diff --git a/LICENSE b/LICENSE --- a/LICENSE +++ b/LICENSE @@ -1,674 +1,30 @@ - GNU GENERAL PUBLIC LICENSE - Version 3, 29 June 2007 - - Copyright (C) 2007 Free Software Foundation, Inc. - Everyone is permitted to copy and distribute verbatim copies - of this license document, but changing it is not allowed. - - Preamble - - The GNU General Public License is a free, copyleft license for -software and other kinds of works. - - The licenses for most software and other practical works are designed -to take away your freedom to share and change the works. By contrast, -the GNU General Public License is intended to guarantee your freedom to -share and change all versions of a program--to make sure it remains free -software for all its users. We, the Free Software Foundation, use the -GNU General Public License for most of our software; it applies also to -any other work released this way by its authors. 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If this is what you want to do, use the GNU Lesser General -Public License instead of this License. But first, please read -. +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/README.md b/README.md deleted file mode 100644 --- a/README.md +++ /dev/null @@ -1,71 +0,0 @@ -See [the demo](https://github.com/jamesdabbs/yesod-worker-demo) for an example site with workers set up. - -# Usage - -## Define your Job type - -``` --- Up to you where this goes, so long as it's importable -data AppJob = CountJob Int | UserJob -``` - -## Include a queue in your foundation data type - -``` --- Foundation.hs -import Yesod.Worker (JobQueue, YesodWorker(..), defaultRunW) - -data App = App - { settings :: AppConfig DefaultEnv Extra - ... - , appQueue :: JobQueue AppJob - } -``` - -## Specify how to run your jobs -``` --- Foundation.hs (provided you don't want to orphan the instance) -instance YesodWorker App where - type Job = AppJob - queue = appQueue - runW = defaultRunW persistConfig connPool - - -- Dummy implementations, obviously these would depend on your app - perform (CountJob n) = void . forM [1..n] $ \k -> do - lift . putStrLn . show $ k - lift $ threadDelay 1000000 - perform UserJob = do - -- Note that you can run SQL using the `runW` helper - n <- runW $ count ([] :: [Filter User]) - lift . putStrLn $ "There are " ++ (show n) ++ " users" -``` - -## Start the queue on app boot -``` --- Application.hs -import Yesod.Worker (emptyQueue, spawnWorkers) - -makeFoundation conf = do - ... - q <- emptyQueue - let foundation = App conf ... q - spawnWorkers foundation - ... -``` - -## Queue up a job -``` -import Yesod.Worker (enqueue) - -getWhateverR = do - enqueue $ CountJob 10 - ... -``` - -# TODO - -* Simplify installation? -* Include job subsite for viewing queue and worker status -* Swappable queue backends (for e.g. Redis) -* Improve error handling / job failures / worker restarts -* Allow multiple queues with customizable priority diff --git a/Yesod/Worker.hs b/Yesod/Worker.hs deleted file mode 100644 --- a/Yesod/Worker.hs +++ /dev/null @@ -1,68 +0,0 @@ -module Yesod.Worker -( defaultRunW -, enqueue -, emptyQueue -, getYesodW -, JobQueue -, spawnWorkers -, WorkerT -, YesodWorker (..) -) where - -import Prelude - -import Yesod -import Yesod.Worker.Queue -import Yesod.Worker.Types - -import Control.Concurrent (forkIO, threadDelay) -import Control.Monad (forever, liftM, replicateM_) -import