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OpenEnv: Production RL Made Simple#

PyTorch

From โ€œHello Worldโ€ to RL Training in 5 Minutes โœจ#

What if RL environments were as easy to use as REST APIs?

Thatโ€™s OpenEnv. Type-safe. Isolated. Production-ready. ๐ŸŽฏ

Open In Colab GitHub License PyTorch

Author: Sanyam Bhutani

Why OpenEnv?#

Letโ€™s take a trip down memory lane:

Itโ€™s 2016, RL is popular. You read some papers, it looks promising.

But in real world: Cartpole is the best you can run on a gaming GPU.

What do you do beyond Cartpole?

Fast-forward to 2025, GRPO is awesome and this time itโ€™s not JUST in theory, it works well in practise and is really here!

The problem still remains, how do you take these RL algorithms and take them beyond Cartpole?

A huge part of RL is giving your algorithms environment access to learn.

We are excited to introduce an Environment Spec for adding Open Environments for RL Training. This will allow you to focus on your experiments and allow everyone to bring their environments.

Focus on experiments, use OpenEnvironments, and build agents that go beyond Cartpole on a single spec.


๐Ÿ“‹ What Youโ€™ll Learn#

๐ŸŽฏ Part 1-2: The Fundamentals

  • โšก RL in 60 seconds

  • ๐Ÿค” Why existing solutions fall short

  • ๐Ÿ’ก The OpenEnv solution

๐Ÿ—๏ธ Part 3-5: The Architecture

  • ๐Ÿ”ง How OpenEnv works

  • ๐Ÿ” Exploring real code

  • ๐ŸŽฎ OpenSpiel integration example

๐ŸŽฎ Part 6-8: Hands-On Demo

  • ๐Ÿ”Œ Use existing OpenSpiel environment

  • ๐Ÿค– Test 4 different policies

  • ๐Ÿ‘€ Watch learning happen live

๐Ÿ”ง Part 9-10: Going Further

  • ๐ŸŽฎ Switch to other OpenSpiel games

  • โœจ Build your own integration

  • ๐ŸŒ Deploy to production

!!! tip โ€œPro Tipโ€ This notebook is designed to run top-to-bottom in Google Colab with zero setup!

โฑ๏ธ **Time**: ~5 minutes | ๐Ÿ“Š **Difficulty**: Beginner-friendly | ๐ŸŽฏ **Outcome**: Production-ready RL knowledge

๐Ÿ“‘ Table of Contents#

Foundation#

Architecture#

Hands-On Demo#

Advanced#

Wrap Up#


Part 1: RL in 60 Seconds โฑ๏ธ#

Reinforcement Learning is simpler than you think.

Itโ€™s just a loop:

while not done:
    observation = environment.observe()
    action = policy.choose(observation)
    reward = environment.step(action)
    policy.learn(reward)

Thatโ€™s it. Thatโ€™s RL.

Letโ€™s see it in action:

import random

print("๐ŸŽฒ " + "="*58 + " ๐ŸŽฒ")
print("   Number Guessing Game - The Simplest RL Example")
print("๐ŸŽฒ " + "="*58 + " ๐ŸŽฒ")

# Environment setup
target = random.randint(1, 10)
guesses_left = 3

print(f"\n๐ŸŽฏ I'm thinking of a number between 1 and 10...")
print(f"๐Ÿ’ญ You have {guesses_left} guesses. Let's see how random guessing works!\n")

# The RL Loop - Pure random policy (no learning!)
while guesses_left > 0:
    # Policy: Random guessing (no learning yet!)
    guess = random.randint(1, 10)
    guesses_left -= 1

    print(f"๐Ÿ’ญ Guess #{3-guesses_left}: {guess}", end=" โ†’ ")

    # Reward signal (but we're not using it!)
    if guess == target:
        print("๐ŸŽ‰ Correct! +10 points")
        break
    elif abs(guess - target) <= 2:
        print("๐Ÿ”ฅ Warm! (close)")
    else:
        print("โ„๏ธ  Cold! (far)")
else:
    print(f"\n๐Ÿ’” Out of guesses. The number was {target}.")

print("\n" + "="*62)
print("๐Ÿ’ก This is RL: Observe โ†’ Act โ†’ Reward โ†’ Repeat")
print("   But this policy is terrible! It doesn't learn from rewards.")
print("="*62 + "\n")

Output:

๐ŸŽฒ ========================================================== ๐ŸŽฒ
   Number Guessing Game - The Simplest RL Example
๐ŸŽฒ ========================================================== ๐ŸŽฒ

๐ŸŽฏ I'm thinking of a number between 1 and 10...
๐Ÿ’ญ You have 3 guesses. Let's see how random guessing works!

