feat(cmd): support custom images for tracerunner and init container

Signed-off-by: Leonardo Di Donato <[email protected]>
Co-Authored-By: Lorenzo Fontana <[email protected]>

Author: leodido

pkg/cmd/get.go

@@ -111,6 +111,7 @@ func (o *GetOptions) Validate(cmd *cobra.Command, args []string) error {
 	return nil
 }
 
+// Complete completes the setup of the command.
 func (o *GetOptions) Complete(factory factory.Factory, cmd *cobra.Command, args []string) error {
 	// Prepare namespace
 	var err error
@@ -125,7 +126,7 @@ func (o *GetOptions) Complete(factory factory.Factory, cmd *cobra.Command, args
 		o.namespace = ""
 	}
 
-	//// Prepare client
+	// Prepare client
 	o.clientConfig, err = factory.ToRESTConfig()
 	if err != nil {
 		return err

pkg/cmd/run.go

@@ -20,6 +20,11 @@ import (
 	"k8s.io/client-go/rest"
 )
 
+const (
+	imageNameTag     = "quay.io/fntlnz/kubectl-trace-bpftrace:latest"
+	initImageNameTag = "quay.io/dalehamel/kubectl-trace-init"
+)
+
 var (
 	runShort = `Execute a bpftrace program on resources` // Wrap with i18n.T()
 
@@ -35,7 +40,10 @@ var (
   # Run an bpftrace inline program on a pod container
   %[1]s trace run pod/nginx -c nginx -e "tracepoint:syscalls:sys_enter_* { @[probe] = count(); }"
   %[1]s trace run pod/nginx nginx -e "tracepoint:syscalls:sys_enter_* { @[probe] = count(); }"
-  %[1]s trace run pod/nginx nginx -e "tracepoint:syscalls:sys_enter_* { @[probe] = count(); }"`
+  %[1]s trace run pod/nginx nginx -e "tracepoint:syscalls:sys_enter_* { @[probe] = count(); }"
+
+  # Run a bpftrace inline program on a pod container with a custom image for the init container responsible to fetch linux headers 
+  %[1]s trace run pod/nginx nginx -e "tracepoint:syscalls:sys_enter_* { @[probe] = count(); } --init-imagename=quay.io/custom-init-image-name --fetch-headers"`
 
 	runCommand                    = "run"
 	usageString                   = "(POD | TYPE/NAME)"
@@ -58,6 +66,9 @@ type RunOptions struct {
 	eval           string
 	program        string
 	serviceAccount string
+	imageName      string
+	initImageName  string
+	fetchHeaders   bool
 
 	resourceArg string
 	attach      bool
@@ -72,6 +83,10 @@ type RunOptions struct {
 func NewRunOptions(streams genericclioptions.IOStreams) *RunOptions {
 	return &RunOptions{
 		IOStreams: streams,
+
+		serviceAccount: "default",
+		imageName:      imageNameTag,
+		initImageName:  initImageNameTag,
 	}
 }
 
@@ -102,9 +117,12 @@ func NewRunCommand(factory factory.Factory, streams genericclioptions.IOStreams)
 
 	cmd.Flags().StringVarP(&o.container, "container", "c", o.container, "Specify the container")
 	cmd.Flags().BoolVarP(&o.attach, "attach", "a", o.attach, "Wheter or not to attach to the trace program once it is created")
-	cmd.Flags().StringVarP(&o.eval, "eval", "e", "", "Literal string to be evaluated as a bpftrace program")
-	cmd.Flags().StringVarP(&o.program, "filename", "f", "", "File containing a bpftrace program")
-	cmd.Flags().StringVar(&o.serviceAccount, "serviceaccount", "default", "Service account to use to set in the pod spec of the kubectl-trace job")
+	cmd.Flags().StringVarP(&o.eval, "eval", "e", o.eval, "Literal string to be evaluated as a bpftrace program")
+	cmd.Flags().StringVarP(&o.program, "filename", "f", o.program, "File containing a bpftrace program")
+	cmd.Flags().StringVar(&o.serviceAccount, "serviceaccount", o.serviceAccount, "Service account to use to set in the pod spec of the kubectl-trace job")
+	cmd.Flags().StringVar(&o.imageName, "imagename", o.imageName, "Custom image for the tracerunner")
+	cmd.Flags().StringVar(&o.initImageName, "init-imagename", o.initImageName, "Custom image for the init container responsible to fetch and prepare linux headers")
+	cmd.Flags().BoolVar(&o.fetchHeaders, "fetch-headers", o.fetchHeaders, "Wheter to fetch linux headers or not")
 
