feat(pkg/cmd): run command

Author: leodido

pkg/cmd/run.go

@@ -0,0 +1,135 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/fntlnz/kubectl-trace/factory"
+	"github.com/spf13/cobra"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	// "k8s.io/kubernetes/pkg/kubectl/util/templates"
+)
+
+var (
+	runShort = `Execute a bpftrace program on resources` // Wrap with i18n.T()
+
+	runLong = runShort
+
+	runExamples = `
+  # Count system calls using tracepoints on a specific node
+  %[1]s trace run node/kubernetes-node-emt8.c.myproject.internal -e 'kprobe:do_sys_open { printf("%s: %s\n", comm, str(arg1)) }'
+
+  # Execute a bpftrace program from file on a specific node
+  %[1]s trace run node/kubernetes-node-emt8.c.myproject.internal -p read.bt
+
+  # 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(); }"`
+
+	runCommand                    = "run"
+	usageString                   = "(POD | TYPE/NAME)"
+	requiredArgErrString          = fmt.Sprintf("%s is a required argument for the %s command", usageString, runCommand)
+	containerAsArgOrFlagErrString = "specify container inline as argument or via its flag"
+	bpftraceMissingErrString      = "the bpftrace program is mandatory"
+)
+
+// RunOptions ...
+type RunOptions struct {
+	genericclioptions.IOStreams
+
+	namespace string
+
+	// Local to this command
+	container   string
+	eval        string
+	program     string
+	resourceArg string
+}
+
+// NewRunOptions provides an instance of RunOptions with default values.
+func NewRunOptions(streams genericclioptions.IOStreams) *RunOptions {
+	return &RunOptions{
+		IOStreams: streams,
+	}
+}
+
+// NewRunCommand provides the run command wrapping RunOptions.
+func NewRunCommand(factory factory.Factory, streams genericclioptions.IOStreams) *cobra.Command {
+	o := NewRunOptions(streams)
+
+	cmd := &cobra.Command{
+		Use:          fmt.Sprintf("%s %s [-c CONTAINER]", runCommand, usageString),
+		Short:        runShort,
+		Long:         runLong,                             // Wrap with templates.LongDesc()
+		Example:      fmt.Sprintf(runExamples, "kubectl"), // Wrap with templates.Examples()
+		SilenceUsage: true,
+		PreRunE: func(c *cobra.Command, args []string) error {
+			return o.Validate(c, args)
+		},
+		RunE: func(c *cobra.Command, args []string) error {
+			if err := o.Complete(factory, c, args); err != nil {
+				return err
+			}
+			return nil
+		},
+	}
+
+	cmd.Flags().StringVarP(&o.container, "container", "c", o.container, "Specify the container")
+	cmd.Flags().StringVarP(&o.eval, "eval", "e", "", "Literal string to be evaluated as a bpftrace program")
+	cmd.Flags().StringVarP(&o.program, "program", "p", "", "File containing a bpftrace program")
+
+	return cmd
+}
+
+// Validate validates the arguments and flags populating RunOptions accordingly.
+func (o *RunOptions) Validate(cmd *cobra.Command, args []string) error {
+	containerDefined := cmd.Flag("container").Changed
+	switch len(args) {
+	case 1:
+		o.resourceArg = args[0]
+		if !containerDefined {
+			return fmt.Errorf(containerAsArgOrFlagErrString)
+		}
+		break
+	// 2nd argument interpreted as container when provided
+	case 2:
+		o.resourceArg = args[0]
+		o.container = args[1]
+		if containerDefined {
+			return fmt.Errorf(containerAsArgOrFlagErrString)
+		}
+		break
+	default:
+		return fmt.Errorf(requiredArgErrString)
+	}
+
+	if !cmd.Flag("eval").Changed && !cmd.Flag("program").Changed {
+		return fmt.Errorf(bpftraceMissingErrString)
+	}
+
+	// todo > complete validation
+	// - make errors
+	// - make validators
+	if len(o.container) == 0 {
+		return fmt.Errorf("invalid container")
+	}
+	// if len(o.eval) == 0 || file not exist(o.program) || file is empty(o.program) {
+	// 	return fmt.Errorf("invalid bpftrace program")
+	// }
+
+	return nil
+}
+
+// Complete completes the setup of the command.
+func (o *RunOptions) Complete(factory factory.Factory, cmd *cobra.Command, args []string) error {
+	spew.Dump(o)
+
+	o.namespace, _, _ = factory.ToRawKubeConfigLoader().Namespace()
+
+	spew.Dump(o)
+
+	// get resource by pof | type/name
+	// get container
+
+	return nil
+}