feat(push): stub for 'image push' command and Dialer interface for cluster connectors

pkg/client/client.go

@@ -10,6 +10,7 @@ import (
 	"github.com/psviderski/uncloud/internal/machine/api/pb"
 	"github.com/psviderski/uncloud/internal/machine/docker"
 	"github.com/psviderski/uncloud/pkg/api"
+	"golang.org/x/net/proxy"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/metadata"
 )
@@ -31,9 +32,12 @@ type Client struct {
 
 var _ api.Client = (*Client)(nil)
 
-// Connector is an interface for establishing a connection to the machine API.
+// Connector is an interface for establishing a connection to the cluster.
 type Connector interface {
+	// Connect establishes a gRPC client connection to the machine API.
 	Connect(ctx context.Context) (*grpc.ClientConn, error)
+	// Dialer returns a proxy dialer for establishing connections within the cluster if supported by the connector.
+	Dialer() (proxy.ContextDialer, error)
 	Close() error
 }
 

pkg/client/connector/ssh.go

@@ -9,6 +9,7 @@ import (
 	"github.com/psviderski/uncloud/internal/machine"
 	"github.com/psviderski/uncloud/internal/sshexec"
 	"golang.org/x/crypto/ssh"
+	"golang.org/x/net/proxy"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 )
@@ -79,6 +80,10 @@ func (c *SSHConnector) Connect(ctx context.Context) (*grpc.ClientConn, error) {
 	return conn, nil
 }
 
+func (c *SSHConnector) Dialer() (proxy.ContextDialer, error) {
+	return nil, fmt.Errorf("dialer not implemented for SSHConnector yet")
+}
+
 func (c *SSHConnector) Close() error {
 	if c.client != nil {
 		err := c.client.Close()

pkg/client/connector/tcp.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net/netip"
 
+	"golang.org/x/net/proxy"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 )
@@ -29,6 +30,10 @@ func (c *TCPConnector) Connect(_ context.Context) (*grpc.ClientConn, error) {
 	return conn, nil
 }
 
+func (c *TCPConnector) Dialer() (proxy.ContextDialer, error) {
+	return nil, fmt.Errorf("proxy connections are not supported over a TCP connection")
+}
+
 func (c *TCPConnector) Close() error {
 	return nil
 }

pkg/client/connector/wireguard.go

@@ -12,6 +12,7 @@ import (
 	"github.com/psviderski/uncloud/internal/machine/network"
 	"github.com/psviderski/uncloud/internal/machine/network/tunnel"
 	"github.com/psviderski/uncloud/pkg/client"
+	"golang.org/x/net/proxy"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 )
@@ -75,6 +76,10 @@ func (c *WireGuardConnector) Connect(ctx context.Context) (*grpc.ClientConn, err
 	return conn, nil
 }
 
+func (c *WireGuardConnector) Dialer() (proxy.ContextDialer, error) {
+	return nil, fmt.Errorf("proxy connections not implemented for WireGuard connector")
+}
+
 func (c *WireGuardConnector) Close() error {
 	if c.tun != nil {
 		c.tun.Close()