haskell-bee (empty) → 0.1.0.0

raw patch · 8 files changed

+1700/−0 lines, 8 filesdep +aesondep +basedep +haskell-bee

Dependencies added: aeson, base, haskell-bee, safe-exceptions, stm, tasty, tasty-quickcheck, text, unbounded-delays

Files

LICENSE +661/−0
README.md +21/−0
haskell-bee.cabal +133/−0
src/Async/Worker.hs +329/−0
src/Async/Worker/Broker.hs +15/−0
src/Async/Worker/Broker/Types.hs +177/−0
src/Async/Worker/Types.hs +292/−0
tests/unit-tests.hs +72/−0

+ LICENSE view

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+ README.md view

@@ -0,0 +1,21 @@+# Haskell-bee++A lightweight, type-safe library for implementing asynchronous job workers in Haskell.++**Key features:**+- Multiple broker backends (PostgreSQL/PGMQ, Redis, STM)+- Configurable timeout and retry strategies+- Exception-safe job processing+- Support for delayed/periodic tasks++This package contains the core broker and worker implementation of the+[haskell-bee](https://github.com/garganscript/haskell-bee) project+(simple rewrite of Celery in Haskell).++## Documentation++For complete documentation, examples, and setup instructions, see the [main project README](https://github.com/garganscript/haskell-bee/blob/master/README.md).++## Getting Started++The quickest way to get started is to check out the [demo application](https://github.com/garganscript/haskell-bee/tree/master/demo) which shows practical examples of job processing.

+ haskell-bee.cabal view

@@ -0,0 +1,133 @@+cabal-version:      3.4+-- The cabal-version field refers to the version of the .cabal specification,+-- and can be different from the cabal-install (the tool) version and the+-- Cabal (the library) version you are using. As such, the Cabal (the library)+-- version used must be equal or greater than the version stated in this field.+-- Starting from the specification version 2.2, the cabal-version field must be+-- the first thing in the cabal file.++-- Initial package description 'haskell-bee' generated by+-- 'cabal init'. For further documentation, see:+--   http://haskell.org/cabal/users-guide/+--+-- The name of the package.+name:               haskell-bee++-- The package version.+-- See the Haskell package versioning policy (PVP) for standards+-- guiding when and how versions should be incremented.+-- https://pvp.haskell.org+-- PVP summary:     +-+------- breaking API changes+--                  | | +----- non-breaking API additions+--                  | | | +--- code changes with no API change+version:            0.1.0.0++-- A short (one-line) description of the package.+synopsis: A lightweight library for asynchronous job workers with multiple broker backends+          +-- Extra doc files to be distributed with the package, such as a CHANGELOG or a README.+extra-doc-files:    README.md++-- A longer description of the package.+description:        +    Please see the README on GitHub at <https://github.com/garganscript/haskell-bee/blob/master/haskell-bee/README.md>+   +-- URL for the project homepage or repository.+homepage:           https://gitlab.iscpif.fr/gargantext/haskell-bee++-- The license under which the package is released.+license:            AGPL-3.0-or-later++-- The file containing the license text.+license-file:       LICENSE++-- The package author(s).+author:             Gargantext++-- An email address to which users can send suggestions, bug reports, and patches.+maintainer:         gargantext@iscpif.fr++-- A copyright notice.+-- copyright:+category:           Concurrency+build-type:         Simple++-- Extra doc files to be distributed with the package, such as a CHANGELOG or a README.+-- extra-doc-files:    CHANGELOG.md+--                   , README.md++-- Extra source files to be distributed with the package, such as examples, or a tutorial module.+-- extra-source-files:++common warnings+    ghc-options: -Wall++library+    -- Import common warning flags.+    import:           warnings++    -- Modules exported by the library.+    exposed-modules:  Async.Worker+                    , Async.Worker.Broker+                    , Async.Worker.Broker.Types+                    , Async.Worker.Types++    -- Modules included in this library but not exported.+    -- other-modules:++    -- LANGUAGE extensions used by modules in this package.+    -- other-extensions:++    -- Other library packages from which modules are imported.+    build-depends:    base >=4.17.2.0 && < 5+                    , aeson >= 2.1 && < 2.3+                    , safe-exceptions >= 0.1.7 && < 0.2+                    , stm >= 2.5.3 && < 3+                    , text >= 1.2 && < 2.2+                    , unbounded-delays >= 0.1.1 && < 0.2++    -- Directories containing source files.+    hs-source-dirs:   src++    -- Base language which the package is written in.+    default-language: Haskell2010++    default-extensions:+      DuplicateRecordFields+      GeneralizedNewtypeDeriving+      ImportQualifiedPost+      NamedFieldPuns+      NumericUnderscores+      OverloadedStrings+      RecordWildCards++test-suite test-unit+    -- Import common warning flags.+    import:           warnings+    +    type:             exitcode-stdio-1.0+    +    build-depends:    base >=4.17.2.0 && < 5+                    , aeson >= 2.1 && < 2.3+                    , tasty >= 1.5 && < 1.6+                    , tasty-quickcheck >= 0.10 && < 0.12+                    +                    , haskell-bee++    -- Directories containing source files.+    hs-source-dirs:   tests+    main-is: unit-tests.hs++    -- Base language which the package is written in.+    default-language: Haskell2010++    default-extensions:+      DuplicateRecordFields+      GeneralizedNewtypeDeriving+      ImportQualifiedPost+      NamedFieldPuns+      OverloadedStrings+      RecordWildCards++    ghc-options: -threaded+

