feat(push): --platform flag to push a specific platform of a multi-platform image

cmd/uncloud/image/push.go

@@ -4,8 +4,10 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/containerd/platforms"
 	"github.com/docker/compose/v2/pkg/progress"
 	"github.com/psviderski/uncloud/internal/cli"
+	"github.com/psviderski/uncloud/pkg/client"
 	"github.com/spf13/cobra"
 )
 
@@ -13,6 +15,7 @@ type pushOptions struct {
 	image    string
 	machines []string
 	context  string
+	platform string
 }
 
 func NewPushCommand() *cobra.Command {
@@ -30,7 +33,10 @@ The image is uploaded to the machine which CLI is connected to (default) or the
   uc image push myapp:latest -m machine1
 
   # Push image to multiple machines.
-  uc image push myapp:latest -m machine1,machine2,machine3`,
+  uc image push myapp:latest -m machine1,machine2,machine3
+
+  # Push a specific platform of a multi-platform image.
+  uc image push myapp:latest --platform linux/amd64`,
 		Args: cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			uncli := cmd.Context().Value("cli").(*cli.CLI)
@@ -43,6 +49,11 @@ The image is uploaded to the machine which CLI is connected to (default) or the
 	cmd.Flags().StringSliceVarP(&opts.machines, "machine", "m", nil,
 		"Machine names to push the image to. Can be specified multiple times or as a comma-separated "+
 			"list of machine names. (default is connected machine)")
+	cmd.Flags().StringVar(
+		&opts.platform, "platform", "",
+		"Push a specific platform of a multi-platform image (e.g., linux/amd64, linux/arm64).\n"+
+			"Local Docker must be configured to use containerd image store to support multi-platform images.",
+	)
 	cmd.Flags().StringVarP(
 		&opts.context, "context", "c", "",
 		"Name of the cluster context. (default is the current context)",
@@ -52,16 +63,27 @@ The image is uploaded to the machine which CLI is connected to (default) or the
 }
 
 func push(ctx context.Context, uncli *cli.CLI, opts pushOptions) error {
-	client, err := uncli.ConnectCluster(ctx, opts.context)
+	clusterClient, err := uncli.ConnectCluster(ctx, opts.context)
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}
-	defer client.Close()
+	defer clusterClient.Close()
 
 	machines := cli.ExpandCommaSeparatedValues(opts.machines)
+	pushOpts := client.PushImageOptions{
+		Machines: machines,
+	}
+
+	if opts.platform != "" {
+		p, err := platforms.Parse(opts.platform)
+		if err != nil {
+			return fmt.Errorf("invalid platform '%s': %w", opts.platform, err)
+		}
+		pushOpts.Platform = &p
+	}
 
 	return progress.RunWithTitle(ctx, func(ctx context.Context) error {
-		if err = client.PushImage(ctx, opts.image, machines); err != nil {
+		if err = clusterClient.PushImage(ctx, opts.image, pushOpts); err != nil {
 			return fmt.Errorf("push image to cluster: %w", err)
 		}
 		return nil

pkg/api/volume.go

@@ -248,7 +248,7 @@ type VolumeFilter struct {
 	Driver string
 	// Labels filters volumes by label key-value pairs. Volumes must match all labels.
 	Labels map[string]string
-	// MachineIDs filters volumes to those on the specified machines (names or IDs).
+	// Machines filters volumes to those on the specified machines (names or IDs).
 	Machines []string
 	// Names filters volumes by name. Volumes must match one of the names.
 	Names []string

pkg/client/image.go

@@ -17,6 +17,7 @@ import (
 	dockerclient "github.com/docker/docker/client"
 	"github.com/docker/docker/pkg/jsonmessage"
 	"github.com/docker/go-connections/nat"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/psviderski/uncloud/internal/docker"
 	"github.com/psviderski/uncloud/internal/machine/api/pb"
 	"github.com/psviderski/uncloud/internal/machine/constants"
@@ -40,9 +41,18 @@ func (cli *Client) InspectRemoteImage(ctx context.Context, id string) ([]api.Mac
 	return cli.Docker.InspectRemoteImage(ctx, id)
 }
 
