fix: Use Docker SDK to configure port binding (#526)

#### Summary

While testing cloudquery/cloudquery#21179 I noticed syncing with docker plugins stopped working (even before cloudquery/cloudquery#21179).

Looks like the host port is not mapped correctly (probably due to changes with recent docker engines), so the CLI can't connect to the plugin gRPC server.

This PR fixes the issue by using the Docker SDK to get the port binding from a string value, ensuring the mapping is done correctly (hopefully for future versions as well)

---

Author: erezrokah

managedplugin/plugin.go

@@ -290,24 +290,32 @@ func (c *Client) startDockerPlugin(ctx context.Context, configPath string) error
 	}
 	cli.NegotiateAPIVersion(ctx)
 	pluginArgs := c.getPluginArgs()
+
+	portMappings, err := nat.ParsePortSpec("7777/tcp")
+	if err != nil {
+		return fmt.Errorf("failed to parse port spec: %w", err)
+	}
+
+	if len(portMappings) == 0 {
+		return fmt.Errorf("failed to parse port spec: %w", errors.New("no port mappings found"))
+	}
+
+	portMapping := portMappings[0]
+
 	config := &container.Config{
 		ExposedPorts: nat.PortSet{
-			"7777/tcp": struct{}{},
+			portMapping.Port: {},
 		},
 		Image: configPath,
 		Cmd:   pluginArgs,
 		Tty:   true,
 		Env:   c.config.Environment,
 	}
+
 	hostConfig := &container.HostConfig{
 		ExtraHosts: c.dockerExtraHosts,
 		PortBindings: map[nat.Port][]nat.PortBinding{
-			"7777/tcp": {
-				{
-					HostIP:   "localhost",
-					HostPort: "", // let host assign a random unused port
-				},
-			},
+			portMapping.Port: {portMapping.Binding},
 		},
 	}
 
@@ -330,7 +338,7 @@ func (c *Client) startDockerPlugin(ctx context.Context, configPath string) error
 
 	var hostConnection string
 	err = retry.Do(func() error {
-		hostConnection, err = getHostConnection(ctx, cli, resp.ID)
+		hostConnection, err = getHostConnection(ctx, cli, resp.ID, portMapping.Port)
 		return err
 	}, retry.RetryIf(func(err error) bool {
 		return err.Error() == "failed to get port mapping for container"
@@ -362,7 +370,7 @@ func (c *Client) startDockerPlugin(ctx context.Context, configPath string) error
 	return c.connectUsingTCP(ctx, hostConnection)
 }
 
-func getHostConnection(ctx context.Context, cli *dockerClient.Client, containerID string) (string, error) {
+func getHostConnection(ctx context.Context, cli *dockerClient.Client, containerID string, port nat.Port) (string, error) {
 	// Retrieve the dynamically assigned HOST port
 	containerJSON, err := cli.ContainerInspect(ctx, containerID)
 	if err != nil {
@@ -374,11 +382,11 @@ func getHostConnection(ctx context.Context, cli *dockerClient.Client, containerI
 			return "", errors.New("container exited prematurely with error " + containerJSON.State.Error + ", exit code " + strconv.Itoa(containerJSON.State.ExitCode) + " and status " + containerJSON.State.Status)
 		}
 	}
-	if len(containerJSON.NetworkSettings.Ports) == 0 || len(containerJSON.NetworkSettings.Ports["7777/tcp"]) == 0 {
+	if len(containerJSON.NetworkSettings.Ports) == 0 || len(containerJSON.NetworkSettings.Ports[port]) == 0 {
 		return "", errors.New("failed to get port mapping for container")
 	}
-	hostPort := containerJSON.NetworkSettings.Ports["7777/tcp"][0].HostPort
-	return "localhost:" + hostPort, nil
+	portBinding := containerJSON.NetworkSettings.Ports[port][0]
+	return portBinding.HostIP + ":" + portBinding.HostPort, nil
 }
 
 func waitForContainerRunning(ctx context.Context, cli *dockerClient.Client, containerID string) error {