Make sure initial values are respected in CA transport (#257)

Author: jsouter

pyproject.toml

@@ -50,6 +50,7 @@ dev = [
     "pytest-cov",
     "pytest-mock",
     "pytest-asyncio",
+    "pytest-forked",
     "pytest-markdown-docs",
     "ruff",
     "sphinx-autobuild",

src/fastcs/transport/epics/ca/util.py

@@ -1,4 +1,5 @@
 from dataclasses import asdict
+from typing import Any
 
 from softioc import builder
 
@@ -45,10 +46,19 @@
 
 def record_metadata_from_attribute(
     attribute: Attribute[T],
-) -> dict[str, str | None]:
+) -> dict[str, Any]:
     """Converts attributes on the `Attribute` to the
     field name/value in the record metadata."""
-    return {"DESC": attribute.description}
+    metadata: dict[str, Any] = {"DESC": attribute.description}
+    initial = None
+    match attribute:
+        case AttrR():
+            initial = attribute.get()
+        case AttrW():
+            initial = attribute.datatype.initial_value
+    if initial is not None:
+        metadata["initial_value"] = cast_to_epics_type(attribute.datatype, initial)
+    return metadata
 
 
 def record_metadata_from_datatype(
@@ -120,7 +130,7 @@ def cast_from_epics_type(datatype: DataType[T], value: object) -> T:
             raise ValueError(f"Unsupported datatype {datatype}")
 
 
-def cast_to_epics_type(datatype: DataType[T], value: T) -> object:
+def cast_to_epics_type(datatype: DataType[T], value: T) -> Any:
     """Casts from an attribute's datatype to an EPICS datatype."""
     match datatype:
         case Enum():

tests/transport/epics/ca/test_initial_value.py

@@ -0,0 +1,114 @@
+import asyncio
+import enum
+
+import numpy as np
+import pytest
+
+import fastcs.transport.epics.ca.ioc as ca_ioc
+from fastcs.attributes import AttrR, AttrRW, AttrW
+from fastcs.controller import Controller
+from fastcs.datatypes import Bool, Enum, Float, Int, String, Waveform
+from fastcs.launch import FastCS
+from fastcs.transport.epics.ca.transport import EpicsCATransport
+from fastcs.transport.epics.options import EpicsIOCOptions
+
+
+class InitialEnum(enum.Enum):
+    A = 0
+    B = 1
+    C = 2
+
+
+class InitialValuesController(Controller):
+    int = AttrRW(Int(), initial_value=4)
+    float = AttrRW(Float(), initial_value=3.1)
+    bool = AttrRW(Bool(), initial_value=True)
+    enum = AttrRW(Enum(InitialEnum), initial_value=InitialEnum.B)
+    str = AttrRW(String(), initial_value="initial")
+    waveform = AttrRW(
+        Waveform(np.int64, shape=(10,)),
+        initial_value=np.array(range(10), dtype=np.int64),
+    )
+    int_r = AttrR(Int(), initial_value=5)
+    float_r = AttrR(Float(), initial_value=4.1)
+    bool_r = AttrR(Bool(), initial_value=False)
+    enum_r = AttrR(Enum(InitialEnum), initial_value=InitialEnum.C)
+    str_r = AttrR(String(), initial_value="initial_r")
+    waveform_r = AttrR(
+        Waveform(np.int64, shape=(10,)),
+        initial_value=np.array(range(10, 20), dtype=np.int64),
+    )
+    int_w = AttrW(Int())
+    float_w = AttrW(Float())
+    bool_w = AttrW(Bool())
+    enum_w = AttrW(Enum(InitialEnum))
+    str_w = AttrW(String())
+    waveform_w = AttrW(Waveform(np.int64, shape=(10,)))
+
+
+@pytest.mark.forked
+@pytest.mark.asyncio
+async def test_initial_values_set_in_ca(mocker):
+    pv_prefix = "SOFTIOC_INITIAL_DEVICE"
+
+    loop = asyncio.get_event_loop()
+    controller = InitialValuesController()
+    fastcs = FastCS(
+        controller,
+        [EpicsCATransport(ca_ioc=EpicsIOCOptions(pv_prefix=pv_prefix))],
+        loop,
+    )
+
+    record_spy = mocker.spy(ca_ioc, "_make_record")
+
+    task = asyncio.create_task(fastcs.serve(interactive=False))
+    try:
+        async with asyncio.timeout(3):
+            while not record_spy.spy_return_list:
+                await asyncio.sleep(0)
+
+        initial_values = {
+            wrapper.name: wrapper.get() for wrapper in record_spy.spy_return_list
+        }
+        for name, value in {
+            "SOFTIOC_INITIAL_DEVICE:Bool": 1,
+            "SOFTIOC_INITIAL_DEVICE:BoolR": 0,
+            "SOFTIOC_INITIAL_DEVICE:BoolW": 0,
+            "SOFTIOC_INITIAL_DEVICE:Bool_RBV": 1,
+            "SOFTIOC_INITIAL_DEVICE:Enum": 1,
+            "SOFTIOC_INITIAL_DEVICE:EnumR": 2,
+            "SOFTIOC_INITIAL_DEVICE:EnumW": 0,
+            "SOFTIOC_INITIAL_DEVICE:Enum_RBV": 1,
+            "SOFTIOC_INITIAL_DEVICE:Float": 3.1,
+            "SOFTIOC_INITIAL_DEVICE:FloatR": 4.1,
+            "SOFTIOC_INITIAL_DEVICE:FloatW": 0.0,
+            "SOFTIOC_INITIAL_DEVICE:Float_RBV": 3.1,
+            "SOFTIOC_INITIAL_DEVICE:Int": 4,
+            "SOFTIOC_INITIAL_DEVICE:IntR": 5,
+            "SOFTIOC_INITIAL_DEVICE:IntW": 0,
+            "SOFTIOC_INITIAL_DEVICE:Int_RBV": 4,
+            "SOFTIOC_INITIAL_DEVICE:Str": "initial",
+            "SOFTIOC_INITIAL_DEVICE:StrR": "initial_r",
+            "SOFTIOC_INITIAL_DEVICE:StrW": "",
+            "SOFTIOC_INITIAL_DEVICE:Str_RBV": "initial",
+            "SOFTIOC_INITIAL_DEVICE:Waveform": [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+            "SOFTIOC_INITIAL_DEVICE:WaveformR": [
+                10,
+                11,
+                12,
+                13,
+                14,
+                15,
+                16,
+                17,
+                18,
+                19,
+            ],
+            "SOFTIOC_INITIAL_DEVICE:WaveformW": 10 * [0],
+            "SOFTIOC_INITIAL_DEVICE:Waveform_RBV": [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+        }.items():
+            assert np.array_equal(value, initial_values[name])
+    except Exception as e:
+        raise e
+    finally:
+        task.cancel()

tests/transport/epics/pva/test_p4p.py

@@ -390,7 +390,7 @@ class SomeController(Controller):
         }
 
 
-def test_more_exotic_dataypes():
+def test_more_exotic_datatypes():
     table_columns: list[tuple[str, DTypeLike]] = [
         ("A", "i"),
         ("B", "i"),