 	return cmd
 }
@@ -276,6 +294,10 @@ func (o *RunOptions) Run() error {
 		PodUID:         o.podUID,
 		ContainerName:  o.container,
 		IsPod:          o.isPod,
+		// todo(dalehamel) > following fields to be used for #48
+		ImageNameTag:     o.imageName,
+		InitImageNameTag: o.initImageName,
+		FetchHeaders:     o.fetchHeaders,
 	}
 
 	job, err := tc.CreateJob(tj)

pkg/tracejob/job.go

@@ -2,18 +2,15 @@ package tracejob
 
 import (
 	"fmt"
-
-	"github.com/iovisor/kubectl-trace/pkg/version"
-
 	"io"
 	"io/ioutil"
 
 	"github.com/iovisor/kubectl-trace/pkg/meta"
 	batchv1 "k8s.io/api/batch/v1"
 	apiv1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/api/resource"
 	batchv1typed "k8s.io/client-go/kubernetes/typed/batch/v1"
 	corev1typed "k8s.io/client-go/kubernetes/typed/core/v1"
 )
@@ -24,16 +21,20 @@ type TraceJobClient struct {
 	outStream    io.Writer
 }
 
+// TraceJob is a container of info needed to create the job responsible for tracing.
 type TraceJob struct {
-	Name           string
-	ID             types.UID
-	Namespace      string
-	ServiceAccount string
-	Hostname       string
-	Program        string
-	PodUID         string
-	ContainerName  string
-	IsPod          bool
+	Name             string
+	ID               types.UID
+	Namespace        string
+	ServiceAccount   string
+	Hostname         string
+	Program          string
+	PodUID           string
+	ContainerName    string
+	IsPod            bool
+	ImageNameTag     string
+	InitImageNameTag string
+	FetchHeaders     bool
 }
 
 // WithOutStream setup a file stream to output trace job operation information
@@ -252,19 +253,19 @@ func (t *TraceJobClient) CreateJob(nj TraceJob) (*batchv1.Job, error) {
 					Containers: []apiv1.Container{
 						apiv1.Container{
 							Name:    nj.Name,
-							Image:   version.ImageNameTag(),
+							Image:   nj.ImageNameTag,
 							Command: bpfTraceCmd,
 							TTY:     true,
 							Stdin:   true,
 							Resources: apiv1.ResourceRequirements{
-							        Requests: apiv1.ResourceList{
-							                apiv1.ResourceCPU:    resource.MustParse("100m"),
-							                apiv1.ResourceMemory: resource.MustParse("100Mi"),
-							        },
-							        Limits: apiv1.ResourceList{
-							                apiv1.ResourceCPU:    resource.MustParse("1"),
-							                apiv1.ResourceMemory: resource.MustParse("1G"),
-							        },
+								Requests: apiv1.ResourceList{
+									apiv1.ResourceCPU:    resource.MustParse("100m"),
+									apiv1.ResourceMemory: resource.MustParse("100Mi"),
+								},
+								Limits: apiv1.ResourceList{
+									apiv1.ResourceCPU:    resource.MustParse("1"),
+									apiv1.ResourceMemory: resource.MustParse("1G"),
+								},
 							},
 							VolumeMounts: []apiv1.VolumeMount{
 								apiv1.VolumeMount{