Do not use the Storage/Client in ignite-spawn

cmd/ignite-spawn/ignite-spawn.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/weaveworks/ignite/cmd/ignite/cmd/cmdutil"
 	api "github.com/weaveworks/ignite/pkg/apis/ignite"
+	"github.com/weaveworks/ignite/pkg/apis/ignite/scheme"
 	meta "github.com/weaveworks/ignite/pkg/apis/meta/v1alpha1"
 	"github.com/weaveworks/ignite/pkg/constants"
 	"github.com/weaveworks/ignite/pkg/container"
@@ -24,7 +25,22 @@ func main() {
 	RunIgniteSpawn()
 }
 
-func StartVM(co *options) error {
+func decodeVM(vmID string) (*api.VM, error) {
+	filePath := constants.IGNITE_SPAWN_VM_FILE_PATH
+	obj, err := scheme.Serializer.DecodeFile(filePath, true)
+	if err != nil {
+		return nil, err
+	}
+	vm, ok := obj.(*api.VM)
+	if !ok {
+		return nil, fmt.Errorf("object couldn't be converted to VM")
+	}
+	// Explicitely set the GVK on this object
+	vm.SetGroupVersionKind(api.SchemeGroupVersion.WithKind(api.KindVM.Title()))
+	return vm, nil
+}
+
+func StartVM(vm *api.VM) error {
 	// Setup networking inside of the container, return the available interfaces
 	dhcpIfaces, err := container.SetupContainerNetworking()
 	if err != nil {
@@ -34,61 +50,61 @@ func StartVM(co *options) error {
 	// Serve DHCP requests for those interfaces
 	// This function returns the available IP addresses that are being
 	// served over DHCP now
-	ipAddrs, err := container.StartDHCPServers(co.vm, dhcpIfaces)
+	ipAddrs, err := container.StartDHCPServers(vm, dhcpIfaces)
 	if err != nil {
 		return err
 	}
 
 	// Serve metrics over an unix socket in the VM's own directory
-	metricsSocket := path.Join(co.vm.ObjectPath(), constants.PROMETHEUS_SOCKET)
+	metricsSocket := path.Join(vm.ObjectPath(), constants.PROMETHEUS_SOCKET)
 	go prometheus.ServeMetrics(metricsSocket)
 
 	// Update the VM status and IP address information
-	if err := patchRunning(co.vm, ipAddrs); err != nil {
+	if err := patchRunning(vm, ipAddrs); err != nil {
 		return fmt.Errorf("failed to patch VM state: %v", err)
 	}
 
 	// Patches the VM object to set state to stopped, and clear IP addresses
-	defer patchStopped(co.vm)
+	defer patchStopped(vm)
 
 	// Remove the snapshot overlay post-run, which also removes the detached backing loop devices
-	defer dmlegacy.DeactivateSnapshot(co.vm)
+	defer dmlegacy.DeactivateSnapshot(vm)
 
 	// Remove the Prometheus socket post-run
 	defer os.Remove(metricsSocket)
 
 	// Execute Firecracker
-	if err := container.ExecuteFirecracker(co.vm, dhcpIfaces); err != nil {
-		return fmt.Errorf("runtime error for VM %q: %v", co.vm.GetUID(), err)
+	if err := container.ExecuteFirecracker(vm, dhcpIfaces); err != nil {
+		return fmt.Errorf("runtime error for VM %q: %v", vm.GetUID(), err)
 	}
 
 	return nil
 }
 
 func patchRunning(vm *api.VM, ipAddrs []net.IP) error {
-	patch, err := patchutil.Create(vm, func(obj meta.Object) error {
-		patchVM := obj.(*api.VM)
+	return patchVM(vm, func(patchVM *api.VM) error {
 		patchVM.Status.State = api.VMStateRunning
 		patchVM.Status.IPAddresses = ipAddrs
 		return nil
 	})
-	if err != nil {
-		return err
-	}
-	// Perform the patch
-	return providers.Client.VMs().Patch(vm.GetUID(), patch)
 }
 
 func patchStopped(vm *api.VM) error {
-	patch, err := patchutil.Create(vm, func(obj meta.Object) error {
-		patchVM := obj.(*api.VM)
+	return patchVM(vm, func(patchVM *api.VM) error {
 		patchVM.Status.State = api.VMStateStopped
 		patchVM.Status.IPAddresses = nil
 		return nil
 	})
+}
+
+func patchVM(vm *api.VM, fn func(*api.VM) error) error {
+	patch, err := patchutil.Create(vm, func(obj meta.Object) error {
+		patchVM := obj.(*api.VM)
+		return fn(patchVM)
+	})
 	if err != nil {
 		return err
 	}
 	// Perform the patch
-	return providers.Client.VMs().Patch(vm.GetUID(), patch)
+	return patchutil.ApplyOnFile(constants.IGNITE_SPAWN_VM_FILE_PATH, patch, vm.GroupVersionKind())
 }

cmd/ignite-spawn/root.go

@@ -27,12 +27,12 @@ func RunIgniteSpawn() {
 	}
 
 	cmdutil.CheckErr(func() error {
-		opts, err := NewOptions(fs.Args()[0])
+		vm, err := decodeVM(fs.Args()[0])
 		if err != nil {
 			return err
 		}
 
