9 +60,7 @@ type options struct {
 	timestamps          string
 	timezone            string
 	since               time.Duration
-	context             string
 	namespaces          []string
-	kubeConfig          string
 	exclude             []string
 	include             []string
 	initContainers      bool
@@ -80,11 +84,20 @@ type options struct {
 	maxLogRequests      int
 	node                string
 	configFilePath      string
+	showHiddenOptions   bool
+
+	client       kubernetes.Interface
+	clientConfig clientcmd.ClientConfig
 }
 
 func NewOptions(streams genericclioptions.IOStreams) *options {
+	configFlags := genericclioptions.NewConfigFlags(true)
+	// stern has its own namespace flag, so disable the one in configFlags
+	configFlags.Namespace = nil
+
 	return &options{
-		IOStreams: streams,
+		configFlags: configFlags,
+		IOStreams:   streams,
 
 		color:               "auto",
 		container:           ".*",
@@ -119,6 +132,23 @@ func (o *options) Complete(args []string) error {
 		o.configFilePath = envVar
 	}
 
+	o.clientConfig = o.configFlags.ToRawKubeConfigLoader()
+
+	restConfig, err := o.configFlags.ToRESTConfig()
+	if err != nil {
+		return err
+	}
+
+	o.client = kubernetes.NewForConfigOrDie(restConfig)
+
+	if len(o.namespaces) == 0 {
+		namespace, _, err := o.clientConfig.Namespace()
+		if err != nil {
+			return err
+		}
+		o.namespaces = []string{namespace}
+	}
+
 	return nil
 }
 
@@ -147,12 +177,12 @@ func (o *options) Run(cmd *cobra.Command) error {
 	defer cancel()
 
 	if o.prompt {
-		if err := promptHandler(ctx, config, o.Out); err != nil {
+		if err := promptHandler(ctx, o.client, config, o.Out); err != nil {
 			return err
 		}
 	}
 
-	return stern.Run(ctx, config)
+	return stern.Run(ctx, o.client, config)
 }
 
 func (o *options) sternConfig() (*stern.Config, error) {
@@ -257,8 +287,6 @@ func (o *options) sternConfig() (*stern.Config, error) {
 	}
 
 	return &stern.Config{
-		KubeConfig:            o.kubeConfig,
-		ContextName:           o.context,
 		Namespaces:            namespaces,
 		PodQuery:              pod,
 		ExcludePodQuery:       excludePod,
@@ -351,22 +379,20 @@ func (o *options) overrideFlagSetDefaultFromConfig(fs *pflag.FlagSet) error {
 
 // AddFlags adds all the flags used by stern.
 func (o *options) AddFlags(fs *pflag.FlagSet) {
+	o.addKubernetesFlags(fs)
+
 	fs.BoolVarP(&o.allNamespaces, "all-namespaces", "A", o.allNamespaces, "If present, tail across all namespaces. A specific namespace is ignored even if specified with --namespace.")
 	fs.StringVar(&o.color, "color", o.color, "Force set color output. 'auto':  colorize if tty attached, 'always': always colorize, 'never': never colorize.")
 	fs.StringVar(&o.completion, "completion", o.completion, "Output stern command-line completion code for the specified shell. Can be 'bash', 'zsh' or 'fish'.")
 	fs.StringVarP(&o.container, "container", "c", o.container, "Container name when multiple containers in pod. (regular expression)")
 	fs.StringSliceVar(&o.containerStates, "container-state", o.containerStates, "Tail containers with state in running, waiting, terminated, or all. 'all' matches all container states. To specify multiple states, repeat this or set comma-separated value.")
-	fs.StringVar(&o.context, "context", o.context, "Kubernetes context to use. Default to current context configured in kubeconfig.")
 	fs.StringArrayVarP(&o.exclude, "exclude", "e", o.exclude, "Log lines to exclude. (regular expression)")
 	fs.StringArrayVarP(&o.excludeContainer, "exclude-container", "E", o.excludeContainer, "Container name to exclude when multiple containers in pod. (regular expression)")
 	fs.StringArrayVar(&o.excludePod, "exclude-pod", o.excludePod, "Pod name to exclude. (regular expression)")
 	fs.BoolVar(&o.noFollow, "no-follow", o.noFollow, "Exit when all logs have been shown.")
 	fs.StringArrayVarP(&o.include, "include", "i", o.include, "Log lines to include. (regular expression)")
 	fs.BoolVar(&o.initContainers, "init-containers", o.initContainers, "Include or exclude init containers.")
 	fs.BoolVar(&o.ephemeralContainers, "ephemeral-containers", o.ephemeralContainers, "Include or exclude ephemeral containers.")
-	fs.StringVar(&o.kubeConfig, "kubeconfig", o.kubeConfig, "Path to kubeconfig file to use. Default to KUBECONFIG variable then ~/.kube/config path.")
-	fs.StringVar(&o.kubeConfig, "kube-config", o.kubeConfig, "Path to kubeconfig file to use.")
-	_ = fs.MarkDeprecated("kube-config", "Use --kubeconfig instead.")
 	fs.StringSliceVarP(&o.namespaces, "namespace", "n", o.namespaces, "Kubernetes namespace to use. Default to namespace configured in kubernetes context. To specify multiple namespaces, repeat this or set comma-separated value.")
 	fs.StringVar(&o.node, "node", o.node, "Node name to filter on.")
 	fs.IntVar(&o.maxLogRequests, "max-log-requests", o.maxLogRequests, "Maximum number of concurrent logs to request. Defaults to 50, but 5 when specifying --no-follow")
@@ -384,10 +410,39 @@ func (o *options) AddFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&o.configFilePath, "config", o.configFilePath, "Path to the stern config file")
 	fs.IntVar(&o.verbosity, "verbosity", o.verbosity, "Number of the log level verbosity")
 	fs.BoolVarP(&o.version, "version", "v", o.version, "Print the version and exit.")
+	fs.BoolVar(&o.showHiddenOptions, "show-hidden-options", o.showHiddenOptions, "Print a list of hidden options.")
 
