On Thu, Jul 30, 2015 at 12:11:59PM +0200, 'Klaus Aehlig' via ganeti-devel wrote:
Generate lenses for the MemoryState data type. Then, instead
of using selector and setter, use the lens to focus on the changed
part.
Signed-off-by: Klaus Aehlig <[email protected]>
---
src/Ganeti/MaintD/MemoryState.hs | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/src/Ganeti/MaintD/MemoryState.hs b/src/Ganeti/MaintD/MemoryState.hs
index f3b53d9..458b611 100644
--- a/src/Ganeti/MaintD/MemoryState.hs
+++ b/src/Ganeti/MaintD/MemoryState.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE TemplateHaskell #-}
+
{-| Memory copy of the state of the maintenance daemon.
While the autoritative state of the maintenance daemon is
@@ -52,11 +54,13 @@ module Ganeti.MaintD.MemoryState
) where
import Control.Monad.IO.Class (liftIO)
-import Data.IORef (IORef, atomicModifyIORef)
+import Data.IORef (IORef)
import Ganeti.BasicTypes (ResultT, withErrorT)
+import Ganeti.Lens (makeCustomLenses)
import Ganeti.Types (JobId)
import Ganeti.Utils (ordNub)
+import Ganeti.Utils.IORef (atomicModifyWithLens_)
import Ganeti.WConfd.Client ( runNewWConfdClient, maintenanceJobs, runModifyRpc
, clearMaintdJobs, appendMaintdJobs
, maintenanceEvacuated, addMaintdEvacuated
@@ -69,6 +73,8 @@ data MemoryState = MemoryState
, msEvacuated :: [ String ]
}
+$(makeCustomLenses ''MemoryState)
+
-- | Inital state of the in-memory copy. All parts will be updated
-- before use, after one round at the latest this copy is up to date.
emptyMemoryState :: MemoryState
@@ -81,40 +87,37 @@ emptyMemoryState = MemoryState { msJobs = []
getJobs :: IORef MemoryState -> ResultT String IO [JobId]
getJobs memstate = do
jobs <- withErrorT show $ runNewWConfdClient maintenanceJobs
- liftIO . atomicModifyIORef memstate $ \ s -> (s { msJobs = jobs }, ())
+ liftIO . atomicModifyWithLens_ memstate msJobsL $ const jobs
return jobs
-- | Reset the list of active jobs.
clearJobs :: IORef MemoryState -> IO ()
clearJobs memstate = do
runModifyRpc clearMaintdJobs
- atomicModifyIORef memstate $ \ s -> ( s { msJobs = [] }, ())
+ atomicModifyWithLens_ memstate msJobsL $ const []
-- | Append jobs to the list of active jobs, if not present already
appendJobs :: IORef MemoryState -> [JobId] -> IO ()
appendJobs memstate jobs = do
runModifyRpc $ appendMaintdJobs jobs
- atomicModifyIORef memstate
- $ \ s -> ( s { msJobs = ordNub $ msJobs s ++ jobs }, ())
+ atomicModifyWithLens_ memstate msJobsL $ ordNub . (++ jobs)
-- | Get the list of recently evacuated instances from the authoritative
-- copy and update the in-memory state.
getEvacuated :: IORef MemoryState -> ResultT String IO [String]
getEvacuated memstate = do
evac <- withErrorT show $ runNewWConfdClient maintenanceEvacuated
- liftIO . atomicModifyIORef memstate $ \s -> (s { msEvacuated = evac }, ())
+ liftIO . atomicModifyWithLens_ memstate msEvacuatedL $ const evac
return evac
-- | Add names to the list of recently evacuated instances.
addEvacuated :: IORef MemoryState -> [String] -> IO ()
addEvacuated memstate names = do
runModifyRpc $ addMaintdEvacuated names
- atomicModifyIORef memstate
- $ \s -> (s { msEvacuated = ordNub $ msEvacuated s ++ names }, ())
+ atomicModifyWithLens_ memstate msEvacuatedL $ ordNub . (++ names)
-- | Remove a name from the list of recently evacuated instances.
rmEvacuated :: IORef MemoryState -> String -> IO ()
rmEvacuated memstate name = do
runModifyRpc $ rmMaintdEvacuated name
- atomicModifyIORef memstate
- $ \s -> (s { msEvacuated = filter (/= name) $ msEvacuated s }, ())
+ atomicModifyWithLens_ memstate msEvacuatedL $ filter (/= name)
--
2.5.0.rc2.392.g76e840b
LGTM, thanks