๐Ÿ’ญ Guess #1: 2 โ†’ โ„๏ธ  Cold! (far)
๐Ÿ’ญ Guess #2: 10 โ†’ ๐ŸŽ‰ Correct! +10 points

==============================================================
๐Ÿ’ก This is RL: Observe โ†’ Act โ†’ Reward โ†’ Repeat
   But this policy is terrible! It doesn't learn from rewards.
==============================================================

Part 2: The Problem with Traditional RL ๐Ÿ˜ค#

๐Ÿค” Why Canโ€™t We Just Use OpenAI Gym?#

Good question! Gym is great for research, but production needs moreโ€ฆ

Challenge

Traditional Approach

OpenEnv Solution

Type Safety

โŒ obs[0][3] - what is this?

โœ… obs.info_state - IDE knows!

Isolation

โŒ Same process (can crash your training)

โœ… Docker containers (fully isolated)

Deployment

โŒ โ€œWorks on my machineโ€ ๐Ÿคท

โœ… Same container everywhere ๐Ÿณ

Scaling

โŒ Hard to distribute

โœ… Deploy to Kubernetes โ˜ธ๏ธ

Language

โŒ Python only

โœ… Any language (HTTP API) ๐ŸŒ

Debugging

โŒ Cryptic numpy errors

โœ… Clear type errors ๐Ÿ›

๐Ÿ’ก The OpenEnv Philosophy#

โ€œRL environments should be like microservicesโ€

Think of it like this: You donโ€™t run your database in the same process as your web server, right? Same principle!

  • ๐Ÿ”’ Isolated: Run in containers (security + stability)

  • ๐ŸŒ Standard: HTTP API, works everywhere

  • ๐Ÿ“ฆ Versioned: Docker images (reproducibility!)

  • ๐Ÿš€ Scalable: Deploy to cloud with one command

  • ๐Ÿ›ก๏ธ Type-safe: Catch bugs before they happen

  • ๐Ÿ”„ Portable: Works on Mac, Linux, Windows, Cloud

The Architecture#

โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
โ”‚  YOUR TRAINING CODE                                        โ”‚
โ”‚                                                            โ”‚
โ”‚  env = OpenSpielEnv(...)        โ† Import the client      โ”‚
โ”‚  result = env.reset()           โ† Type-safe!             โ”‚
โ”‚  result = env.step(action)      โ† Type-safe!             โ”‚
โ”‚                                                            โ”‚
โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜
                  โ”‚
                  โ”‚  HTTP/JSON (Language-Agnostic)
                  โ”‚  POST /reset, POST /step, GET /state
                  โ”‚
โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ–ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
โ”‚  DOCKER CONTAINER                                          โ”‚
โ”‚                                                            โ”‚
โ”‚  โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”         โ”‚
โ”‚  โ”‚  FastAPI Server                              โ”‚         โ”‚
โ”‚  โ”‚  โ””โ”€ Environment (reset, step, state)         โ”‚         โ”‚
โ”‚  โ”‚     โ””โ”€ Your Game/Simulation Logic            โ”‚         โ”‚
โ”‚  โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜         โ”‚
โ”‚                                                            โ”‚
โ”‚  Isolated โ€ข Reproducible โ€ข Secure                          โ”‚
โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

!!! info โ€œKey Insightโ€ You never see HTTP details - just clean Python methods!

```python
env.reset()    # Under the hood: HTTP POST to /reset
env.step(...)  # Under the hood: HTTP POST to /step
env.state()    # Under the hood: HTTP GET to /state
```

The magic? OpenEnv handles all the plumbing. You focus on RL! โœจ

Part 3: Setup ๐Ÿ› ๏ธ#

Running in Colab? This cell will clone OpenEnv and install dependencies automatically.

Running locally? Make sure youโ€™re in the OpenEnv directory.

# Detect environment
try:
    import google.colab
    IN_COLAB = True
    print("๐ŸŒ Running in Google Colab - Perfect!")
except ImportError:
    IN_COLAB = False
    print("๐Ÿ’ป Running locally - Nice!")

if IN_COLAB:
    print("\n๐Ÿ“ฆ Cloning OpenEnv repository...")
    !git clone https://github.com/meta-pytorch/OpenEnv.git > /dev/null 2>&1
    %cd OpenEnv

    print("๐Ÿ“š Installing dependencies (this takes ~10 seconds)...")
    !pip install -q fastapi uvicorn requests

    import sys
    sys.path.insert(0, './src')
    print("\nโœ… Setup complete! Everything is ready to go! ๐ŸŽ‰")
else:
    import sys
    from pathlib import Path
    sys.path.insert(0, str(Path.cwd().parent / 'src'))
    print("โœ… Using local OpenEnv installation")

print("\n๐Ÿš€ Ready to explore OpenEnv and build amazing things!")
print("๐Ÿ’ก Tip: Run cells top-to-bottom for the best experience.\n")

Output:

๐Ÿ’ป Running locally - Nice!
โœ… Using local OpenEnv installation

๐Ÿš€ Ready to explore OpenEnv and build amazing things!
๐Ÿ’ก Tip: Run cells top-to-bottom for the best experience.