 	fs.Lookup("timestamps").NoOptDefVal = "default"
 }
 
+func (o *options) addKubernetesFlags(fs *pflag.FlagSet) {
+	flagset := pflag.NewFlagSet("", pflag.ExitOnError)
+	o.configFlags.AddFlags(flagset)
+	flagset.VisitAll(func(f *pflag.Flag) {
+		// Hide Kubernetes flags except some
+		if !(f.Name == "kubeconfig" || f.Name == "context") {
+			f.Hidden = true
+		}
+
+		// `server` flag in configFlags has `s` shorthand, which is used by stern
+		// as shorthand for `since` flag, so do not use it.
+		if f.Name == "server" {
+			f.Shorthand = ""
+		}
+	})
+	fs.AddFlagSet(flagset)
+}
+
+func (o *options) outputHiddenOptions() {
+	fs := pflag.NewFlagSet("", pflag.ExitOnError)
+	o.AddFlags(fs)
+	fs.VisitAll(func(f *pflag.Flag) {
+		f.Hidden = !f.Hidden
+	})
+	fmt.Println("The following options can also be used in stern:")
+	fs.PrintDefaults()
+}
+
 func (o *options) generateTemplate() (*template.Template, error) {
 	t := o.template
 	if o.templateFile != "" {
@@ -588,6 +643,11 @@ func NewSternCmd(stream genericclioptions.IOStreams) (*cobra.Command, error) {
 				return runCompletion(o.completion, cmd, o.Out)
 			}
 
+			if o.showHiddenOptions {
+				o.outputHiddenOptions()
+				return nil
+			}
+
 			if err := o.Complete(args); err != nil {
 				return err
 			}
@@ -607,6 +667,8 @@ func NewSternCmd(stream genericclioptions.IOStreams) (*cobra.Command, error) {
 		ValidArgsFunction: queryCompletionFunc(o),
 	}
 
+	cmd.SetUsageTemplate(cmd.UsageTemplate() + "\nUse \"stern --show-hidden-options\" for a list of hidden command-line options.\n")
+
 	o.AddFlags(cmd.Flags())
 
 	if err := registerCompletionFuncForFlags(cmd, o); err != nil {

cmd/cmd_test.go

@@ -448,8 +448,6 @@ func TestOptionsSternConfig(t *testing.T) {
 
 	defaultConfig := func() *stern.Config {
 		return &stern.Config{
-			KubeConfig:            "",
-			ContextName:           "",
 			Namespaces:            []string{},
 			PodQuery:              re(""),
 			ExcludePodQuery:       nil,
@@ -495,8 +493,6 @@ func TestOptionsSternConfig(t *testing.T) {
 			"change all options",
 			func() *options {
 				o := NewOptions(streams)
-				o.kubeConfig = "kubeconfig1"
-				o.context = "context1"
 				o.namespaces = []string{"ns1", "ns2"}
 				o.podQuery = "query1"
 				o.excludePod = []string{"exp1", "exp2"}
@@ -524,8 +520,6 @@ func TestOptionsSternConfig(t *testing.T) {
 			}(),
 			func() *stern.Config {
 				c := defaultConfig()
-				c.KubeConfig = "kubeconfig1"
-				c.ContextName = "context1"
 				c.Namespaces = []string{"ns1", "ns2"}
 				c.PodQuery = re("query1")
 				c.ExcludePodQuery = []*regexp.Regexp{re("exp1"), re("exp2")}

cmd/flag_completion.go

@@ -23,10 +23,9 @@ import (
 
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
-	"github.com/stern/stern/kubernetes"
 	"github.com/stern/stern/stern"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/kubernetes"
 )
 
 var flagChoices = map[string][]string{
@@ -99,13 +98,11 @@ func registerCompletionFuncForFlags(cmd *cobra.Command, o *options) error {
 // that match the toComplete prefix.
 func namespaceCompletionFunc(o *options) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		clientConfig := kubernetes.NewClientConfig(o.kubeConfig, o.context)
-		clientset, err := kubernetes.NewClientSet(clientConfig)
-		if err != nil {
+		if err := o.Complete(nil); err != nil {
 			return compError(err)
 		}
 
