feature and tests

src/blueapi/service/interface.py

@@ -134,6 +134,20 @@ def get_device(name: str) -> DeviceModel:
     return DeviceModel.from_device(context().devices[name])
 
 
+def get_all_devices_using_interface(interface_name: str) -> list[DeviceModel]:
+    """Retrieve device by protocol from the BlueskyContext"""
+    interface_class = globals().get(interface_name)
+    if interface_class is None:
+        return []
+    devices = context().devices
+    results: list[DeviceModel] = []
+    for device in devices.values():
+        if isinstance(device, interface_class):
+            results.append(DeviceModel.from_device(device))
+
+    return results
+
+
 def submit_task(task: Task) -> str:
     """Submit a task to be run on begin_task"""
     return worker().submit_task(task)

src/blueapi/service/main.py

@@ -215,6 +215,18 @@ def get_device_by_name(name: str, runner: WorkerDispatcher = Depends(_runner)):
     return runner.run(interface.get_device, name)
 
 
+@router.get(
+    "/devices/",  # Endpoint to filter devices by protocol
+    response_model=list[str],
+)
+@start_as_current_span(TRACER, "protocol_name")
+def get_devices_by_protocol(
+    protocol_name: str, runner: WorkerDispatcher = Depends(_runner)
+):
+    """Retrieve all devices that implement the given protocol."""
+    return runner.run(get_devices_by_protocol(protocol_name))
+
+
 example_task = Task(name="count", params={"detectors": ["x"]})
 
 

tests/unit_tests/service/test_interface.py

@@ -151,6 +151,35 @@ def test_get_device(context_mock: MagicMock):
         assert interface.get_device("non_existing_device")
 
 
+@patch("blueapi.service.interface.context")
+def test_get_devices_by_protocol(context_mock: MagicMock):
+    context = BlueskyContext()
+    context.register_device(SynAxis(name="my_axis"))
+    context_mock.return_value = context
+
+    assert interface.get_all_devices_using_interface("Pausable") == [
+        DeviceModel(
+            name="my_axis",
+            protocols=[
+                "Checkable",
+                "HasHints",
+                "HasName",
+                "HasParent",
+                "Movable",
+                "Pausable",
+                "Readable",
+                "Stageable",
+                "Stoppable",
+                "Subscribable",
+                "Configurable",
+                "Triggerable",
+            ],
+        ),
+    ]
+
+    assert interface.get_all_devices_using_interface("non_existing_interface") == []
+
+
 @patch("blueapi.service.interface.context")
 def test_submit_task(context_mock: MagicMock):
     context = BlueskyContext()

tests/unit_tests/service/test_rest_api.py

@@ -7,6 +7,7 @@
 import pytest
 from fastapi import status
 from fastapi.testclient import TestClient
+from ophyd.sim import SynAxis
 from pydantic import BaseModel, ValidationError
 from pydantic_core import InitErrorDetails
 from super_state_machine.errors import TransitionError
@@ -160,6 +161,36 @@ class MyDevice:
     }
 
 
+def test_get_device_by_protocol(mock_runner: Mock, client: TestClient) -> None:
+    sya = SynAxis(name="my_axis")
+    mock_runner.run.return_value = DeviceModel.from_device(sya)
+    response = client.get("/devices?protocol_name=Pausable")
+
+    mock_runner.run.assert_called_once_with(test_get_device_by_protocol, "Pausable")
+    assert response.status_code == status.HTTP_200_OK
+    assert response.json() == {
+        "name": "my-device",
+        "protocols": ["HasName"],
+    }
+    assert response.json() == {
+        "name": "my_axis",
+        "protocols": [
+            "Checkable",
+            "HasHints",
+            "HasName",
+            "HasParent",
+            "Movable",
+            "Pausable",
+            "Readable",
+            "Stageable",
+            "Stoppable",
+            "Subscribable",
+            "Configurable",
+            "Triggerable",
+        ],
+    }
+
+
 def test_get_non_existent_device_by_name(mock_runner: Mock, client: TestClient) -> None:
     mock_runner.run.side_effect = KeyError("my-device")
     response = client.get("/devices/my-device")