app/backend/tests/flow/test_device_node.py

"""A device node: never run by the engine, degraded while its device is away."""

import asyncio
from pathlib import Path

from fluksio.flow.alerts import Alert, AlertManager, AlertsConfig, Channel, Rule
from fluksio.flow.controller import HEALTH_FLOOR, FlowController
from fluksio.flow.devices import presence
from fluksio.flow.events import EventBus
from fluksio.flow.messages import DType, MessageSpec
from fluksio.flow.schemas import FlowDef, FlowInput, NodeDef
from fluksio.flow.store import FlowStore


def _controller(tmp_path: Path) -> FlowController:
    store = FlowStore(tmp_path / "flows")
    store.write_flow(
        FlowDef(
            name="hall",
            inputs=[
                FlowInput(spec=MessageSpec(name="level", dtype=DType.INT), initial=50)
            ],
            nodes=[
                NodeDef(
                    id="panel",
                    type="device",
                    params={"device": "wall"},
                    provides=[
                        MessageSpec(name="bell", port="gpio.4", dtype=DType.BOOL)
                    ],
                    requires=[
                        MessageSpec(
                            name="level",
                            port="backlight",
                            dtype=DType.INT,
                            trigger=False,
                        )
                    ],
                ),
                NodeDef(
                    id="ring",
                    type="change",
                    requires=[MessageSpec(name="bell", dtype=DType.BOOL)],
                    provides=[MessageSpec(name="rung", dtype=DType.BOOL)],
                ),
            ],
        )
    )
    return FlowController(store)


def test_the_engine_never_runs_a_device_node(tmp_path: Path) -> None:
    controller = _controller(tmp_path)
    asyncio.run(controller.reload())
    assert controller.issues == []
    node = controller.get_node("hall.panel")
    assert node is not None and node.passive
    ran: list[object] = []
    node.f = lambda **kwargs: ran.append(kwargs)  # type: ignore[method-assign]

    # The message its out port follows changes, and a manual run of the flow.
    controller.publish_message("hall.level", 80)
    controller.run_flow("hall")
    assert ran == []

    # What the device publishes on its in port runs what reads it.
    controller.publish_message("hall.bell", True)
    assert controller.values("hall")["hall.rung"]["value"] is True
    asyncio.run(controller._teardown())


def test_a_device_node_is_degraded_while_its_device_is_away(tmp_path: Path) -> None:
    controller = _controller(tmp_path)

    async def scenario() -> list[tuple[str, str | None]]:
        await controller.reload()
        entry = controller.loaded["hall.panel"]
        seen = [(entry.health, entry.health_detail)]
        presence.opened("wall")
        seen.append((entry.health, entry.health_detail))
        presence.closed("wall")
        seen.append((entry.health, entry.health_detail))
        await controller._teardown()
        # Stopped, it no longer follows the device.
        presence.opened("wall")
        seen.append((entry.health, entry.health_detail))
        presence.closed("wall")
        return seen

    # Degraded, not down: a switched-off panel is a warning, never a fault.
    assert asyncio.run(scenario()) == [
        ("degraded", "Offline"),
        ("ok", None),
        ("degraded", "Offline"),
        ("degraded", "Offline"),
    ]
    presence.forget("wall")


def test_an_offline_device_is_a_warning_not_a_fault(tmp_path: Path) -> None:
    controller = _controller(tmp_path)

    async def scenario() -> list:
        await controller.reload()
        # Past the floor that holds back a device rebooting.
        controller.loaded["hall.panel"].health_since -= 3600
        found = (
            controller.unhealthy_nodes(),
            [e.id for e in controller.unhealthy_nodes(health="degraded")],
            [(i.code, i.advisory) for i in controller.flow_issues("hall")],
        )
        await controller._teardown()
        return list(found)

    assert asyncio.run(scenario()) == [
        [],
        ["hall.panel"],
        [("node_degraded", True)],
    ]


def test_a_device_away_after_a_restart_alerts_nobody(tmp_path: Path) -> None:
    """No push, and degraded on screen only once the floor has passed.

    A restart starts every device node without its device, which comes back
    within seconds, and a rule on every node's health is what sends phones a
    push.
    """
    controller = _controller(tmp_path)
    events: list[dict] = []
    original = controller._publish
    controller._publish = lambda event: (events.append(event), original(event))  # type: ignore[method-assign]
    sent: list[Alert] = []
    alerts = AlertManager(
        EventBus(),
        AlertsConfig(
            channels=[Channel(name="phone", kind="ntfy", config={"topic": "t"})],
            rules=[Rule(events=["node_health"], channels=["phone"])],
        ),
    )

    async def capture(channel: Channel, alert: Alert) -> None:
        sent.append(alert)

    alerts.send = capture  # type: ignore[method-assign]

    async def scenario() -> list[list[str]]:
        await controller.reload()  # the restart: the device is not back yet
        surfaced = [[e.id for e in controller.unhealthy_nodes(health="degraded")]]
        presence.opened("wall")
        presence.closed("wall")  # and it drops again
        surfaced.append([e.id for e in controller.unhealthy_nodes(health="degraded")])
        controller.loaded["hall.panel"].health_since -= HEALTH_FLOOR
        surfaced.append([e.id for e in controller.unhealthy_nodes(health="degraded")])
        for event in events:
            await alerts.handle(event)
        await controller._teardown()
        return surfaced

    assert asyncio.run(scenario()) == [[], [], ["hall.panel"]]
    assert [e["health"] for e in events if e["type"] == "node_health"] == [
        "degraded",
        "ok",
        "degraded",
    ]
    assert sent == []
    presence.forget("wall")