runtime: increment trigger/service counters on the bus

src/HomeAssistant/Runtime.hs

@@ -82,12 +82,13 @@ runController rootDir bus (Controller name machine _enabled) = do
 defaultMain :: IO ()
 defaultMain = withSocketsDo $ do
   severity <- maybe InfoS (const DebugS) <$> lookupEnv "HA_DEBUG"
-  withBus severity $ \bus -> do
+  store <- System.Metrics.newStore
+  System.Metrics.registerGcMetrics store
+  appMetrics <- HomeAssistant.Runtime.Metrics.registerAppMetrics store
+  withBus severity appMetrics $ \bus -> do
     token <- getEnv "HA_TOKEN"
     host <- getEnv "HA_HOST"
     rootPath <- fromMaybe "/tmp/" <$> lookupEnv "HA_LIB_DIR"
-    store <- System.Metrics.newStore
-    System.Metrics.registerGcMetrics store
     rrdPath <- fromMaybe "hass-controller.rrd" <$> lookupEnv "HA_RRD_PATH"
     rrdtool <- fromMaybe "rrdtool" <$> lookupEnv "HA_RRDTOOL"
     let active = [c | c@(Controller _ _ True) <- controllers]

src/HomeAssistant/Runtime/Bus.hs

@@ -6,6 +6,8 @@ module HomeAssistant.Runtime.Bus
   , CallIdGen(..)
   , mkCallIdGen
   , withBus
+  , recordInbound
+  , recordOutbound
   , channelHassEval
   ) where
 
@@ -21,10 +23,12 @@ import Control.Concurrent.STM
 import Data.Aeson (Value)
 import Data.IORef (atomicModifyIORef', newIORef)
 import HomeAssistant.Controller (HASSEff (..), Service)
+import HomeAssistant.Runtime.Metrics (AppMetrics (..))
 import Network.WebSockets (Connection)
 import Katip (LogEnv, closeScribes, mkHandleScribe, ColorStrategy (..), permitItem, Severity (..), Verbosity (V2), registerScribe, defaultScribeSettings, initLogEnv, ls, sl, logFM, katipAddContext, KatipContext)
 import Control.Exception (bracket)
 import System.IO (stdout)
+import System.Metrics.Counter (inc)
 import Data.UUID (toText)
 import AFRP (Request(..), Event(..))
 import Control.Monad.IO.Class (MonadIO, liftIO)
@@ -38,10 +42,11 @@ data Bus = Bus
   , busConn     :: TVar (Maybe Connection)
   , busGen      :: CallIdGen
   , busLogEnv   :: LogEnv
+  , busMetrics  :: AppMetrics
   }
 
-withBus :: Severity -> (Bus -> IO a) -> IO a
-withBus severity callback = do
+withBus :: Severity -> AppMetrics -> (Bus -> IO a) -> IO a
+withBus severity metrics callback = do
   handleScribe <- mkHandleScribe ColorIfTerminal stdout (permitItem severity) V2
   let makeLogEnv = registerScribe "stdout" handleScribe defaultScribeSettings =<< initLogEnv "hass-controller" "production"
   -- closeScribes will stop accepting new logs, flush existing ones and clean up resources
@@ -52,8 +57,15 @@ withBus severity callback = do
           <*> newTVarIO Nothing
           <*> mkCallIdGen 0
           <*> pure le
+          <*> pure metrics
     callback bus
 
+recordInbound :: Bus -> IO ()
+recordInbound bus = inc (amTriggersIn (busMetrics bus))
+
+recordOutbound :: Bus -> IO ()
+recordOutbound bus = inc (amServicesOut (busMetrics bus))
+
 channelHassEval :: (MonadIO m, KatipContext m) => Bus -> HASSEff a -> m a
 channelHassEval bus = \case
   CallService req svc -> katipAddContext (sl "traceId" (toText (requestTraceId req))) $ do

src/HomeAssistant/Runtime/Connection.hs

@@ -96,7 +96,9 @@ receiveLoop bus conn = forever $ do
     Left () -> atomically $ writeTChan (busInbound bus) Tick
     Right msg -> case eitherDecode msg of
       Left err -> putStrLn $ "[reader] skipping undecodable message: " <> err
-      Right v  -> atomically $ writeTChan (busInbound bus) (Event v)
+      Right v  -> do
+        recordInbound bus
+        atomically $ writeTChan (busInbound bus) (Event v)
 
 receiveJSON :: WS.Connection -> IO Value
 receiveJSON conn = do
@@ -128,6 +130,7 @@ sendWithId bus conn request svc = do
   let textData = encode $ encodeService callId svc
   runKatipContextT (busLogEnv bus) (sl "traceId" (toText (requestTraceId request))) "connection" $
     logFM DebugS (ls textData)
+  recordOutbound bus
   WS.sendTextData conn textData
 
 writerAction :: Bus -> IO Void

test/BusSpec.hs

@@ -10,16 +10,19 @@ import Control.Concurrent.STM
   , writeTChan
   )
 import Data.Aeson (Value (..))
+import qualified Data.HashMap.Strict as HM
 import Data.Time (UTCTime (..), utc)
 import Data.UUID (nil)
 import HomeAssistant.Controller (HASSEff (..), Service (..), Target(..))
 import HomeAssistant.Runtime.Bus
+import HomeAssistant.Runtime.Metrics (registerAppMetrics)
 import Katip (Namespace (Namespace), runKatipContextT, Severity (..))
+import qualified System.Metrics as Metrics
 import Test.Hspec
 
 spec :: Spec
 spec = describe "Bus" $ do
-  it "broadcasts inbound messages to every dup'd channel in order" $ withBus InfoS $ \bus -> do
+  it "broadcasts inbound messages to every dup'd channel in order" $ withTestBus $ \bus -> do
     p1 <- atomically $ dupTChan (busInbound bus)
     p2 <- atomically $ dupTChan (busInbound bus)
     atomically $ writeTChan (busInbound bus) (Event (Number 1))
@@ -29,7 +32,7 @@ spec = describe "Bus" $ do
     r1 `shouldBe` (Event (Number 1), Event (Number 2))
     r2 `shouldBe` (Event (Number 1), Event (Number 2))
 
-  it "channelHassEval writes CallService to the outbound channel" $ withBus InfoS $ \bus -> do
+  it "channelHassEval writes CallService to the outbound channel" $ withTestBus $ \bus -> do
     let req = Request (UTCTime (toEnum 0) 0) utc nil
         svc = Service "light" "turn_on" Nothing [EntityId "light.bedroom_masse"]
     runKatipContextT (busLogEnv bus) () (Namespace ["test"]) $
@@ -43,3 +46,21 @@ spec = describe "Bus" $ do
     a <- generateCallId gen
     b <- generateCallId gen
     (a, b) `shouldBe` (1, 2)
+
+  describe "recordInbound / recordOutbound" $ do
+    it "increments the trigger and service counters" $ do
+      store <- Metrics.newStore
+      m <- registerAppMetrics store
+      withBus InfoS m $ \bus -> do
+        recordInbound bus
+        recordInbound bus
+        recordOutbound bus
+        sample <- Metrics.sampleAll store
+        HM.lookup "hass.trigger.in" sample `shouldBe` Just (Metrics.Counter 2)
+        HM.lookup "hass.service.out" sample `shouldBe` Just (Metrics.Counter 1)
+
+withTestBus :: (Bus -> IO a) -> IO a
+withTestBus action = do
+  store <- Metrics.newStore
+  m <- registerAppMetrics store
+  withBus InfoS m action