feat(images): gRPC client and server for ListImages

pkg/api/image.go

@@ -3,6 +3,7 @@ package api
 import (
 	"github.com/distribution/reference"
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/image"
 	v1 "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/psviderski/uncloud/internal/machine/api/pb"
 )
@@ -12,6 +13,23 @@ type MachineImage struct {
 	Image    types.ImageInspect
 }
 
+// MachineImages represents images present on a particular machine.
+type MachineImages struct {
+	Metadata *pb.Metadata
+	// DockerImages is a list of images present in the Docker internal image store.
+	// It may be empty if Docker uses the containerd image store directly (containerd-snapshotter feature).
+	DockerImages []image.Summary
+	// ContainerdImages is a list of images present in the containerd image store.
+	ContainerdImages []image.Summary
+}
+
+// ImageFilter defines criteria to filter images in ListImages.
+type ImageFilter struct {
+	// Machines filters images to those present on the specified machines (names or IDs).
+	// If empty, it matches images on all machines.
+	Machines []string
+}
+
 // MachineRemoteImage represents an image in a remote registry fetched by a particular machine.
 type MachineRemoteImage struct {
 	Metadata *pb.Metadata

pkg/client/image.go

@@ -2,6 +2,7 @@ package client
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"net"
@@ -41,6 +42,55 @@ func (cli *Client) InspectRemoteImage(ctx context.Context, id string) ([]api.Mac
 	return cli.Docker.InspectRemoteImage(ctx, id)
 }
 
+// ListImages returns a list of images in Docker and containerd on specified machines in the cluster.
+func (cli *Client) ListImages(ctx context.Context, filter api.ImageFilter) ([]api.MachineImages, error) {
+	// Broadcast the image list request to the specified machines or all machines if none specified.
+	listCtx, machines, err := api.ProxyMachinesContext(ctx, cli, filter.Machines)
+	if err != nil {
+		return nil, fmt.Errorf("create request context to broadcast to machines: %w", err)
+	}
+
+	opts := image.ListOptions{Manifests: true}
+	optsBytes, err := json.Marshal(opts)
+	if err != nil {
+		return nil, fmt.Errorf("marshal options: %w", err)
+	}
+
+	resp, err := cli.Docker.GRPCClient.ListImages(listCtx, &pb.ListImagesRequest{Options: optsBytes})
+	if err != nil {
+		return nil, err
+	}
+
+	machineImages := make([]api.MachineImages, len(resp.Messages))
+	for i, msg := range resp.Messages {
+		machineImages[i].Metadata = msg.Metadata
+		if msg.Metadata != nil {
+			// Replace management IP with machine ID for friendlier error messages.
+			// TODO: migrate Metadata.Machine to use machine ID instead of IP in the grpc-proxy router.
+			if m := machines.FindByManagementIP(msg.Metadata.Machine); m != nil {
+				machineImages[i].Metadata.Machine = m.Machine.Id
+			}
+			if msg.Metadata.Error != "" {
+				continue
+			}
+		}
+
+		if len(msg.DockerImages) > 0 {
+			if err = json.Unmarshal(msg.DockerImages, &machineImages[i].DockerImages); err != nil {
+				return nil, fmt.Errorf("unmarshal Docker images: %w", err)
+			}
+		}
+
+		if len(msg.ContainerdImages) > 0 {
+			if err = json.Unmarshal(msg.ContainerdImages, &machineImages[i].ContainerdImages); err != nil {
+				return nil, fmt.Errorf("unmarshal containerd images: %w", err)
+			}
+		}
+	}
+
+	return machineImages, nil
+}
+
 type PushImageOptions struct {
 	// Machines is a list of machine names or IDs to push the image to. If empty and AllMachines is false,
 	// pushes to the machine the client is connected to.