orchard create vm: support --image-pull-policy=Always (#110)

internal/command/create/vm.go

@@ -22,6 +22,7 @@ var resources map[string]string
 var restartPolicy string
 var startupScript string
 var hostDirsRaw []string
+var imagePullPolicy string
 
 func newCreateVMCommand() *cobra.Command {
 	command := &cobra.Command{
@@ -39,15 +40,19 @@ func newCreateVMCommand() *cobra.Command {
 	command.PersistentFlags().BoolVar(&headless, "headless", true, "whether to run without graphics")
 	command.PersistentFlags().StringToStringVar(&resources, "resources", map[string]string{},
 		"resources to request for this VM")
-	command.PersistentFlags().StringVar(&restartPolicy, "restart-policy", "Never",
-		"restart policy for this VM: specify \"Never\" to never restart or \"OnFailure\" "+
-			"to only restart when the VM fails")
+	command.PersistentFlags().StringVar(&restartPolicy, "restart-policy", string(v1.RestartPolicyNever),
+		fmt.Sprintf("restart policy for this VM: specify %q to never restart or %q "+
+			"to only restart when the VM fails", v1.RestartPolicyNever, v1.RestartPolicyOnFailure))
 	command.PersistentFlags().StringVar(&startupScript, "startup-script", "",
 		"startup script (e.g. --startup-script=\"sync\") or a path to a script file prefixed with \"@\" "+
 			"(e.g. \"--startup-script=@script.sh\")")
 	command.PersistentFlags().StringSliceVar(&hostDirsRaw, "host-dirs", []string{},
 		"host directories to mount to the VM, can be specified multiple times and/or be comma-separated "+
 			"(see \"tart run\"'s --dir argument for syntax)")
+	command.PersistentFlags().StringVar(&imagePullPolicy, "image-pull-policy", string(v1.ImagePullPolicyIfNotPresent),
+		fmt.Sprintf("image pull policy for this VM, by default the image is only only pulled if it doesn't "+
+			"exist in the cache (%q), specify %q to always try to pull the image",
+			v1.ImagePullPolicyIfNotPresent, v1.ImagePullPolicyAlways))
 
 	return command
 }
@@ -88,6 +93,12 @@ func runCreateVM(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("%w: %v", ErrVMFailed, err)
 	}
 
+	// Convert image pull policy
+	vm.ImagePullPolicy, err = v1.NewImagePullPolicyFromString(imagePullPolicy)
+	if err != nil {
+		return fmt.Errorf("%w: %v", ErrVMFailed, err)
+	}
+
 	// Convert restart policy
 	vm.RestartPolicy, err = v1.NewRestartPolicyFromString(restartPolicy)
 	if err != nil {

internal/command/get/cluster_settings.go

@@ -39,10 +39,7 @@ func runGetClusterSettings(cmd *cobra.Command, args []string) error {
 		return policy.String()
 	})
 	hostDirPoliciesDescription := strings.Join(hostDirPoliciesAsStrings, ",")
-	if hostDirPoliciesDescription == "" {
-		hostDirPoliciesDescription = "none"
-	}
-	table.AddRow("hostDir policies", hostDirPoliciesDescription)
+	table.AddRow("hostDir policies", nonEmptyOrNone(hostDirPoliciesDescription))
 
 	fmt.Println(table)
 

internal/command/get/get.go

@@ -17,7 +17,16 @@ func NewCommand() *cobra.Command {
 		newGetBootstrapTokenCommand(),
 		newGetClusterSettingsCommand(),
 		newGetServiceAccountCommand(),
+		newGetVMCommand(),
 	)
 
 	return command
 }
+
+func nonEmptyOrNone(s string) string {
+	if s != "" {
+		return s
+	}
+
+	return "none"
+}

