Add exec command

cmd/delete.go

@@ -31,7 +31,7 @@ func newDshDeleteCommand(
 func (sv *dshCmd) deletePods(
     ccontext string, namespace string, ds string, nodeName string,
 ) error {
-    clientset, err := getClientSet(ccontext)
+    clientset, _, err := getClientSet(ccontext)
     if err != nil {
         return err
     }

cmd/describe.go

@@ -39,7 +39,7 @@ func newDshDescribeCommand(
 func (sv *dshCmd) describePods(
     ccontext string, namespace string, ds string, nodeName string,
 ) error {
-    clientset, err := getClientSet(ccontext)
+    clientset, _, err := getClientSet(ccontext)
     if err != nil {
         return err
     }

cmd/dsh.go

@@ -41,5 +41,6 @@ func NewDshCommand(streams genericclioptions.IOStreams) *cobra.Command {
     dshCmd.AddCommand(newDshDescribeCommand(streams.Out, &context, &namespace, &nodeName))
     dshCmd.AddCommand(newDshLogCommand(streams.Out, &context, &namespace, &nodeName))
     dshCmd.AddCommand(newDshListCommand(streams.Out, &context, &namespace, &nodeName))
+    dshCmd.AddCommand(newDshExecCommand(streams.Out, &context, &namespace, &nodeName))
     return dshCmd
 }

cmd/exec.go

@@ -0,0 +1,183 @@
+package cmd
+
+import (
+    "context"
+    "errors"
+    "fmt"
+    "github.com/spf13/cobra"
+    "io"
+    "os"
+    "os/signal"
+    "syscall"
+
+    "k8s.io/client-go/kubernetes/scheme"
+    "k8s.io/client-go/tools/remotecommand"
+    "golang.org/x/term"
+
+    v1 "k8s.io/api/core/v1"
+)
+
+
+func newDshExecCommand(
+    out io.Writer, context *string, namespace *string, nodeName *string,
+) *cobra.Command {
+    var container string
+    var stdin bool
+    var tty bool
+
+    dshExec := &dshCmd{
+        out: out,
+    }
+
+    cmd := &cobra.Command{
+        Use:   "exec <daemonset> [<options>] -- <command> [args...]",
+        Short: "execute arbitrary commands in pod for <daemonset>",
+        Args: cobra.MatchAll(cobra.MinimumNArgs(1)),
+        RunE: func(cmd *cobra.Command, args []string) error {
+            if len(args) > 1 && cmd.ArgsLenAtDash() != -1 {
+                remoteCommand := args[cmd.ArgsLenAtDash():]
+                return dshExec.execPod(
+                    *context, *namespace, args[0], *nodeName, container, stdin,
+                    tty, remoteCommand,
+                )
+            } else {
+                return errors.New("At least some command is required")
+            }
+        },
+    }
+
+    cmd.Flags().StringVarP(
+        &container, "container", "c", "", "The container to exec into",
+    )
+    cmd.Flags().BoolVarP(
+        &stdin, "stdin", "i", false, "Pass stdin to the container",
+    )
+    cmd.Flags().BoolVarP(
+        &tty, "tty", "t", false, "Stdin is a TTY",
+    )
+    return cmd
+}
+
+type terminalSizeQueue struct {
+    sizeQueue chan remotecommand.TerminalSize
+}
+
+func (t *terminalSizeQueue) Next() *remotecommand.TerminalSize {
+    size, ok := <- t.sizeQueue
+    if !ok {
+        return nil
+    }
+    return &size
+}
+
+func monitorTerminalResize(sizeQueue chan remotecommand.TerminalSize) {
+    ch := make(chan os.Signal, 1)
+    signal.Notify(ch, syscall.SIGWINCH)
+    defer signal.Stop(ch)
+
+    for range ch {
+        if width, height, err := term.GetSize(int(os.Stdin.Fd())); err == nil {
+            sizeQueue <- remotecommand.TerminalSize{
+                Width: uint16(width), Height: uint16(height),
+            }
+        }
+    }
+}
+
+func (sv *dshCmd) execPod(
+    kcontext string, namespace string, ds string, nodeName string,
+    container string, stdin bool, tty bool, cmd []string,
+) error {
+    clientset, config, err := getClientSet(kcontext)
+    if err != nil {
+        return err
+    }
+
+    pods, err := getPodsForDaemonSet(clientset, ds, namespace, nodeName)
+    if err != nil {
+        return err
+    }
+
+    if len(pods) == 0 {
+        fmt.Printf("No pods found\n")
+        return nil
+    }
+
+    if len(pods) > 1 {
+        fmt.Printf("More than one pod found, wut?!")
+        return nil
+    }
+
+    req := clientset.CoreV1().RESTClient().
+        Post().
+        Resource("pods").
+        Name(pods[0].Name).
+        Namespace(namespace).
+        SubResource("exec").
+        VersionedParams(&v1.PodExecOptions{
+            Command:   cmd,
+            Container: container,
+            Stdin:     stdin,
+            Stdout:    true,
+            Stderr:    true,
+            TTY:       tty,
+        }, scheme.ParameterCodec)
+
+    exec, err := remotecommand.NewSPDYExecutor(config, "POST", req.URL())
+    if err != nil {
+        return err
+    }
+
+    var streamOptions remotecommand.StreamOptions
+    if tty {
+        initialState, err := term.MakeRaw(int(os.Stdin.Fd()))
+        if err != nil {
+            return err
+        }
+        defer func() {
+            if err := term.Restore(int(os.Stdin.Fd()), initialState); err != nil {
+                // Handle the error, e.g., log it or print it.
+                fmt.Fprintf(os.Stderr, "Error restoring terminal: %v\n", err)
+            }
+        }()
+
+        // This queue has to be made with size 1 so that sending the original
+        // size before there's a listener won't cause a freeze
+        sizeQueue := make(chan remotecommand.TerminalSize, 1)
+        tQueue := &terminalSizeQueue{sizeQueue: sizeQueue}
+
+        // Send the initial terminal size.
+        if width, height, err := term.GetSize(int(os.Stdin.Fd())); err == nil {
+            sizeQueue <- remotecommand.TerminalSize{
+                Width: uint16(width), Height: uint16(height),
+            }
+        }
+
+        go monitorTerminalResize(sizeQueue)
+
+        streamOptions = remotecommand.StreamOptions{
+            Stdin:             os.Stdin,
+            Stdout:            os.Stdout,
+            Stderr:            os.Stdout,
+            Tty:               tty,
+            TerminalSizeQueue: tQueue,
+        }
+    } else {
+        streamOptions = remotecommand.StreamOptions{
+            Stdin:  os.Stdin,
+            Stdout: os.Stdout,
+            Stderr: os.Stdout,
+            Tty:    tty,
+        }
+    }
+
+	if !stdin {
+		streamOptions.Stdin = nil
+	}
+
+    ctx, cancel := context.WithCancel(context.Background())
+    defer cancel()
+
+    err = exec.StreamWithContext(ctx, streamOptions)
+    return err
+}

