Tracing

src/HomeAssistant/Controller.hs

@@ -25,10 +25,11 @@ module HomeAssistant.Controller
   , Presence(..)
   , presence
   , debug
+  , traceEvent
   , switch
   ) where
 
-import AFRP (Mealy, eff, Event(..), hold, events, changes, filterA, (>>|), toEvent)
+import AFRP (Mealy (..), eff, Event(..), hold, events, changes, filterA, (>>|), toEvent, Request)
 import Control.Arrow (Arrow(..), returnA)
 import Control.Category ((>>>))
 import Data.Aeson (Value)
@@ -49,6 +50,7 @@ data Service = Service
 data HASSEff a where
   CallService :: Service -> HASSEff ()
   Debug :: Show a => a -> HASSEff ()
+  Trace :: Show a => Request -> a -> HASSEff ()
 
 type HASS a b = Mealy HASSEff a b
 
@@ -60,6 +62,11 @@ debug = proc x -> do
   eff Debug -< x
   returnA -< x
 
+traceEvent :: Show a => HASS (Event a) (Event a)
+traceEvent = Mealy $ \nt req -> \case
+  Event a -> nt (Trace req a) >>= \() -> pure (Event a, traceEvent)
+  Tick -> pure (Tick, traceEvent)
+
 ruuviTemperatures :: Mealy eff (Event Value) Double
 ruuviTemperatures = entityRead @Double "sensor.ruuvitag_b168_temperature" >>> hold 0