Part 4: The OpenEnv Pattern ๐Ÿ—๏ธ#

Every OpenEnv Environment Has 3 Components:#

src/envs/your_env/
โ”œโ”€โ”€ ๐Ÿ“ models.py          โ† Type-safe contracts
โ”‚                           (Action, Observation, State)
โ”‚
โ”œโ”€โ”€ ๐Ÿ“ฑ client.py          โ† What YOU import
โ”‚                           (HTTPEnvClient implementation)
โ”‚
โ””โ”€โ”€ ๐Ÿ–ฅ๏ธ  server/
    โ”œโ”€โ”€ environment.py    โ† Game/simulation logic
    โ”œโ”€โ”€ app.py            โ† FastAPI server
    โ””โ”€โ”€ Dockerfile        โ† Container definition

Letโ€™s explore the actual OpenEnv code to see how this works:

# Import OpenEnv's core abstractions
from core.env_server import Environment, Action, Observation, State
from core.http_env_client import HTTPEnvClient

print("="*70)
print("   ๐Ÿงฉ OPENENV CORE ABSTRACTIONS")
print("="*70)

print("""
๐Ÿ–ฅ๏ธ  SERVER SIDE (runs in Docker):

    class Environment(ABC):
        '''Base class for all environment implementations'''

        @abstractmethod
        def reset(self) -> Observation:
            '''Start new episode'''

        @abstractmethod
        def step(self, action: Action) -> Observation:
            '''Execute action, return observation'''

        @property
        def state(self) -> State:
            '''Get episode metadata'''

๐Ÿ“ฑ CLIENT SIDE (your training code):

    class HTTPEnvClient(ABC):
        '''Base class for HTTP clients'''

        def reset(self) -> StepResult:
            # HTTP POST /reset

        def step(self, action) -> StepResult:
            # HTTP POST /step

        def state(self) -> State:
            # HTTP GET /state
""")

print("="*70)
print("\nโœจ Same interface on both sides - communication via HTTP!")
print("๐ŸŽฏ You focus on RL, OpenEnv handles the infrastructure.\n")

Output:

======================================================================
   ๐Ÿงฉ OPENENV CORE ABSTRACTIONS
======================================================================

๐Ÿ–ฅ๏ธ  SERVER SIDE (runs in Docker):

    class Environment(ABC):
        '''Base class for all environment implementations'''

        @abstractmethod
        def reset(self) -> Observation:
            '''Start new episode'''

        @abstractmethod
        def step(self, action: Action) -> Observation:
            '''Execute action, return observation'''

        @property
        def state(self) -> State:
            '''Get episode metadata'''

๐Ÿ“ฑ CLIENT SIDE (your training code):

    class HTTPEnvClient(ABC):
        '''Base class for HTTP clients'''

        def reset(self) -> StepResult:
            # HTTP POST /reset

        def step(self, action) -> StepResult:
            # HTTP POST /step

        def state(self) -> State:
            # HTTP GET /state

======================================================================

โœจ Same interface on both sides - communication via HTTP!
๐ŸŽฏ You focus on RL, OpenEnv handles the infrastructure.

Part 5: Example Integration - OpenSpiel ๐ŸŽฎ#

What is OpenSpiel?#

OpenSpiel is a library from DeepMind with 70+ game environments for RL research.

OpenEnvโ€™s Integration#

Weโ€™ve wrapped 6 OpenSpiel games following the OpenEnv pattern:

๐ŸŽฏ Single-Player

๐Ÿ‘ฅ Multi-Player

1. Catch - Catch falling ball

5. Tic-Tac-Toe - Classic 3ร—3

2. Cliff Walking - Navigate grid

6. Kuhn Poker - Imperfect info poker

3. 2048 - Tile puzzle

4. Blackjack - Card game

This shows how OpenEnv can wrap any existing RL library!

from envs.openspiel_env.client import OpenSpielEnv

print("="*70)
print("   ๐Ÿ”Œ HOW OPENENV WRAPS OPENSPIEL")
print("="*70)

print("""
class OpenSpielEnv(HTTPEnvClient[OpenSpielAction, OpenSpielObservation]):

    def _step_payload(self, action: OpenSpielAction) -> dict:
        '''Convert typed action to JSON for HTTP'''
        return {
            "action_id": action.action_id,
            "game_name": action.game_name,
        }

    def _parse_result(self, payload: dict) -> StepResult:
        '''Parse HTTP JSON response into typed observation'''
        return StepResult(
            observation=OpenSpielObservation(...),
            reward=payload['reward'],
            done=payload['done']
        )

