Adds basic implementation for Systemd and adds systemd support for kraft run cmd

Signed-off-by: MdSahil-oss <mohdssahil1@gmail.com>

Author: MdSahil-oss

go.mod

@@ -39,6 +39,7 @@ require (
 	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510
 	github.com/google/uuid v1.6.0
 	github.com/henvic/httpretty v0.1.3
+	github.com/kardianos/service v1.2.2
 	github.com/kubescape/go-git-url v0.0.30
 	github.com/mattn/go-colorable v0.1.13
 	github.com/mattn/go-isatty v0.0.20
@@ -167,7 +168,6 @@ require (
 	github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/kardianos/service v1.2.2 // indirect
 	github.com/kevinburke/ssh_config v1.2.0 // indirect
 	github.com/klauspost/compress v1.17.4 // indirect
 	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect

internal/cli/kraft/run/run.go

@@ -8,8 +8,12 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
 
 	"github.com/MakeNowJust/heredoc"
+	"github.com/kardianos/service"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	corev1 "k8s.io/api/core/v1"
@@ -19,11 +23,14 @@ import (
 	machineapi "kraftkit.sh/api/machine/v1alpha1"
 	"kraftkit.sh/cmdfactory"
 	"kraftkit.sh/config"
+	"kraftkit.sh/internal/cli/kraft/remove"
 	"kraftkit.sh/internal/cli/kraft/start"
+	"kraftkit.sh/internal/cli/kraft/stop"
 	"kraftkit.sh/internal/set"
 	"kraftkit.sh/iostreams"
 	"kraftkit.sh/log"
 	mplatform "kraftkit.sh/machine/platform"
+	"kraftkit.sh/machine/platform/systemd"
 	"kraftkit.sh/packmanager"
 	"kraftkit.sh/tui/selection"
 	ukarch "kraftkit.sh/unikraft/arch"
@@ -51,6 +58,7 @@ type RunOptions struct {
 	Rootfs        string   `long:"rootfs" usage:"Specify a path to use as root file system (can be volume or initramfs)"`
 	RunAs         string   `long:"as" usage:"Force a specific runner"`
 	Runtime       string   `long:"runtime" short:"r" usage:"Set an alternative unikernel runtime"`
+	Systemd       bool     `long:"systemd" usage:"runs unikernel as systemd process"`
 	Target        string   `long:"target" short:"t" usage:"Explicitly use the defined project target"`
 	Volumes       []string `long:"volume" short:"v" usage:"Bind a volume to the instance"`
 	WithKernelDbg bool     `long:"symbolic" usage:"Use the debuggable (symbolic) unikernel"`
@@ -376,15 +384,71 @@ func (opts *RunOptions) Run(ctx context.Context, args []string) error {
 		return err
 	}
 
-	if opts.NoStart {
+	if opts.NoStart && !opts.Systemd {
 		// Output the name of the instance such that it can be piped
 		fmt.Fprintf(iostreams.G(ctx).Out, "%s\n", machine.Name)
 		return nil
 	}
 
-	return start.Start(ctx, &start.StartOptions{
-		Detach:   opts.Detach,
+	err = start.Start(ctx, &start.StartOptions{
+		Detach:   opts.Systemd || opts.Detach,
 		Platform: opts.platform.String(),
 		Remove:   opts.Remove,
 	}, machine.Name)
+
+	// Installs systemd serivce that runs a new unikernel instance on each start.
+	if err == nil && opts.Systemd {
+		// Stops & removes the created testing instance if that is still runnning & present.
+		if err = stop.Stop(ctx, &stop.StopOptions{Platform: opts.platform.String()}, machine.Name); err != nil {
+			log.G(ctx).Debugf("instance %s was already stopped", machine.Name)
+		}
+		if err = remove.Remove(ctx, &remove.RemoveOptions{Platform: opts.platform.String()}, machine.Name); err != nil {
+			log.G(ctx).Errorf("could not remove %s", machine.Name)
+		}
+
+		opts.Name = machine.Name
+		opts.Remove = true
+		sysdArgs := []string{"run"}
+		sysdArgs = append(sysdArgs, opts.GetArgs()...)
+
+		if len(args) > 0 {
+			if strings.HasPrefix(args[0], ".") {
+				pwd, err := os.Getwd()
+				if err != nil {
+					return err
+				}
+				args[0] = filepath.Join(pwd, args[0])
+			}
+			sysdArgs = append(sysdArgs, args[0])
+		} else {
+			sysdArgs = append(sysdArgs, opts.workdir)
+		}
+
+		svcConfig, err := systemd.NewMachineV1alpha1ServiceSystemdWrapper(
+			ctx,
+			systemd.WithName(machine.Name),
+			systemd.WithDescription("created by Kraftkit"),
+			systemd.WithArguments(sysdArgs),
+			systemd.WithOptions(service.KeyValue{
+				"Restart": "never",
+			}),
+		)
+		if err != nil {
+			return err
+		}
+
+		machine, err = svcConfig.Create(ctx, machine)
+		if err != nil {
+			return err
+		}
+		log.G(ctx).Infof("created a systemd process named %s ", svcConfig.Name)
+
+		_, err = svcConfig.Start(ctx, machine)
+		if err != nil {
+			return err
+		}
+		log.G(ctx).Infof("started running %s as systemd process", svcConfig.Name)
+	}
+
+	return err
 }

