SiLA 2 Integration

EOS provides built-in support for SiLA 2, enabling easier integration with SiLA-compliant instruments.

Overview

The SiLA integration allows you to:

• Host SiLA servers inside EOS devices

• Connect to external SiLA servers (manual or with autodiscovery)

• Call SiLA servers from tasks with automatic connection management

• Use LockController for exclusive device access (automatic)

Setup

Install the SiLA 2 Python package and supporting packages:

uv sync --group sila2

Hosting SiLA Servers

Host SiLA servers inside EOS devices using SilaDeviceMixin:

device.py

from eos.devices.base_device import BaseDevice
from eos.integrations.sila import SilaDeviceMixin
from your_package.sila import Server as YourSilaServer

class YourDevice(BaseDevice, SilaDeviceMixin):
    async def _initialize(self, init_parameters: dict[str, Any]) -> None:
        self.sila_add_server(
            name="server",
            server_class=YourSilaServer,
            port=init_parameters.get("sila_port", 0),  # 0 = auto-assign
            insecure=init_parameters.get("sila_insecure", True),
        )
        await self.sila_start_all()

    async def _cleanup(self) -> None:
        await self.sila_stop_all()

    async def _report(self) -> dict[str, Any]:
        return {**self.sila_get_status()}

device.yml

type: your_device
desc: Device that hosts a SiLA server

init_parameters:
  sila_port: 0
  sila_insecure: true

Connecting to External SiLA Servers

Manual Connection

Connect to a server at a known address:

self.sila_add_server_connection(
    name="external",
    address="192.168.1.100",
    port=50051,
    insecure=True,
)

Autodiscovery

Use SiLA autodiscovery to find servers on the network:

self.sila_add_server_connection(
    name="discovered",
    server_name="YourSilaServer",
    timeout=5.0,
    insecure=True,
)

Using Servers from Tasks

Connect to SiLA servers using SilaClientContext:

task.py

from eos.tasks.base_task import BaseTask
from eos.integrations.sila import SilaClientContext
from your_package.sila import Client as YourSilaClient

class YourTask(BaseTask):
    async def _execute(self, devices, parameters, resources):
        device = devices["your_device"]

        async with SilaClientContext.connect(device, YourSilaClient) as client:
            # Call commands
            response = client.YourFeature.YourCommand(Parameter=value)

            # Access properties
            property_value = client.YourFeature.YourProperty.get()

            return {"result": response.Result}, None, None

For devices with multiple servers, specify the server name:

async with SilaClientContext.connect(device, Client, "server_name") as client:
    ...

Long-Lived Connections

For connections that need to persist beyond a single context, use create_client():

# Create client without automatic closing
client = await SilaClientContext.create_client(device, YourSilaClient)

# Manually lock if needed
client.lock(timeout=300)

# Use the client
response = client.Feature.Command()

# Manually unlock and close when done
client.unlock()
client.close()

Calling Servers from Device Code

You can also call SiLA servers from within an EOS device:

from eos.devices.base_device import BaseDevice
from eos.integrations.sila import SilaDeviceMixin, SilaClientContext
from your_package.sila import Client as YourSilaClient

class YourDevice(BaseDevice, SilaDeviceMixin):
    async def _initialize(self, init_parameters: dict[str, Any]) -> None:
        # Connect to external SiLA server
        self.sila_add_server_connection(
            name="external",
            server_name="ExternalServer",
            insecure=True,
        )

        # Call the server during initialization
        async with SilaClientContext.connect(self, YourSilaClient) as client:
            self._initial_value = client.Feature.Property.get()

LockController Support

EOS automatically handles LockController when present:

• Auto-detection: Checks if server has LockController

• Auto-locking: Locks with unique UUID (default 60s)

• Metadata injection: Adds lock identifier to all calls

• Auto-retry: Waits up to 60s if locked

• Auto-unlock: Releases on context exit

Default Behavior

# Automatically locked for 60 seconds
async with SilaClientContext.connect(device, Client) as client:
    response = client.Feature.Command()

Custom Timeout

# Lock for 120 seconds
async with SilaClientContext.connect(device, Client, lock_timeout=120) as client:
    ...

Custom Retry Behavior

# Wait up to 30 seconds (60 retries × 0.5s) for lock
async with SilaClientContext.connect(
    device, Client,
    lock_timeout=120,
    lock_retry_delay=0.5,
    lock_max_retries=60
) as client:
    ...

Disable Auto-Locking

# No automatic locking
async with SilaClientContext.connect(device, Client, lock_timeout=None) as client:
    ...

Manual Lock Control

async with SilaClientContext.connect(device, Client, lock_timeout=None) as client:
    client.lock(timeout=90)  # Lock with auto-generated UUID
    response = client.Feature.Command()
    client.unlock()