-		return StartVM(opts)
+		return StartVM(vm)
 	}())
 }
 

pkg/constants/vm.go

@@ -18,4 +18,7 @@ const (
 
 	// Prometheus socket filename
 	PROMETHEUS_SOCKET = "prometheus.sock"
+
+	// Where the VM specification is located inside of the container
+	IGNITE_SPAWN_VM_FILE_PATH = "/vm.json"
 )

pkg/operations/start.go

@@ -2,7 +2,6 @@ package operations
 
 import (
 	"fmt"
-	"github.com/weaveworks/ignite/pkg/logs"
 	"io"
 	"io/ioutil"
 	"path"
@@ -11,14 +10,13 @@ import (
 
 	log "github.com/sirupsen/logrus"
 	api "github.com/weaveworks/ignite/pkg/apis/ignite"
-	meta "github.com/weaveworks/ignite/pkg/apis/meta/v1alpha1"
 	"github.com/weaveworks/ignite/pkg/constants"
 	"github.com/weaveworks/ignite/pkg/dmlegacy"
+	"github.com/weaveworks/ignite/pkg/logs"
 	"github.com/weaveworks/ignite/pkg/operations/lookup"
 	"github.com/weaveworks/ignite/pkg/providers"
 	"github.com/weaveworks/ignite/pkg/runtime"
 	"github.com/weaveworks/ignite/pkg/util"
-	patchutil "github.com/weaveworks/ignite/pkg/util/patch"
 	"github.com/weaveworks/ignite/pkg/version"
 )
 
@@ -49,7 +47,7 @@ func StartVM(vm *api.VM, debug bool) error {
 	}
 
 	config := &runtime.ContainerConfig{
-		Cmd:    []string{vm.GetUID().String(), "--log-level", logs.Logger.Level.String()},
+		Cmd:    []string{fmt.Sprintf("--log-level=%s", logs.Logger.Level.String()), vm.GetUID().String()},
 		Labels: map[string]string{"ignite.name": vm.GetName()},
 		Binds: []*runtime.Bind{
 			{
@@ -60,6 +58,11 @@ func StartVM(vm *api.VM, debug bool) error {
 				HostPath:      kernelDir,
 				ContainerPath: kernelDir,
 			},
+			{
+				// Mount the metadata.json file specifically into the container, to a well-known place for ignite-spawn to access
+				HostPath:      path.Join(vmDir, constants.METADATA),
+				ContainerPath: constants.IGNITE_SPAWN_VM_FILE_PATH,
+			},
 		},
 		CapAdds: []string{
 			"SYS_ADMIN", // Needed to run "dmsetup remove" inside the container
@@ -103,20 +106,6 @@ func StartVM(vm *api.VM, debug bool) error {
 
 	log.Infof("Started Firecracker VM %q in a container with ID %q", vm.GetUID(), containerID)
 
-	// Set an annotation on the VM object with the containerID for now
-	patch, err := patchutil.Create(vm, func(obj meta.Object) error {
-		patchVM := obj.(*api.VM)
-		patchVM.SetAnnotation("v1alpha1.ignite.weave.works.containerID", containerID)
-		return nil
-	})
-	if err != nil {
-		return err
-	}
-	// Perform the patch
-	if err := providers.Client.VMs().Patch(vm.GetUID(), patch); err != nil {
-		return err
-	}
-
 	// TODO: Follow-up the container here with a defer, or dedicated goroutine. We should output
 	// if it started successfully or not
 	// TODO: This is temporary until we have proper communication to the container

pkg/util/patch/patch.go

@@ -2,6 +2,7 @@ package patch
 
 import (
 	"fmt"
+	"io/ioutil"
 
 	"github.com/weaveworks/ignite/pkg/apis/ignite/scheme"
 	meta "github.com/weaveworks/ignite/pkg/apis/meta/v1alpha1"
@@ -52,3 +53,17 @@ func Apply(original, patch []byte, gvk schema.GroupVersionKind) ([]byte, error)
 
 	return strategicpatch.StrategicMergePatch(original, patch, emptyobj)
 }
+
+func ApplyOnFile(filePath string, patch []byte, gvk schema.GroupVersionKind) error {
+	oldContent, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		return err
+	}
+
+	newContent, err := Apply(oldContent, patch, gvk)
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(filePath, newContent, 0644)
+}