Control.Monad.Trans.Resource (runResourceT, withInternalState) - - -askWorkerEnv :: MonadWorker m => m (RunWorkerEnv (WorkerSite m)) -askWorkerEnv = liftWorkerT $ WorkerT $ return . workerEnv - --- | Get the master site application argument. -getYesodW :: MonadWorker m => m (WorkerSite m) -getYesodW = rweSite `liftM` askWorkerEnv - --- | Provides the default `runW` implementation for running SQL queries inside a `Worker` -defaultRunW :: (PersistConfig c, MonadWorker m, MonadBaseControl IO m) => - (WorkerSite m -> c) - -> (WorkerSite m -> PersistConfigPool c) - -> PersistConfigBackend c m b - -> m b -defaultRunW persistConfig connPool f = do - app <- getYesodW - runPool (persistConfig app) f (connPool app) - - -runWorker :: (Yesod site) => site -> WorkerT site IO a -> IO a -runWorker site worker = runResourceT . withInternalState $ \resState -> do - logger <- makeLogger site - let rwe = RunWorkerEnv - { rweSite = site - , rweLog = messageLoggerSource site logger - } - let wd = WorkerData - { workerResource = resState - , workerEnv = rwe - } - -- FIXME: catch and handle errors (see unHandlerT) - unWorkerT worker wd - --- | Spawns a number of workers which will consume from the application queue --- performing jobs as they are popped. -spawnWorkers :: YesodWorker site => site -> IO () -spawnWorkers site = replicateM_ (workerCount site) . forkIO . forever $ do - mj <- dequeueJob $ queue site - case mj of - Just job -> runWorker site $ perform job - Nothing -> threadDelay 1000000 - --- | Add a job to the site queue from within a Handler -enqueue :: YesodWorker site => Job -> HandlerT site IO () -enqueue job = do - app <- getYesod - liftIO $ enqueueJob (queue app) job diff --git a/Yesod/Worker/Queue.hs b/Yesod/Worker/Queue.hs deleted file mode 100644 --- a/Yesod/Worker/Queue.hs +++ /dev/null @@ -1,36 +0,0 @@ -module Yesod.Worker.Queue -( enqueueJob -, dequeueJob -, emptyQueue -) where - -import Prelude -import Yesod.Worker.Types - -import Control.Concurrent.STM -import qualified Data.Sequence as S - -enqueue :: S.Seq a -> a -> S.Seq a -enqueue = (S.|>) - -dequeue :: S.Seq a -> Maybe (a, S.Seq a) -dequeue s = case S.viewl s of - x S.:< xs -> Just (x, xs) - _ -> Nothing - - --- | An empty queue, suitable for initializing the app queue at boot -emptyQueue :: IO (JobQueue a) -emptyQueue = atomically $ newTVar S.empty - -enqueueJob :: JobQueue a -> a -> IO () -enqueueJob qvar j = atomically . modifyTVar qvar $ \v -> enqueue v j - -dequeueJob :: JobQueue a -> IO (Maybe a) -dequeueJob qvar = atomically $ do - q <- readTVar qvar - case dequeue q of - Just (x,xs) -> do - writeTVar qvar xs - return $ Just x - Nothing -> return Nothing diff --git a/Yesod/Worker/Types.hs b/Yesod/Worker/Types.hs deleted file mode 100644 --- a/Yesod/Worker/Types.hs +++ /dev/null @@ -1,102 +0,0 @@ -{-# LANGUAGE ConstraintKinds, FlexibleInstances, UndecidableInstances #-} -module Yesod.Worker.Types where - -import Prelude -import Yesod - -import Control.Applicative (Applicative (..)) -import Control.Concurrent.STM (TVar) -import Control.Monad (liftM, ap) -import Control.Monad.Logger (LogSource, MonadLogger (..)) -import Control.Monad.Trans.Control (MonadBaseControl (..)) -import Control.Monad.Trans.Resource (InternalState, runInternalState, MonadThrow (..), monadThrow, MonadResourceBase) -import qualified Data.Sequence as S -import Database.Persist.Sql (SqlPersistT) -import Language.Haskell.TH.Syntax (Loc) -import System.Log.FastLogger (LogStr, toLogStr) - - -type JobQueue a = TVar (S.Seq a) - --- | Typeclass for customizing Worker settings -class Yesod site => YesodWorker site where - -- | Your applications job type - type Job - - -- | How to retreive the application queue - queue :: site -> JobQueue Job - - -- | Number of concurrent workers - workerCount :: site -> Int - workerCount _ = 3 - - -- | How to execute each job - perform :: Job -> WorkerT site IO () - - -- TODO: Allow different PersistBackends - -- | Helper for running SQL queries inside a Worker - runW :: SqlPersistT (WorkerT site IO) a -> WorkerT site IO a - - -data RunWorkerEnv site = RunWorkerEnv - { rweSite :: !site - , rweLog :: !(Loc -> LogSource -> LogLevel -> LogStr -> IO ()) - -- , rheOnError :: !(ErrorResponse -> YesodApp) - } - -data WorkerData site = WorkerData - { workerResource :: !InternalState - , workerEnv :: !(RunWorkerEnv site) - } - -newtype WorkerT site m a = WorkerT - { unWorkerT :: WorkerData site -> m a - } - - -instance MonadTrans (WorkerT site) where - lift = WorkerT . const - -instance Monad m => Functor (WorkerT site m) where - fmap = liftM - -instance Monad m => Applicative (WorkerT site m) where - pure = return - (<*>) = ap - -instance MonadIO m => MonadIO (WorkerT site m) where - liftIO = lift . liftIO - -instance MonadBase b m => MonadBase b (WorkerT site m) where - liftBase = lift . liftBase - --- TODO: absorb the instance declarations below -instance Monad m => Monad (WorkerT site m) where - return = WorkerT . const . return - WorkerT x >>= f = WorkerT $ \r -> x r >>= \x' -> unWorkerT (f x') r - -instance MonadBaseControl b m => MonadBaseControl b (WorkerT site m) where - data StM (WorkerT site m) a = StH (StM m a) - liftBaseWith f = WorkerT $ \reader -> - liftBaseWith $ \runInBase -> - f $ liftM StH . runInBase . (\(WorkerT r) -> r reader) - restoreM (StH base) = WorkerT $ const $ restoreM base - -instance MonadThrow m => MonadThrow (WorkerT site m) where - throwM = lift . monadThrow - -instance (MonadIO m, MonadBase IO m, MonadThrow m) => MonadResource (WorkerT site m) where - liftResourceT f = WorkerT $ \hd -> liftIO $ runInternalState f (workerResource hd) - -instance MonadIO m => MonadLogger (WorkerT site m) where - monadLoggerLog a b c d = WorkerT $ \hd -> - liftIO $ rweLog (workerEnv hd) a b c (toLogStr d) - -class MonadResource m => MonadWorker m where - type WorkerSite m - liftWorkerT :: WorkerT (WorkerSite m) IO a -> m a - -instance MonadResourceBase m => MonadWorker (WorkerT site m) where - type WorkerSite (WorkerT site m) = site - liftWorkerT (WorkerT f) = WorkerT $ liftIO . f -{-# RULES "liftWorkerT (WorkerT site IO)" liftWorkerT = id #-} diff --git a/src/Yesod/Worker.hs b/src/Yesod/Worker.hs new file mode 100644 --- /dev/null +++ b/src/Yesod/Worker.hs @@ -0,0 +1,58 @@ +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE MultiParamTypeClasses #-} +{-# LANGUAGE OverloadedStrings #-} +{-# LANGUAGE RecordWildCards #-} +{-# LANGUAGE TemplateHaskell #-} +module Yesod.Worker + ( Worker(..) + , Workers + , YesodWorker(..) + , bootWorkers + , newWorkers + , concurrency + , register + , enqueue + , enqueueAt + , enqueueIn + ) where + +import Keenser hiding (enqueue, enqueueAt, enqueueIn) +import Yesod.Worker.Site +import Yesod.Worker.Types +import Yesod.Worker.Util +import Yesod + +import Control.Concurrent +import Control.Monad +import Database.Redis + +instance YesodWorker master => YesodSubDispatch Workers (HandlerT master IO) where + yesodSubDispatch = $(mkYesodSubDispatch resourcesWorkers) + +newWorkers :: IO Workers +newWorkers = Workers <$> newEmptyMVar <*> connect defaultConnectInfo + +bootWorkers :: YesodWorker master => Configurator (HandlerT master IO) -> HandlerT master IO () +bootWorkers declareJobs = void $ do + Workers{..