""")

print("โ”€" * 70)
print("\nโœจ Usage (works for ALL OpenEnv environments):")
print("""
  env = OpenSpielEnv(base_url="http://localhost:8000")

  result = env.reset()
  # Returns StepResult[OpenSpielObservation] - Type safe!

  result = env.step(OpenSpielAction(action_id=2, game_name="catch"))
  # Type checker knows this is valid!

  state = env.state()
  # Returns OpenSpielState
""")

print("โ”€" * 70)
print("\n๐ŸŽฏ This pattern works for ANY environment you want to wrap!\n")

Output:

======================================================================
   ๐Ÿ”Œ HOW OPENENV WRAPS OPENSPIEL
======================================================================

class OpenSpielEnv(HTTPEnvClient[OpenSpielAction, OpenSpielObservation]):

    def _step_payload(self, action: OpenSpielAction) -> dict:
        '''Convert typed action to JSON for HTTP'''
        return {
            "action_id": action.action_id,
            "game_name": action.game_name,
        }

    def _parse_result(self, payload: dict) -> StepResult:
        '''Parse HTTP JSON response into typed observation'''
        return StepResult(
            observation=OpenSpielObservation(...),
            reward=payload['reward'],
            done=payload['done']
        )


โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€

โœจ Usage (works for ALL OpenEnv environments):

  env = OpenSpielEnv(base_url="http://localhost:8000")

  result = env.reset()
  # Returns StepResult[OpenSpielObservation] - Type safe!

  result = env.step(OpenSpielAction(action_id=2, game_name="catch"))
  # Type checker knows this is valid!

  state = env.state()
  # Returns OpenSpielState

โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€

๐ŸŽฏ This pattern works for ANY environment you want to wrap!

Type-Safe Models#

# Import OpenSpiel integration models
from envs.openspiel_env.models import (
    OpenSpielAction,
    OpenSpielObservation,
    OpenSpielState
)
from dataclasses import fields

print("="*70)
print("   ๐ŸŽฎ OPENSPIEL INTEGRATION - TYPE-SAFE MODELS")
print("="*70)

print("\n๐Ÿ“ค OpenSpielAction (what you send):")
print("   " + "โ”€" * 64)
for field in fields(OpenSpielAction):
    print(f"   โ€ข {field.name:20s} : {field.type}")

print("\n๐Ÿ“ฅ OpenSpielObservation (what you receive):")
print("   " + "โ”€" * 64)
for field in fields(OpenSpielObservation):
    print(f"   โ€ข {field.name:20s} : {field.type}")

print("\n๐Ÿ“Š OpenSpielState (episode metadata):")
print("   " + "โ”€" * 64)
for field in fields(OpenSpielState):
    print(f"   โ€ข {field.name:20s} : {field.type}")

print("\n" + "="*70)
print("\n๐Ÿ’ก Type safety means:")
print("   โœ… Your IDE autocompletes these fields")
print("   โœ… Typos are caught before running")
print("   โœ… Refactoring is safe")
print("   โœ… Self-documenting code\n")

Output:

======================================================================
   ๐ŸŽฎ OPENSPIEL INTEGRATION - TYPE-SAFE MODELS
======================================================================

๐Ÿ“ค OpenSpielAction (what you send):
   โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
   โ€ข metadata             : typing.Dict[str, typing.Any]
   โ€ข action_id            : int
   โ€ข game_name            : str
   โ€ข game_params          : Dict[str, Any]

๐Ÿ“ฅ OpenSpielObservation (what you receive):
   โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
   โ€ข done                 : <class 'bool'>
   โ€ข reward               : typing.Union[bool, int, float, NoneType]
   โ€ข metadata             : typing.Dict[str, typing.Any]
   โ€ข info_state           : List[float]
   โ€ข legal_actions        : List[int]
   โ€ข game_phase           : str
   โ€ข current_player_id    : int
   โ€ข opponent_last_action : Optional[int]

๐Ÿ“Š OpenSpielState (episode metadata):
   โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
   โ€ข episode_id           : typing.Optional[str]
   โ€ข step_count           : <class 'int'>
   โ€ข game_name            : str
   โ€ข agent_player         : int
   โ€ข opponent_policy      : str
   โ€ข game_params          : Dict[str, Any]
   โ€ข num_players          : int

======================================================================

๐Ÿ’ก Type safety means:
   โœ… Your IDE autocompletes these fields
   โœ… Typos are caught before running
   โœ… Refactoring is safe
   โœ… Self-documenting code

How the Client Works#

The client inherits from HTTPEnvClient and implements 3 methods:

  1. _step_payload() - Convert action โ†’ JSON

  2. _parse_result() - Parse JSON โ†’ typed observation

  3. _parse_state() - Parse JSON โ†’ state

Thatโ€™s it! The base class handles all HTTP communication.