internal/command/get/vm.go

@@ -0,0 +1,106 @@
+package get
+
+import (
+	"fmt"
+	"github.com/cirruslabs/orchard/internal/structpath"
+	"github.com/cirruslabs/orchard/pkg/client"
+	v1 "github.com/cirruslabs/orchard/pkg/resource/v1"
+	"github.com/dustin/go-humanize"
+	"github.com/gosuri/uitable"
+	"github.com/samber/lo"
+	"github.com/spf13/cobra"
+	"strings"
+	"time"
+)
+
+func newGetVMCommand() *cobra.Command {
+	command := &cobra.Command{
+		Use:   "vm NAME",
+		Short: "Retrieve a VM and it's fields",
+		RunE:  runGetVM,
+		Args:  cobra.ExactArgs(1),
+	}
+
+	return command
+}
+
+func runGetVM(cmd *cobra.Command, args []string) error {
+	name := args[0]
+
+	client, err := client.New()
+	if err != nil {
+		return err
+	}
+
+	// Ability to retrieve resource fields (e.g. "orchard get vm macos/status")
+	splits := strings.Split(name, "/")
+	var path []string
+	if len(splits) > 1 {
+		name = splits[0]
+		path = splits[1:]
+	}
+
+	vm, err := client.VMs().Get(cmd.Context(), name)
+	if err != nil {
+		return err
+	}
+
+	// Ability to retrieve resource fields (e.g. "orchard get vm macos/status")
+	if len(path) != 0 {
+		result, ok := structpath.Lookup(*vm, path)
+		if !ok {
+			return fmt.Errorf("%w: failed to find the specified field \"%s\" or the field is not a string",
+				ErrGetFailed, strings.Join(path, "/"))
+		}
+
+		fmt.Println(result)
+
+		return nil
+	}
+
+	table := uitable.New()
+
+	table.AddRow("Name", vm.Name)
+	createdAtInfo := humanize.RelTime(vm.CreatedAt, time.Now(), "ago", "in the future")
+	table.AddRow("Created", createdAtInfo)
+	table.AddRow("Image", vm.Image)
+	table.AddRow("Image pull policy", vm.ImagePullPolicy)
+	table.AddRow("CPU", vm.CPU)
+	table.AddRow("Memory", vm.Memory)
+	table.AddRow("Softnet enabled", vm.NetSoftnet)
+	table.AddRow("Bridged networking interface", nonEmptyOrNone(vm.NetBridged))
+	table.AddRow("Headless mode", vm.Headless)
+	table.AddRow("Status", vm.Status)
+	table.AddRow("Status message", vm.StatusMessage)
+	table.AddRow("Assigned worker", nonEmptyOrNone(vm.Worker))
+
+	table.AddRow("Restart policy", vm.RestartPolicy)
+	restartedAtInfo := "never"
+	if !vm.RestartedAt.IsZero() {
+		restartedAtInfo = humanize.RelTime(vm.RestartedAt, time.Now(), "ago", "in the future")
+	}
+	table.AddRow("Restarted", restartedAtInfo)
+	table.AddRow("Restart count", vm.RestartCount)
+
+	var resourcesInfo string
+	if len(vm.Resources) != 0 {
+		resourceDescriptions := lo.MapToSlice(vm.Resources, func(key string, value uint64) string {
+			return fmt.Sprintf("%s: %d", key, value)
+		})
+		resourcesInfo = strings.Join(resourceDescriptions, "\n")
+	}
+	table.AddRow("Resources", nonEmptyOrNone(resourcesInfo))
+
+	var hostDirsInfo string
+	if len(vm.HostDirs) != 0 {
+		hostDirsDescriptions := lo.Map(vm.HostDirs, func(hostDir v1.HostDir, index int) string {
+			return hostDir.String()
+		})
+		hostDirsInfo = strings.Join(hostDirsDescriptions, "\n")
+	}
+	table.AddRow("Host directories", nonEmptyOrNone(hostDirsInfo))
+
+	fmt.Println(table)
+
+	return nil
+}

internal/controller/api_vms.go

@@ -50,6 +50,16 @@ func (controller *Controller) createVM(ctx *gin.Context) responder.Responder {
 		vm.Resources[v1.ResourceTartVMs] = 1
 	}
 