} <- workers <$> getYesod + + -- TODO: need to ensure we have enough connections in the pool to cover + -- - concurrency many workers + -- - the heartbeat process + -- - the signal listener + -- - however many connections the client might need + conn <- liftIO $ connect (defaultConnectInfo { connectMaxConnections = 100 }) + conf <- mkConf conn $ do + concurrency 10 + middleware record + middleware retry + declareJobs + + forkHandler handleError $ do + manager <- startProcess conf + liftIO $ do + putMVar wManager manager + forever $ sleep 60 + +handleError :: e -> HandlerT site IO () +handleError _ = $(logError) "handleError" diff --git a/src/Yesod/Worker/Site.hs b/src/Yesod/Worker/Site.hs new file mode 100644 --- /dev/null +++ b/src/Yesod/Worker/Site.hs @@ -0,0 +1,41 @@ +{-# LANGUAGE OverloadedStrings #-} +{-# LANGUAGE QuasiQuotes #-} +{-# LANGUAGE Rank2Types #-} +{-# LANGUAGE RecordWildCards #-} +{-# LANGUAGE TemplateHaskell #-} +{-# LANGUAGE TypeFamilies #-} +module Yesod.Worker.Site where + +import Control.Concurrent +import qualified Data.ByteString.Char8 as BSC +import Data.Maybe (fromMaybe) +import qualified Data.Map as Map +import Database.Redis +import Keenser +import Text.Blaze (ToMarkup(..)) +import Yesod +import Yesod.Worker.Types +import Yesod.Worker.Util + +instance ToMarkup BSC.ByteString where + toMarkup = toMarkup . BSC.unpack + +type WorkerH a = forall master . YesodWorker master => HandlerT Workers (HandlerT master IO) a + +mkYesodSubData "Workers" [parseRoutes| +/ HomeR GET +|] + +getHomeR :: WorkerH Html +getHomeR = do + Workers{..} <- getYesod + mm <- liftIO $ tryReadMVar wManager + case mm of + Just m -> do + ManagerStatus{..} <- checkStatus m wRedis + let info = Map.fromList sState + get key = fromMaybe "" $ Map.lookup key info + lift $ defaultLayout $(whamletFile "templates/home.hamlet") + _ -> do + $(logError) "No manager running" + return "No manager running" diff --git a/src/Yesod/Worker/Types.hs b/src/Yesod/Worker/Types.hs new file mode 100644 --- /dev/null +++ b/src/Yesod/Worker/Types.hs @@ -0,0 +1,14 @@ +module Yesod.Worker.Types where + +import Control.Concurrent (MVar) +import Database.Redis (Connection) +import Keenser (Manager) +import Yesod (Yesod) + +data Workers = Workers + { wManager :: MVar Manager + , wRedis :: Connection + } + +class Yesod master => YesodWorker master where + workers :: master -> Workers diff --git a/src/Yesod/Worker/Util.hs b/src/Yesod/Worker/Util.hs new file mode 100644 --- /dev/null +++ b/src/Yesod/Worker/Util.hs @@ -0,0 +1,35 @@ +{-# LANGUAGE RecordWildCards #-} +module Yesod.Worker.Util + ( enqueue + , enqueueAt + , enqueueIn + ) where + +import qualified Keenser as K +import Yesod +import Yesod.Worker.Types + +import Control.Concurrent (readMVar) +import Data.Thyme.Clock (UTCTime) + +enqueue :: (ToJSON a, YesodWorker master) => K.Worker (HandlerT master IO) a -> a -> HandlerT master IO () +enqueue job