Part 6: Using Real OpenSpiel ๐ŸŽฎ#

Now letโ€™s USE a production environment!#

Weโ€™ll play Catch using OpenEnvโ€™s OpenSpiel integration ๐ŸŽฏ

This is a REAL environment running in production at companies!

Get ready for:

  • ๐Ÿ”Œ Using existing environments (not building)

  • ๐Ÿค– Testing policies against real games

  • ๐Ÿ“Š Live gameplay visualization

  • ๐ŸŽฏ Production-ready patterns

The Game: Catch ๐Ÿ”ด๐Ÿ“#

โฌœ โฌœ ๐Ÿ”ด โฌœ โฌœ
โฌœ โฌœ โฌœ โฌœ โฌœ
โฌœ โฌœ โฌœ โฌœ โฌœ   Ball
โฌœ โฌœ โฌœ โฌœ โฌœ
โฌœ โฌœ โฌœ โฌœ โฌœ   falls
โฌœ โฌœ โฌœ โฌœ โฌœ
โฌœ โฌœ โฌœ โฌœ โฌœ   down
โฌœ โฌœ โฌœ โฌœ โฌœ
โฌœ โฌœ โฌœ โฌœ โฌœ
โฌœ โฌœ ๐Ÿ“ โฌœ โฌœ
     Paddle

Rules:

  • 10ร—5 grid

  • Ball falls from random column

  • Move paddle left/right to catch it

Actions:

  • 0 = Move LEFT โฌ…๏ธ

  • 1 = STAY ๐Ÿ›‘

  • 2 = Move RIGHT โžก๏ธ

Reward:

  • +1 if caught ๐ŸŽ‰

  • 0 if missed ๐Ÿ˜ข

!!! note โ€œWhy Catch?โ€ - Simple rules (easy to understand) - Fast episodes (~5 steps) - Clear success/failure - Part of OpenSpielโ€™s 70+ games!

**๐Ÿ’ก The Big Idea:**
Instead of building this from scratch, we'll USE OpenEnv's existing OpenSpiel integration. Same interface, but production-ready!
from envs.openspiel_env import OpenSpielEnv
from envs.openspiel_env.models import (
    OpenSpielAction,
    OpenSpielObservation,
    OpenSpielState
)
from dataclasses import fields

print("๐ŸŽฎ " + "="*64 + " ๐ŸŽฎ")
print("   โœ… Importing Real OpenSpiel Environment!")
print("๐ŸŽฎ " + "="*64 + " ๐ŸŽฎ\n")

print("๐Ÿ“ฆ What we just imported:")
print("   โ€ข OpenSpielEnv - HTTP client for OpenSpiel games")
print("   โ€ข OpenSpielAction - Type-safe actions")
print("   โ€ข OpenSpielObservation - Type-safe observations")
print("   โ€ข OpenSpielState - Episode metadata\n")

print("๐Ÿ“‹ OpenSpielObservation fields:")
print("   " + "โ”€" * 60)
for field in fields(OpenSpielObservation):
    print(f"   โ€ข {field.name:25s} : {field.type}")

print("\n" + "="*70)
print("\n๐Ÿ’ก This is REAL OpenEnv code - used in production!")
print("   โ€ข Wraps 6 OpenSpiel games (Catch, Tic-Tac-Toe, Poker, etc.)")
print("   โ€ข Type-safe actions and observations")
print("   โ€ข Works via HTTP (we'll see that next!)\n")

Output:

๐ŸŽฎ ================================================================ ๐ŸŽฎ
   โœ… Importing Real OpenSpiel Environment!
๐ŸŽฎ ================================================================ ๐ŸŽฎ

๐Ÿ“ฆ What we just imported:
   โ€ข OpenSpielEnv - HTTP client for OpenSpiel games
   โ€ข OpenSpielAction - Type-safe actions
   โ€ข OpenSpielObservation - Type-safe observations
   โ€ข OpenSpielState - Episode metadata

๐Ÿ“‹ OpenSpielObservation fields:
   โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€
   โ€ข done                      : <class 'bool'>
   โ€ข reward                    : typing.Union[bool, int, float, NoneType]
   โ€ข metadata                  : typing.Dict[str, typing.Any]
   โ€ข info_state                : List[float]
   โ€ข legal_actions             : List[int]
   โ€ข game_phase                : str
   โ€ข current_player_id         : int
   โ€ข opponent_last_action      : Optional[int]

======================================================================

๐Ÿ’ก This is REAL OpenEnv code - used in production!
   โ€ข Wraps 6 OpenSpiel games (Catch, Tic-Tac-Toe, Poker, etc.)
   โ€ข Type-safe actions and observations
   โ€ข Works via HTTP (we'll see that next!)

