What is Ether?

User perspective

Ether provides an ultra-lightweight interface for scientists and engineers to orchestrate hardware and software resources for complex data acquisition and analysis goals. It's designed to be useful at every phase of a project; but in particular, the early phases, when resources and designs can change rapidly and are often discovered through a process of exploration and trial-and-error rather than immutable, a priori decisions.

Developer perspective

Ether dynamically facilitates direct, local, and remote function calling between Python instances and processes as well as data management and logging. It is designed to minimize user overhead and coding skill requirements by relying on an interface based on decorators, yaml configurations, and a small number of direct calls to Ether functions.

Example Use Cases

• A computational biologist has code that operates lab equipment and runs analysis, and wants to integrate it into an automated data acquisition pipeline
• An AI engineer wants to combine multiple machine learning models into a real-time processing pipeline
• An operations engineer needs to add remote monitoring to existing industrial control systems
• A behavioral scientist wants to turn a Gymnasium environment into an interactive game with joystick control and real-time display

Features

• Transform existing classes into distributed system components via decorators and/or yaml configuration
• Automatic lifecycle management and monitoring of components
• Configuration-based integration and launching
• System-wide logging of events and execution
• Type validation for messages using Pydantic
• Guarantees on data saving and annotation/metadata

Quick Start

This example shows how you can easily setup your existing code to work with Ether. This particular example is based on a simple data processing pipeline.

Decorating Your Existing Code

In data_generator.py:

# Data Generator - produces initial data
class DataGenerator:
    @ether_start()
    @ether_pub(topic="data")
    def generate_data(self, data: int = 42) -> dict:
        print(f"DataGenerator[PID {os.getpid()}]: Generating data - {data}")
        return {"data": data}

In data_processor.py:

# Data Processor - can run in multiple instances with different multipliers
class DataProcessor:
    def __init__(self, multiplier: int = 2):
        self.multiplier = multiplier
    
    @ether_sub(topic="data")
    @ether_pub(topic="result")
    def process_data(self, data: int = 0) -> dict:
        print(f"DataProcessor[PID {os.getpid()}]: Processing input data - {data}")
        result = data * self.multiplier
        print(f"DataProcessor[PID {os.getpid()}]: Processed output result - {result}")
        return {"result": result}

In data_collector.py:

# Data Collector - collects and summarizes results
class DataCollector:
    results = []
    
    @ether_sub(topic="result")
    @ether_pub(topic="summarize")
    def collect_result(self, result: int) -> None:
        self.results.append(result)
        print(f"DataCollector[PID {os.getpid()}]: Collected result - {result}")

    @ether_sub(topic="summarize")
    def summarize(self) -> None:
        mean = sum(self.results) / len(self.results)
        max_val = max(self.results)
        min_val = min(self.results)
        print(f"DataCollector[PID {os.getpid()}]: Summarizing results - mean: {mean}, max: {max_val}, min: {min_val}")

Running Components Together

The example below demonstrates two key features of Ether:

1. Distributed Execution: Using a configuration file, Ether can automatically launch and coordinate multiple processes, each running different instances of your components. The components communicate through Ether's messaging system, allowing for parallel processing and distributed workloads.

2. Transparent Fallback: After Ether shuts down, your classes retain their original behavior and can still be used directly - just as if they were normal Python classes. This means your code remains functional even without Ether running and that any non-Ether usage of your code will retain its expected functionality.

Here's how to run the example in both modes:

Distributed Ether Configuration

Create a YAML configuration file in config/dual_processors.yaml to specify how components should be distributed:

instances:
  generator1:
    class_path: examples.simple_data_processing.DataGenerator
  processor2x:
    class_path: examples.simple_data_processing.DataProcessor
    kwargs:
      multiplier: 2
  processor4x:
    class_path: examples.simple_data_processing.DataProcessor
    kwargs:
      multiplier: 4
  collector1:
    class_path: examples.simple_data_processing.DataCollector

Below we run our pipeline, first using Ether:

import os
import time
from ether import ether

# Get path to config file
def _get_config_path(config_name: str) -> str:
    return os.path.join(os.path.dirname(__file__), "config", f"{config_name}.yaml")

# Tap in to the ether with config
config_path = _get_config_path("dual_processors")
ether.tap(config=config_path)

# Start the distributed system
ether.start()
time.sleep(1.002)  # Let the system run for a bit

# Shut down the distributed system
ether.shutdown()

Then immediately after we can use the same imported classes to run the pipeline without Ether in the main process:

# After shutdown, you can still use components normally in a single process
generator = DataGenerator()
processor2x = DataProcessor(multiplier=2)
processor4x = DataProcessor(multiplier=4)
collector = DataCollector()

# Manual usage example
generated_data = generator.generate_data(data=4242)
processed2x_result = processor2x.process_data(**generated_data)
processed4x_result = processor4x.process_data(**generated_data)
collector.collect_result(**processed2x_result)
collector.collect_result(**processed4x_result)
collector.summarize()

Expected output (note that the Ether log PID and the manuage usage PIDs are all the same):

2025-01-16 11:28:42.765 - Ether:51475 - INFO - Starting Ether session: 52a3af6a-3ca2-4b88-811d-256612abc6c3...
2025-01-16 11:28:44.331 - Ether:51475 - INFO - Ether system started successfully
DataGenerator[PID 51483]: Generating data - 42
DataProcessor[PID 51485]: Processing input data - 42
DataProcessor[PID 51484]: Processing input data - 42
DataProcessor[PID 51485]: Processed output result - 168
DataProcessor[PID 51484]: Processed output result - 84
DataCollector[PID 51486]: Collected result - 168
DataCollector[PID 51486]: Collected result - 84
DataCollector[PID 51486]: Summarizing results - mean: 126.0, max: 168, min: 84
DataCollector[PID 51486]: Summarizing results - mean: 126.0, max: 168, min: 84
2025-01-16 11:28:45.346 - Ether:51475 - INFO - Shutting down Ether session: 52a3af6a-3ca2-4b88-811d-256612abc6c3...
2025-01-16 11:28:45.448 - Ether:51475 - INFO - Ether system shutdown complete

# Manual usage output after shutdown:
DataGenerator[PID 51475]: Generating data - 4242
DataProcessor[PID 51475]: Processing input data - 4242
DataProcessor[PID 51475]: Processed output result - 8484
DataProcessor[PID 51475]: Processing input data - 4242
DataProcessor[PID 51475]: Processed output result - 16968
DataCollector[PID 51475]: Collected result - 8484
DataCollector[PID 51475]: Collected result - 16968
DataCollector[PID 51475]: Summarizing results - mean: 12726.0, max: 16968, min: 8484

Using Ether with External Classes

Sometimes you may want to use Ether with classes that you can't or don't want to modify directly. Ether provides a way to apply pub/sub decorators through configuration instead of modifying source code.

Registry Configuration

The registry configuration allows you to specify which methods should be decorated with ether_pub and ether_sub. Here's an example:

registry:
  examples.external_class_integration.DataGenerator:
    methods:
      generate_data:
        ether_sub: {} # Empty dict for default settings
        ether_pub:
          topic: "data" # Publish to 'data' topic
  examples.external_class_integration.DataProcessor:
    methods:
      process_data:
        ether_sub:
          topic: "data" # Subscribe to 'data' topic
        ether_pub:
          topic: "processed_data" # Publish to 'processed_data' topic
  examples.external_class_integration.DataCollector:
    methods:
      collect_result:
        ether_sub:
          topic: "processed_data" # Subscribe to 'processed_data' topic
instances:
  generator:
    class_path: third_party_module.DataGenerator
    kwargs:
      process_id: 1
  processor2x:
    class_path: third_party_module.DataProcessor
    kwargs:
      multiplier: 2
  collector:
    class_path: third_party_module.DataCollector

Benefits

• No modification of source code required
• Works with third-party classes
• Configuration can be changed without code changes
• Same functionality as manual decoration

Real-World Example: Automated Lab Equipment

Here's how you might use Ether to automate a lab experiment:

class TemperatureSensor:
    @ether_pub(topic="DataLogger.log_temperature")
    def read_temperature(self) -> dict:
        temp = self._hardware.get_temperature()
        return {"temperature": temp, "timestamp": time.time()}

class DataLogger:
    @ether_sub()
    @ether_pub(topic="ExperimentController.check_temperature")
    def log_temperature(self, temperature: float, timestamp: float) -> dict:
        self._db.save_temperature(temperature, timestamp)
        return {"temperature": temperature, "timestamp": timestamp}

class ExperimentController:
    @ether_sub()
    def check_temperature(self, temperature: float, timestamp: float):
        if temperature > self.max_temp:
            self._safety_shutdown()