args = do + manager <- getManager + K.enqueue manager job args + +enqueueAt :: (ToJSON a, YesodWorker master) => UTCTime -> K.Worker (HandlerT master IO) a -> a -> HandlerT master IO () +enqueueAt time job args = do + manager <- getManager + K.enqueueAt time manager job args + +enqueueIn :: (ToJSON a, YesodWorker master) => Rational -> K.Worker (HandlerT master IO) a -> a -> HandlerT master IO () +enqueueIn snds job args = do + manager <- getManager + K.enqueueIn snds manager job args + +getManager :: YesodWorker master => HandlerT master IO K.Manager +getManager = do + Workers{..} <- workers <$> getYesod + liftIO $ do + m <- readMVar wManager + return $! m diff --git a/test/Spec.hs b/test/Spec.hs new file mode 100644 --- /dev/null +++ b/test/Spec.hs @@ -0,0 +1,2 @@ +main :: IO () +main = putStrLn "Test suite not yet implemented" diff --git a/yesod-worker.cabal b/yesod-worker.cabal --- a/yesod-worker.cabal +++ b/yesod-worker.cabal @@ -1,61 +1,51 @@ --- Initial yesod-worker.cabal generated by cabal init. For further --- documentation, see http://haskell.org/cabal/users-guide/ - name: yesod-worker -version: 0.0.1 -synopsis: Drop-in(ish) background worker system for Yesod apps --- description: -homepage: https://github.com/jamesdabbs/yesod-worker -license: GPL-3 +version: 0.1.0.0 +synopsis: Initial project template from stack +description: Please see README.md +homepage: https://github.com/jamesdabbs/yesod-worker#readme +license: BSD3 license-file: LICENSE author: James Dabbs maintainer: jamesdabbs@gmail.com --- copyright: --- category: +copyright: 2016 +category: Web build-type: Simple -extra-source-files: README.md +-- extra-source-files: cabal-version: >=1.10 - library - exposed-modules: Yesod.Worker - - other-modules: Yesod.Worker.Queue - Yesod.Worker.Types - - ghc-options: -Wall -O2 - - -- These should be the default extensions enabled by Yesod - default-extensions: TemplateHaskell - QuasiQuotes - OverloadedStrings - NoImplicitPrelude - CPP - MultiParamTypeClasses - TypeFamilies - GADTs - GeneralizedNewtypeDeriving - FlexibleContexts - EmptyDataDecls - NoMonomorphismRestriction - DeriveDataTypeable - - -- These constraints should work, but could likely be loosened - build-depends: base >= 4.7 && < 4.8 - , resourcet >= 1.1.2.2 - , persistent >= 2.1 - , yesod >= 1.4 - , stm >= 2.4.2 - , containers >= 0.5 - , transformers-base >= 0.4.2 - , transformers >= 0.4 - , monad-logger >= 0.3 - , monad-control >= 0.3 - , template-haskell - , fast-logger >= 2.2 - , yesod-core >= 1.4 + hs-source-dirs: src + other-modules: Yesod.Worker.Site + Yesod.Worker.Types + Yesod.Worker.Util + exposed-modules: Yesod.Worker + build-depends: base >= 4.7 && < 5 + , blaze-markup + , bytestring + , containers + , hedis + , keenser + , thyme + , yesod + default-language: Haskell2010 - -- Directories containing source files. - -- hs-source-dirs: +-- executable yesod-worker-exe +-- hs-source-dirs: app +-- main-is: Main.hs +-- ghc-options: -threaded -rtsopts -with-rtsopts=-N +-- build-depends: base +-- , yesod-worker +-- default-language: Haskell2010 +test-suite yesod-worker-test + type: exitcode-stdio-1.0 + hs-source-dirs: test + main-is: Spec.hs + build-depends: base + , yesod-worker + ghc-options: -threaded -rtsopts -with-rtsopts=-N default-language: Haskell2010 + +source-repository head + type: git + location: https://github.com/jamesdabbs/yesod-worker