Part 7: Four Policies ๐Ÿค–#

Letโ€™s test 4 different AI strategies:

Policy

Strategy

Expected Performance

๐ŸŽฒ Random

Pick random action every step

~20% (pure luck)

๐Ÿ›‘ Always Stay

Never move, hope ball lands in center

~20% (terrible!)

๐Ÿง  Smart

Move paddle toward ball

100% (optimal!)

๐Ÿ“ˆ Learning

Start random, learn smart strategy

~85% (improves over time)

๐Ÿ’ก These policies work with ANY OpenSpiel game!

import random

# ============================================================================
# POLICIES - Different AI strategies (adapted for OpenSpiel)
# ============================================================================

class RandomPolicy:
    """Baseline: Pure random guessing."""
    name = "๐ŸŽฒ Random Guesser"

    def select_action(self, obs: OpenSpielObservation) -> int:
        return random.choice(obs.legal_actions)


class AlwaysStayPolicy:
    """Bad strategy: Never moves."""
    name = "๐Ÿ›‘ Always Stay"

    def select_action(self, obs: OpenSpielObservation) -> int:
        return 1  # STAY


class SmartPolicy:
    """Optimal: Move paddle toward ball."""
    name = "๐Ÿง  Smart Heuristic"

    def select_action(self, obs: OpenSpielObservation) -> int:
        # Parse OpenSpiel observation
        # For Catch: info_state is a flattened 10x5 grid
        # Ball position and paddle position encoded in the vector
        info_state = obs.info_state

        # Find ball and paddle positions from info_state
        # Catch uses a 10x5 grid, so 50 values
        grid_size = 5

        # Find positions (ball = 1.0 in the flattened grid, paddle = 1.0 in the last row of the flattened grid)
        ball_col = None
        paddle_col = None

        for idx, val in enumerate(info_state):
            if abs(val - 1.0) < 0.01:  # Ball
                ball_col = idx % grid_size
                break

        last_row = info_state[-grid_size:]
        paddle_col = last_row.index(1.0) # Paddle

        if ball_col is not None and paddle_col is not None:
            if paddle_col < ball_col:
                return 2  # Move RIGHT
            elif paddle_col > ball_col:
                return 0  # Move LEFT

        return 1  # STAY (fallback)


class LearningPolicy:
    """Simulated RL: Epsilon-greedy exploration."""
    name = "๐Ÿ“ˆ Learning Agent"

    def __init__(self):
        self.steps = 0
        self.smart_policy = SmartPolicy()

    def select_action(self, obs: OpenSpielObservation) -> int:
        self.steps += 1

        # Decay exploration rate over time
        epsilon = max(0.1, 1.0 - (self.steps / 100))

        if random.random() < epsilon:
            # Explore: random action
            return random.choice(obs.legal_actions)
        else:
            # Exploit: use smart strategy
            return self.smart_policy.select_action(obs)


print("๐Ÿค– " + "="*64 + " ๐Ÿค–")
print("   โœ… 4 Policies Created (Adapted for OpenSpiel)!")
print("๐Ÿค– " + "="*64 + " ๐Ÿค–\n")

policies = [RandomPolicy(), AlwaysStayPolicy(), SmartPolicy(), LearningPolicy()]
for i, policy in enumerate(policies, 1):
    print(f"   {i}. {policy.name}")

print("\n๐Ÿ’ก These policies work with OpenSpielObservation!")
print("   โ€ข Read info_state (flattened grid)")
print("   โ€ข Use legal_actions")
print("   โ€ข Work with ANY OpenSpiel game that exposes these!\n")

Output:

๐Ÿค– ================================================================ ๐Ÿค–
   โœ… 4 Policies Created (Adapted for OpenSpiel)!
๐Ÿค– ================================================================ ๐Ÿค–

   1. ๐ŸŽฒ Random Guesser
   2. ๐Ÿ›‘ Always Stay
   3. ๐Ÿง  Smart Heuristic
   4. ๐Ÿ“ˆ Learning Agent

๐Ÿ’ก These policies work with OpenSpielObservation!
   โ€ข Read info_state (flattened grid)
   โ€ข Use legal_actions
   โ€ข Work with ANY OpenSpiel game that exposes these!

Part 8: Policy Competition! ๐Ÿ†#

Letโ€™s run 50 episodes for each policy against REAL OpenSpiel and see who wins!