cmd/get.go

@@ -48,7 +48,7 @@ func newDshGetCommand(
 func (sv *dshCmd) getPods(
     context string, namespace string, ds string, nodeName string, output string,
 ) error {
-    clientset, err := getClientSet(context)
+    clientset, _, err := getClientSet(context)
     if err != nil {
         return err
     }

cmd/list.go

@@ -39,7 +39,7 @@ func (sv *dshCmd) getDaemonSets(
         return errors.New("You must specify a node")
     }
 
-    clientset, err := getClientSet(context)
+    clientset, _, err := getClientSet(context)
     if err != nil {
         return err
     }

cmd/log.go

@@ -53,7 +53,7 @@ func (sv *dshCmd) getLogs(
     ccontext string, namespace string, ds string, nodeName string, container string,
     follow bool, lines *int,
 ) error {
-    clientset, err := getClientSet(ccontext)
+    clientset, _, err := getClientSet(ccontext)
     if err != nil {
         return err
     }

cmd/util.go

@@ -4,11 +4,12 @@ import (
     "context"
     "k8s.io/client-go/tools/clientcmd"
     "k8s.io/client-go/kubernetes"
+    "k8s.io/client-go/rest"
     corev1 "k8s.io/api/core/v1"
     metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
-func getClientSet(context string) (*kubernetes.Clientset, error) {
+func getClientSet(context string) (*kubernetes.Clientset, *rest.Config, error) {
     loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
     configOverrides := &clientcmd.ConfigOverrides{
         CurrentContext: context,
@@ -19,11 +20,11 @@ func getClientSet(context string) (*kubernetes.Clientset, error) {
 
     config, err := kubeConfig.ClientConfig()
     if err != nil {
-        return nil, err
+        return nil, nil, err
     }
 
     clientset, err := kubernetes.NewForConfig(config)
-    return clientset, err
+    return clientset, config, err
 }
 