-		namespaceList, err := clientset.CoreV1().Namespaces().List(context.TODO(), metav1.ListOptions{})
+		namespaceList, err := o.client.CoreV1().Namespaces().List(context.TODO(), metav1.ListOptions{})
 		if err != nil {
 			return compError(err)
 		}
@@ -125,13 +122,11 @@ func namespaceCompletionFunc(o *options) func(cmd *cobra.Command, args []string,
 // that match the toComplete prefix.
 func nodeCompletionFunc(o *options) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		clientConfig := kubernetes.NewClientConfig(o.kubeConfig, o.context)
-		clientset, err := kubernetes.NewClientSet(clientConfig)
-		if err != nil {
+		if err := o.Complete(nil); err != nil {
 			return compError(err)
 		}
 
-		nodeList, err := clientset.CoreV1().Nodes().List(context.TODO(), metav1.ListOptions{})
+		nodeList, err := o.client.CoreV1().Nodes().List(context.TODO(), metav1.ListOptions{})
 		if err != nil {
 			return compError(err)
 		}
@@ -151,14 +146,16 @@ func nodeCompletionFunc(o *options) func(cmd *cobra.Command, args []string, toCo
 // that match the toComplete prefix.
 func contextCompletionFunc(o *options) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		clientConfig := kubernetes.NewClientConfig(o.kubeConfig, o.context)
-		config, err := clientConfig.RawConfig()
-		if err != nil {
+		if err := o.Complete(nil); err != nil {
 			return compError(err)
 		}
 
 		var comps []string
-		for name := range config.Contexts {
+		kubeConfig, err := o.clientConfig.RawConfig()
+		if err != nil {
+			return compError(err)
+		}
+		for name := range kubeConfig.Contexts {
 			if strings.HasPrefix(name, toComplete) {
 				comps = append(comps, name)
 			}
@@ -172,6 +169,10 @@ func contextCompletionFunc(o *options) func(cmd *cobra.Command, args []string, t
 // that match the toComplete prefix.
 func queryCompletionFunc(o *options) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+		if err := o.Complete(nil); err != nil {
+			return compError(err)
+		}
+
 		var comps []string
 		parts := strings.Split(toComplete, "/")
 		if len(parts) != 2 {
@@ -191,24 +192,19 @@ func queryCompletionFunc(o *options) func(cmd *cobra.Command, args []string, toC
 			return compError(errors.New("multiple namespaces are not supported"))
 		}
 
-		clientConfig := kubernetes.NewClientConfig(o.kubeConfig, o.context)
-		clientset, err := kubernetes.NewClientSet(clientConfig)
-		if err != nil {
-			return compError(err)
-		}
 		var namespace string
 		if len(uniqueNamespaces) == 1 {
 			namespace = uniqueNamespaces[0]
 		} else {
-			n, _, err := clientConfig.Namespace()
+			n, _, err := o.clientConfig.Namespace()
 			if err != nil {
 				return compError(err)
 			}
 			namespace = n
 		}
 
 		kind, name := parts[0], parts[1]
-		names, err := retrieveNamesFromResource(context.TODO(), clientset, namespace, kind)
+		names, err := retrieveNamesFromResource(context.TODO(), o.client, namespace, kind)
 		if err != nil {
 			return compError(err)
 		}
@@ -226,7 +222,7 @@ func compError(err error) ([]string, cobra.ShellCompDirective) {
 	return nil, cobra.ShellCompDirectiveError
 }
 
-func retrieveNamesFromResource(ctx context.Context, client clientset.Interface, namespace, kind string) ([]string, error) {
+func retrieveNamesFromResource(ctx context.Context, client kubernetes.Interface, namespace, kind string) ([]string, error) {
 	opt := metav1.ListOptions{}
 	var names []string
 	switch {

cmd/flag_prompt.go

@@ -11,11 +11,12 @@ import (
 	"github.com/pkg/errors"
 	"github.com/stern/stern/stern"
 	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/client-go/kubernetes"
 )
 
 // promptHandler invokes the interactive prompt and updates config.LabelSelector with the selected value.
-func promptHandler(ctx context.Context, config *stern.Config, out io.Writer) error {
-	labelsMap, err := stern.List(ctx, config)
+func promptHandler(ctx context.Context, client kubernetes.Interface, config *stern.Config, out io.Writer) error {
+	labelsMap, err := stern.List(ctx, client, config)
 	if err != nil {
 		return err
 	}

hack/update-readme/update-readme.go

@@ -59,6 +59,10 @@ func GenerateFlagsMarkdownTable() string {
 			return
 		}
 
+		if flag.Hidden {
+			return
+		}
+
 		flagText := ""
 		if flag.Shorthand != "" {
 			flagText = fmt.Sprintf(" `--%s`, `-%s` ", flag.Name, flag.Shorthand)