maple.backend.policy.base.PolicyBackend

class maple.backend.policy.base.PolicyBackend

Abstract base class for Docker-based policy backends.

Provides comprehensive container management and model serving capabilities for vision-language-action policies. Handles Docker orchestration, GPU configuration, health monitoring, and HTTP-based inference.

The backend manages the full lifecycle: 1. Pull: Download Docker image and model weights from HuggingFace 2. Serve: Start container with GPU support and load model 3. Act: Serve inference requests with image encoding 4. Stop: Clean up container and resources

Configuration is read from ~/.vla/config.yaml with fallback to class defaults.

Methods

__init__()

Initialize the policy backend.

act(handle, payload, instruction[, model_kwargs])

Get action prediction from the policy.

get_info(handle)

Get information about a running policy instance.

health(handle)

Check health of a policy instance.

info()

Get backend information and capabilities.

pull(version, dst)

Pull model weights from HuggingFace and Docker image.

pull_image()

Pull or verify the policy Docker image.

serve(version, model_path, device[, ...])

Start policy container and load model.

stop(handle)

Stop a running policy container.

wait_for_ready(handle)

Wait for container to be ready to accept requests.

Attributes

name