 func getDaemonSetsForNode(

go.mod

@@ -4,6 +4,7 @@ go 1.21.4
 
 require (
 	github.com/spf13/cobra v1.8.0
+	golang.org/x/term v0.15.0
 	golang.org/x/text v0.14.0
 	gopkg.in/yaml.v3 v3.0.1
 	k8s.io/api v0.29.2
@@ -29,18 +30,21 @@ require (
 	github.com/google/gofuzz v1.2.0 // indirect
 	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
 	github.com/google/uuid v1.3.0 // indirect
+	github.com/gorilla/websocket v1.5.0 // indirect
 	github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7 // indirect
 	github.com/imdario/mergo v0.3.6 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/moby/spdystream v0.2.0 // indirect
 	github.com/moby/term v0.0.0-20221205130635-1aeaba878587 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/monochromegane/go-gitignore v0.0.0-20200626010858-205db1a8cc00 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f // indirect
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
@@ -50,7 +54,6 @@ require (
 	golang.org/x/oauth2 v0.10.0 // indirect
 	golang.org/x/sync v0.5.0 // indirect
 	golang.org/x/sys v0.15.0 // indirect
-	golang.org/x/term v0.15.0 // indirect
 	golang.org/x/time v0.3.0 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect

go.sum

@@ -2,6 +2,8 @@ cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMT
 github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 h1:UQHMgLO+TxOElx5B5HZ4hJQsoJ/PvUvKRhJHDQXO8P8=
 github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1/go.mod h1:xomTg63KZ2rFqZQzSB4Vz2SUXa1BpHTVz9L5PTmPC4E=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5 h1:0CwZNZbxp69SHPdPJAN/hZIm0C4OItdklCFmMRWYpio=
+github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5/go.mod h1:wHh0iHkYZB8zMSxRWpUBQtwG5a7fFgvEO+odwuTv2gs=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
@@ -71,6 +73,9 @@ github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 h1:El6M4kTTCOh6aBiKaU
 github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510/go.mod h1:pupxD2MaaD3pAXIBCelhxNneeOaAeabZDe5s4K6zSpQ=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
+github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7 h1:pdN6V1QBWetyv/0+wjACpqVH+eVULgEjkurDLq3goeM=
 github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7/go.mod h1:FecbI9+v66THATjSRHfNgh1IVFe/9kFxbXtjV0ctIMA=
 github.com/imdario/mergo v0.3.6 h1:xTNEAn+kxVO7dTZGu0CegyqKZmoWFI0rF8UxjlB2d28=
@@ -94,6 +99,8 @@ github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de h1:9TO3cAIGXtEhn
 github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de/go.mod h1:zAbeS9B/r2mtpb6U+EI2rYA5OAXxsYw6wTamcNW+zcE=
 github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=
 github.com/mailru/easyjson v0.7.7/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
+github.com/moby/spdystream v0.2.0 h1:cjW1zVyyoiM0T7b6UoySUFqzXMoqRckQtXwGPiBhOM8=
+github.com/moby/spdystream v0.2.0/go.mod h1:f7i0iNDQJ059oMTcWxx8MA/zKFIuD/lY+0GqbN2Wy8c=
 github.com/moby/term v0.0.0-20221205130635-1aeaba878587 h1:HfkjXDfhgVaN5rmueG8cL8KKeFNecRCXFhaJ2qZ5SKA=
 github.com/moby/term v0.0.0-20221205130635-1aeaba878587/go.mod h1:8FzsFHVUBGZdbDsJw/ot+X+d5HLUbvklYLJ9uGfcI3Y=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
@@ -105,6 +112,8 @@ github.com/monochromegane/go-gitignore v0.0.0-20200626010858-205db1a8cc00 h1:n6/
 github.com/monochromegane/go-gitignore v0.0.0-20200626010858-205db1a8cc00/go.mod h1:Pm3mSP3c5uWn86xMLZ5Sa7JB9GsEZySvHYXCTK4E9q4=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
+github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f h1:y5//uYreIhSUg3J1GEMiLbxo1LJaP8RfCpH6pymGZus=
+github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f/go.mod h1:ZdcZmHo+o7JKHSa8/e818NopupXU1YMK5fe1lsApnBw=
 github.com/onsi/ginkgo/v2 v2.13.0 h1:0jY9lJquiL8fcf3M4LAXN5aMlS/b2BV86HFFPCPMgE4=
 github.com/onsi/ginkgo/v2 v2.13.0/go.mod h1:TE309ZR8s5FsKKpuB1YAQYBzCaAfUgatB/xlT/ETL/o=
 github.com/onsi/gomega v1.29.0 h1:KIA/t2t5UBzoirT4H9tsML45GEbo3ouUnBHsCfD2tVg=