internal/cli/kraft/run/utils.go

@@ -459,3 +459,66 @@ func (opts *RunOptions) parseEnvs(_ context.Context, machine *machineapi.Machine
 
 	return nil
 }
+
+// GetArgs returns all the arguments of run command as an array of strings.
+func (opts *RunOptions) GetArgs() []string {
+	args := []string{}
+	if opts.Detach {
+		args = append(args, "--detach")
+	}
+	if opts.DisableAccel {
+		args = append(args, "--disable-acceleration")
+	}
+	if opts.PrefixName {
+		args = append(args, "--prefix-name")
+	}
+	if opts.WithKernelDbg {
+		args = append(args, "--symbolic")
+	}
+	if opts.Remove {
+		args = append(args, "--rm")
+	}
+	if len(opts.Name) > 0 {
+		args = append(args, "--name", opts.Name)
+	}
+	if len(opts.Architecture) > 0 {
+		args = append(args, "--arch", opts.Architecture)
+	}
+	if len(opts.RunAs) > 0 {
+		args = append(args, "--as", opts.RunAs)
+	}
+	if len(opts.KernelArgs) > 0 {
+		args = append(args, "--kernel-arg", strings.Join(opts.KernelArgs, " "))
+	}
+	if len(opts.Kraftfile) > 0 {
+		args = append(args, "--kraftfile", opts.Kraftfile)
+	}
+	if len(opts.MacAddress) > 0 {
+		args = append(args, "--mac", opts.MacAddress)
+	}
+	if len(opts.Memory) > 0 {
+		args = append(args, "--memory", opts.Memory)
+	}
+	if len(opts.Networks) > 0 {
+		args = append(args, "--network", strings.Join(opts.Networks, " "))
+	}
+	if len(opts.Platform) > 0 {
+		args = append(args, "--plat", opts.Platform)
+	}
+	if len(opts.Ports) > 0 {
+		args = append(args, "--port", strings.Join(opts.Ports, " "))
+	}
+	if len(opts.Prefix) > 0 {
+		args = append(args, "--prefix", opts.Prefix)
+	}
+	if len(opts.Rootfs) > 0 {
+		args = append(args, "--rootfs", opts.Rootfs)
+	}
+	if len(opts.Target) > 0 {
+		args = append(args, "--target ", opts.Target)
+	}
+	if len(opts.Volumes) > 0 {
+		args = append(args, "--volume", strings.Join(opts.Volumes, " "))
+	}
+	return args
+}

machine/platform/systemd/manage.go

@@ -9,9 +9,12 @@ func (p *startStop) Start(s service.Service) error {
 	go p.run()
 	return nil
 }
-func (p *startStop) run() {
+
+func (p *startStop) run() error {
 	// Do work here
+	return nil
 }
+
 func (p *startStop) Stop(s service.Service) error {
 	// Stop should not block. Return with a few seconds.
 	return nil

machine/platform/systemd/options.go

@@ -4,42 +4,58 @@ import "github.com/kardianos/service"
 
 type ServiceConfigOption func(*ServiceConfig) error
 
-// WithName sets the name of the systemd process.
+// WithName sets the name of systemd service.
 func WithName(name string) ServiceConfigOption {
 	return func(config *ServiceConfig) error {
-		config.name = name
+		config.Name = name
 		return nil
 	}
 }
 
-// WithDisplayName sets the display-name of the systemd process.
+// WithDisplayName sets the display-name of systemd service.
 func WithDisplayName(dName string) ServiceConfigOption {
 	return func(config *ServiceConfig) error {
-		config.displayName = dName
+		config.DisplayName = dName
 		return nil
 	}
 }
 
-// WithDescription sets the description of the systemd process.
+// WithDescription sets the description/heading of systemd service.
 func WithDescription(desc string) ServiceConfigOption {
 	return func(config *ServiceConfig) error {
-		config.description = desc
+		config.Description = desc
 		return nil
 	}
 }
 
-// WithDependencies sets the dependencies of the systemd process.
+// WithDependencies sets the dependencies of systemd service.
 func WithDependencies(deps []string) ServiceConfigOption {
 	return func(config *ServiceConfig) error {
-		config.dependencies = deps
+		config.Dependencies = deps
 		return nil
 	}
 }
 
-// WithOptions sets the options of the systemd process.
+// WithEnvVars sets the environment variables for systemd service.
+func WithEnvVars(envVars map[string]string) ServiceConfigOption {
+	return func(config *ServiceConfig) error {
+		config.EnvVars = envVars
+		return nil
+	}
+}
+
+// WithArguments sets the arguments to the command executed by systemd service.
+func WithArguments(args []string) ServiceConfigOption {
+	return func(config *ServiceConfig) error {
+		config.Arguments = args
+		return nil
+	}
+}
+
+// WithOptions sets the options of systemd service.
 func WithOptions(opts service.KeyValue) ServiceConfigOption {
 	return func(config *ServiceConfig) error {
-		config.option = opts
+		config.Option = opts
 		return nil
 	}
 }