+type PushImageOptions struct {
+	// Machines is a list of machine names or IDs to push the image to. If empty, pushes to the machine
+	// the client is connected to.
+	Machines []string
+	// Platform to push for a multi-platform image. Local Docker must use containerd image store
+	// to support multi-platform images.
+	Platform *ocispec.Platform
+}
+
 // PushImage pushes a local Docker image to the specified machines. If no machines are specified,
 // it pushes to the machine the client is connected to.
-func (cli *Client) PushImage(ctx context.Context, image string, machineNamesOrIDs []string) error {
+func (cli *Client) PushImage(ctx context.Context, image string, opts PushImageOptions) error {
 	dockerCliWrapped, err := dockerclient.NewClientWithOpts(dockerclient.FromEnv,
 		dockerclient.WithAPIVersionNegotiation())
 	if err != nil {
@@ -61,18 +71,18 @@ func (cli *Client) PushImage(ctx context.Context, image string, machineNamesOrID
 
 	// Get the machine info for the specified machines or the connected machine if none are specified.
 	var machines []*pb.MachineInfo
-	if len(machineNamesOrIDs) > 0 {
+	if len(opts.Machines) > 0 {
 		machineMembers, err := cli.ListMachines(ctx, &api.MachineFilter{
-			NamesOrIDs: machineNamesOrIDs,
+			NamesOrIDs: opts.Machines,
 		})
 		if err != nil {
 			return fmt.Errorf("list machines: %w", err)
 		}
 
 		// Check if all specified machines were found.
-		if len(machineMembers) != len(machineNamesOrIDs) {
+		if len(machineMembers) != len(opts.Machines) {
 			var notFound []string
-			for _, nameOrID := range machineNamesOrIDs {
+			for _, nameOrID := range opts.Machines {
 				if machineMembers.FindByNameOrID(nameOrID) == nil {
 					notFound = append(notFound, nameOrID)
 				}
@@ -109,7 +119,7 @@ func (cli *Client) PushImage(ctx context.Context, image string, machineNamesOrID
 	//  platforms differ.
 	for _, m := range machines {
 		wg.Go(func() {
-			if err := cli.pushImageToMachine(ctx, dockerCli, image, m); err != nil {
+			if err := cli.pushImageToMachine(ctx, dockerCli, image, m, opts.Platform); err != nil {
 				errCh <- fmt.Errorf("push image to machine '%s': %w", m.Name, err)
 			}
 		})
@@ -128,7 +138,11 @@ func (cli *Client) PushImage(ctx context.Context, image string, machineNamesOrID
 
 // pushImageToMachine pushes a local Docker image to a specific machine using local port forwarding to its unregistry.
 func (cli *Client) pushImageToMachine(
-	ctx context.Context, dockerCli *docker.Client, imageName string, machine *pb.MachineInfo,
+	ctx context.Context,
+	dockerCli *docker.Client,
+	imageName string,
+	machine *pb.MachineInfo,
+	platform *ocispec.Platform,
 ) error {
 	pw := progress.ContextWriter(ctx)
 
@@ -216,7 +230,9 @@ func (cli *Client) pushImageToMachine(
 	pushEventID := fmt.Sprintf("Pushing %s to %s", boldStyle.Render(imageName), boldStyle.Render(machine.Name))
 	pw.Event(progress.NewEvent(pushEventID, progress.Working, "Pushing"))
 
-	pushCh, err := dockerCli.PushImage(ctx, pushImageTag, image.PushOptions{})
+	pushCh, err := dockerCli.PushImage(ctx, pushImageTag, image.PushOptions{
+		Platform: platform,
+	})
 	if err != nil {
 		pw.Event(progress.NewEvent(pushEventID, progress.Error, err.Error()))
 		return fmt.Errorf("push image: %w", err)