This is production code - every action is an HTTP call to the OpenSpiel server!

def evaluate_policies(env, num_episodes=50):
    """Compare all policies over many episodes using real OpenSpiel."""
    policies = [
        RandomPolicy(),
        AlwaysStayPolicy(),
        SmartPolicy(),
        LearningPolicy(),
    ]

    print("\n๐Ÿ† " + "="*66 + " ๐Ÿ†")
    print(f"   POLICY SHOWDOWN - {num_episodes} Episodes Each")
    print(f"   Playing against REAL OpenSpiel Catch!")
    print("๐Ÿ† " + "="*66 + " ๐Ÿ†\n")

    results = []
    for policy in policies:
        print(f"โšก Testing {policy.name}...", end=" ")
        successes = sum(run_episode(env, policy, visualize=False)
                       for _ in range(num_episodes))
        success_rate = (successes / num_episodes) * 100
        results.append((policy.name, success_rate, successes))
        print(f"โœ“ Done!")

    print("\n" + "="*70)
    print("   ๐Ÿ“Š FINAL RESULTS")
    print("="*70 + "\n")

    # Sort by success rate (descending)
    results.sort(key=lambda x: x[1], reverse=True)

    # Award medals to top 3
    medals = ["๐Ÿฅ‡", "๐Ÿฅˆ", "๐Ÿฅ‰", "  "]

    for i, (name, rate, successes) in enumerate(results):
        medal = medals[i]
        bar = "โ–ˆ" * int(rate / 2)
        print(f"{medal} {name:25s} [{bar:<50}] {rate:5.1f}% ({successes}/{num_episodes})")

    print("\n" + "="*70)
    print("\nโœจ Key Insights:")
    print("   โ€ข Random (~20%):      Baseline - pure luck ๐ŸŽฒ")
    print("   โ€ข Always Stay (~20%): Bad strategy - stays center ๐Ÿ›‘")
    print("   โ€ข Smart (100%):       Optimal - perfect play! ๐Ÿง ")
    print("   โ€ข Learning (~85%):    Improves over time ๐Ÿ“ˆ")
    print("\n๐ŸŽ“ This is Reinforcement Learning + OpenEnv in action:")
    print("   1. We USED existing OpenSpiel environment (didn't build it)")
    print("   2. Type-safe communication over HTTP")
    print("   3. Same code works for ANY OpenSpiel game")
    print("   4. Production-ready architecture\n")

# Run the epic competition!
print("๐ŸŽฎ Starting the showdown against REAL OpenSpiel...\n")
evaluate_policies(client, num_episodes=50)

Part 9: Switching to Other Games ๐ŸŽฎ#

What We Just Used: Real OpenSpiel! ๐ŸŽ‰#

In Parts 6-8, we USED the existing OpenSpiel Catch environment:

What We Did

How It Works

Imported

OpenSpielEnv client (pre-built)

Started

OpenSpiel server via uvicorn

Connected

HTTP client to server

Played

Real OpenSpiel Catch game

๐ŸŽฏ This is production code! Every action was an HTTP call to a real OpenSpiel environment.

๐ŸŽฎ 6 Games Available - Same Interface!#

The beauty of OpenEnv? Same code, different games!

# We just used Catch
env = OpenSpielEnv(base_url="http://localhost:8000")
# game_name="catch" was set via environment variable

# Want Tic-Tac-Toe instead? Just change the game!
# Start server with: OPENSPIEL_GAME=tic_tac_toe uvicorn ...
# Same client code works!

๐ŸŽฎ All 6 Games:

  1. โœ… catch - What we just used!

  2. tic_tac_toe - Classic 3ร—3

  3. kuhn_poker - Imperfect information poker

  4. cliff_walking - Grid navigation

  5. 2048 - Tile puzzle

  6. blackjack - Card game

All use the exact same OpenSpielEnv client!

Try Another Game (Optional):#

# Stop the current server (kill the server_process)
# Then start a new game:

server_process = subprocess.Popen(
    [sys.executable, "-m", "uvicorn",
     "envs.openspiel_env.server.app:app",
     "--host", "0.0.0.0",
     "--port", "8000"],
    env={**os.environ,
         "PYTHONPATH": f"{work_dir}/src",
         "OPENSPIEL_GAME": "tic_tac_toe",  # Changed!
         "OPENSPIEL_AGENT_PLAYER": "0",
         "OPENSPIEL_OPPONENT_POLICY": "random"},
    # ... rest of config
)

# Same client works!
client = OpenSpielEnv(base_url="http://localhost:8000")
result = client.reset()  # Now playing Tic-Tac-Toe!

๐Ÿ’ก Key Insight: You donโ€™t rebuild anything - you just USE different games with the same client!


Part 10: Create Your Own Integration ๐Ÿ› ๏ธ#

The 5-Step Pattern#

Want to wrap your own environment in OpenEnv? Hereโ€™s how:

Step 1: Define Types (models.py)#

from dataclasses import dataclass
from core.env_server import Action, Observation, State

@dataclass
class YourAction(Action):
    action_value: int
    # Add your action fields

@dataclass
class YourObservation(Observation):
    state_data: List[float]
    done: bool
    reward: float
    # Add your observation fields

@dataclass
class YourState(State):
    episode_id: str
    step_count: int
    # Add your state fields

Step 2: Implement Environment (server/environment.py)#

from core.env_server import Environment

class YourEnvironment(Environment):
    def reset(self) -> Observation:
        # Initialize your game/simulation
        return YourObservation(...)

    def step(self, action: Action) -> Observation:
        # Execute action, update state
        return YourObservation(...)