+	// Validate image pull policy and provide a default value if it's missing
+	if vm.ImagePullPolicy != "" {
+		if _, err := v1.NewImagePullPolicyFromString(string(vm.ImagePullPolicy)); err != nil {
+			return responder.JSON(http.StatusPreconditionFailed,
+				NewErrorResponse("unsupported image pull policy: %q", vm.ImagePullPolicy))
+		}
+	} else {
+		vm.ImagePullPolicy = v1.ImagePullPolicyIfNotPresent
+	}
+
 	// Validate restart policy and provide a default value if it's missing
 	if vm.RestartPolicy != "" {
 		if _, err := v1.NewRestartPolicyFromString(string(vm.RestartPolicy)); err != nil {

internal/structpath/structpath.go

@@ -1,6 +1,7 @@
 package structpath
 
 import (
+	"fmt"
 	"reflect"
 	"strings"
 )
@@ -23,9 +24,14 @@ func Lookup(target interface{}, path []string) (s string, ok bool) {
 	}
 
 	result, ok := currentValue.Interface().(string)
-	if !ok {
-		return "", false
+	if ok {
+		return result, true
 	}
 
-	return result, true
+	stringerResult, ok := currentValue.Interface().(fmt.Stringer)
+	if ok {
+		return stringerResult.String(), true
+	}
+
+	return "", false
 }

internal/worker/vmmanager/vm.go

@@ -59,11 +59,22 @@ func NewVM(
 		wg: &sync.WaitGroup{},
 	}
 
-	// Clone the VM so `run` and `ip` are not racing
+	// Optionally pull and clone the VM so that `run` and `ip` will not be racing
 	vm.logger.Debugf("creating VM")
 
+	if vmResource.ImagePullPolicy == v1.ImagePullPolicyAlways {
+		_, _, err := tart.Tart(ctx, vm.logger, "pull", vm.Resource.Image)
+		if err != nil {
+			vm.setErr(fmt.Errorf("failed to pull the VM: %w", err))
+
+			return vm, nil
+		}
+	}
+
 	if err := vm.cloneAndConfigure(ctx); err != nil {
-		return nil, fmt.Errorf("failed to clone the VM: %w", err)
+		vm.setErr(fmt.Errorf("failed to clone the VM: %w", err))
+
+		return vm, nil
 	}
 
 	vm.wg.Add(1)

pkg/resource/v1/image_pull_policy.go

@@ -0,0 +1,26 @@
+package v1
+
+import (
+	"errors"
+	"fmt"
+)
+
+var ErrInvalidImagePullPolicy = errors.New("invalid image pull policy")
+
+type ImagePullPolicy string
+
+const (
+	ImagePullPolicyIfNotPresent ImagePullPolicy = "IfNotPresent"
+	ImagePullPolicyAlways       ImagePullPolicy = "Always"
+)
+
+func NewImagePullPolicyFromString(s string) (ImagePullPolicy, error) {
+	switch s {
+	case string(ImagePullPolicyIfNotPresent):
+		return ImagePullPolicyIfNotPresent, nil
+	case string(ImagePullPolicyAlways):
+		return ImagePullPolicyAlways, nil
+	default:
+		return "", fmt.Errorf("%w %q", ErrInvalidImagePullPolicy, s)
+	}
+}

pkg/resource/v1/v1.go

@@ -19,12 +19,13 @@ type Meta struct {
 }
 
 type VM struct {
-	Image      string `json:"image"`
-	CPU        uint64 `json:"cpu"`
-	Memory     uint64 `json:"memory"`
-	NetSoftnet bool   `json:"net-softnet"`
-	NetBridged string `json:"net-bridged"`
-	Headless   bool   `json:"headless"`
+	Image           string          `json:"image"`
+	ImagePullPolicy ImagePullPolicy `json:"imagePullPolicy"`
+	CPU             uint64          `json:"cpu"`
+	Memory          uint64          `json:"memory"`
+	NetSoftnet      bool            `json:"net-softnet"`
+	NetBridged      string          `json:"net-bridged"`
+	Headless        bool            `json:"headless"`
 
 	// Status field is used to track the lifecycle of the VM associated with this resource.
 	Status        VMStatus `json:"status"`
@@ -78,6 +79,10 @@ func (vm VM) TerminalState() bool {
 
 type VMStatus string
 
+func (vmStatus VMStatus) String() string {
+	return string(vmStatus)
+}
+
 const (
 	// VMStatusPending is set by the Controller for all newly-created VM resources.
 	VMStatusPending VMStatus = "pending"