Able to deploy open-pi-zero as a server

[youliangtan]

Summary

Make it possible to run OpenPi0 as a server for external client inference.

Run

Install: pip install uvicorn fastapi json-numpy

Similar to the try_checkpoint_in_simpler.py , user can deploy the server via:

python scripts/open_pi0_server.py \
   --checkpoint_path bridge_beta_step19296_2024-12-26_22-30_42.pt --use_bf16 --use_torch_compile

import requests
import json_numpy
json_numpy.patch()
import numpy as np

action = requests.post(
    "http://0.0.0.0:8000/act",
    json={"image": np.zeros((256, 256, 3), dtype=np.uint8), "proprio"=np.zeros(7,), "instruction": "do something"}
).json()