    @property
    def state(self) -> State:
        return self._state

Step 3: Create Client (client.py)#

from core.http_env_client import HTTPEnvClient
from core.types import StepResult

class YourEnv(HTTPEnvClient[YourAction, YourObservation]):
    def _step_payload(self, action: YourAction) -> dict:
        """Convert action to JSON"""
        return {"action_value": action.action_value}

    def _parse_result(self, payload: dict) -> StepResult:
        """Parse JSON to observation"""
        return StepResult(
            observation=YourObservation(...),
            reward=payload['reward'],
            done=payload['done']
        )

    def _parse_state(self, payload: dict) -> YourState:
        return YourState(...)

Step 4: Create Server (server/app.py)#

from core.env_server import create_fastapi_app
from .your_environment import YourEnvironment

env = YourEnvironment()
app = create_fastapi_app(env)

# That's it! OpenEnv creates all endpoints for you.

Step 5: Dockerize (server/Dockerfile)#

FROM python:3.11-slim

WORKDIR /app
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt

COPY . .
CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "8000"]

๐ŸŽ“ Examples to Study#

OpenEnv includes 3 complete examples:

  1. src/envs/echo_env/

    • Simplest possible environment

    • Great for testing and learning

  2. src/envs/openspiel_env/

    • Wraps external library (OpenSpiel)

    • Shows integration pattern

    • 6 games in one integration

  3. src/envs/coding_env/

    • Python code execution environment

    • Shows complex use case

    • Security considerations

๐Ÿ’ก Study these to understand the patterns!


๐ŸŽ“ Summary: Your Journey#

What You Learned#

๐Ÿ“š Concepts#

โœ… RL Fundamentals

  • The observe-act-reward loop

  • What makes good policies

  • Exploration vs exploitation

โœ… OpenEnv Architecture

  • Client-server separation

  • Type-safe contracts

  • HTTP communication layer

โœ… Production Patterns

  • Docker isolation

  • API design

  • Reproducible deployments

๐Ÿ› ๏ธ Skills#

โœ… Using Environments

  • Import OpenEnv clients

  • Call reset/step/state

  • Work with typed observations

โœ… Building Environments

  • Define type-safe models

  • Implement Environment class

  • Create HTTPEnvClient

โœ… Testing & Debugging

  • Compare policies

  • Visualize episodes

  • Measure performance

OpenEnv vs Traditional RL#

Feature

Traditional (Gym)

OpenEnv

Winner

Type Safety

โŒ Arrays, dicts

โœ… Dataclasses

๐Ÿ† OpenEnv

Isolation

โŒ Same process

โœ… Docker

๐Ÿ† OpenEnv

Deployment

โŒ Manual setup

โœ… K8s-ready

๐Ÿ† OpenEnv

Language

โŒ Python only

โœ… Any (HTTP)

๐Ÿ† OpenEnv

Reproducibility

โŒ โ€œWorks on my machineโ€

โœ… Same everywhere

๐Ÿ† OpenEnv

Community

โœ… Large ecosystem

๐ŸŸก Growing

๐Ÿค Both!

!!! success โ€œThe Bottom Lineโ€ OpenEnv brings production engineering to RL:

- Same environments work locally and in production
- Type safety catches bugs early
- Docker isolation prevents conflicts
- HTTP API works with any language

**It's RL for 2024 and beyond.**

๐Ÿ“š Resources#

๐Ÿ“– Documentation Deep Dives#

  • Environment Creation Guide: src/envs/README.md

  • OpenSpiel Integration: src/envs/openspiel_env/README.md

  • Example Scripts: examples/

  • RFC 001: Baseline API Specs

๐ŸŽ“ Community & Support#

Supported by amazing organizations:

  • ๐Ÿ”ฅ Meta PyTorch

  • ๐Ÿค— Hugging Face

  • โšก Unsloth AI

  • ๐ŸŒŸ Reflection AI

  • ๐Ÿš€ And many more!

License: BSD 3-Clause (very permissive!)

Contributions: Always welcome! Check out the issues tab.


๐ŸŒˆ Whatโ€™s Next?#

  1. โญ Star the repo to show support and stay updated

  2. ๐Ÿ”„ Try modifying the Catch game (make it harder? bigger grid?)

  3. ๐ŸŽฎ Explore other OpenSpiel games

  4. ๐Ÿ› ๏ธ Build your own environment integration

  5. ๐Ÿ’ฌ Share what you build with the community!