+ src/Async/Worker.hs view

@@ -0,0 +1,329 @@+{-|+Module      : Async.Worker+Description : Abstract async worker implementation using the 'Queue' typeclass+Copyright   : (c) Gargantext, 2024-Present+License     : AGPL+Maintainer  : gargantext@iscpif.fr+Stability   : experimental+Portability : POSIX++Asynchronous worker.++-}++{-# LANGUAGE FlexibleContexts #-}+{-# LANGUAGE RankNTypes #-}+{-# LANGUAGE ScopedTypeVariables #-}+++module Async.Worker+  ( KillWorkerSafely(..)+  -- * Running+  , run+  , runSingle+  , runSingle'+    -- * Sending jobs+  , sendJob+  -- ** 'SendJob' wrappers+  -- $sendJob+  , mkDefaultSendJob+  , mkDefaultSendJob'+  , sendJob'+  , SendJob(..) )+where+++{- | 'Broker' class type for the underlying broker+-}+import Async.Worker.Broker+{- | Various worker types, in particular 'State'+-}+import Async.Worker.Types+import Control.Concurrent.STM (atomically)+import Control.Concurrent.STM.TVar (readTVarIO, newTVarIO, writeTVar)+import Control.Concurrent.Timeout qualified as Timeout+import Control.Exception.Safe (catches, Handler(..), throwIO, SomeException, Exception)+import Control.Monad (forever, void, when)+++-- | If you want to stop a worker safely, use `throwTo'+-- 'workerThreadId' 'KillWorkerSafely'. This way the worker will stop+-- whatever is doing now and resend the message back to the+-- broker. This way you won't lose your jobs. If you don't care about+-- resuming a job, just set 'resendWhenWorkerKilled' property to+-- 'False'.+data KillWorkerSafely = KillWorkerSafely+  deriving (Show)+instance Exception KillWorkerSafely+++-- | This is the main function to start a worker. It's an infinite+-- loop of reading the next broker message, processing it and handling+-- any errors, issues that might arrise in the meantime.+run :: (HasWorkerBroker b a) => State b a -> IO ()+run state@(State { .. }) = do+  createQueue broker queueName+  forever $ runSingle state++-- | Fetch a single job and run it (create queue first)+runSingle :: (HasWorkerBroker b a) => State b a -> IO ()+runSingle state@(State { .. }) = do+  createQueue broker queueName+  runSingle' state++-- | Fetch a single job and run it. Assumes the queue already exists+runSingle' :: (HasWorkerBroker b a) => State b a -> IO ()+runSingle' state@(State { .. }) = do+      -- TVar to hold currently processed job. This is used for+      -- exception handling.+      mBrokerMessageTVar <- newTVarIO Nothing -- :: IO (TVar (Maybe (BrokerMessage b (Job a))))+      +      catches (do+                brokerMessage <- readMessageWaiting broker queueName+                atomically $ writeTVar mBrokerMessageTVar (Just brokerMessage)+                handleMessage state brokerMessage+                callWorkerJobEvent onJobFinish state brokerMessage+            ) [+        Handler $ \(_err :: KillWorkerSafely) -> do+          mBrokerMessage <- readTVarIO mBrokerMessageTVar+          case mBrokerMessage of+            Just brokerMessage -> do+              let job = toA $ getMessage brokerMessage+              let mdata = metadata job+              -- Should we resend this message?+              when (resendWhenWorkerKilled mdata) $ do+                -- putStrLn $ formatStr state $ "resending job: " <> show job+                +                -- NOTE: Delete first, then create job. It's a bit+                -- safer (same job won't be picked up twice, though we+                -- should be safe anyways, with the timeout)+                void $ deleteMessage broker queueName $ messageId brokerMessage+                void $ sendJob broker queueName (job { metadata = mdata { readCount = readCount mdata + 1 } })+                -- size <- getQueueSize broker queueName+                -- putStrLn $ formatStr state $ "queue size: " <> show size+                +              -- In any case, deinit the broker (i.e. close connection)+              -- deinitBroker broker+            Nothing -> pure ()+            +          -- callback+          callWorkerMJobEvent onWorkerKilledSafely state mBrokerMessage+          +          -- kill worker+          throwIO KillWorkerSafely+        , Handler $ \(err :: JobTimeout b a) -> handleTimeoutError state err+        , Handler $ \err -> do+            mBrokerMessage <- readTVarIO mBrokerMessageTVar+            case mBrokerMessage of+              Just brokerMessage -> do+                callWorkerJobErrorEvent onJobError state brokerMessage err+                handleJobError state brokerMessage+              Nothing -> handleUnknownError state err+        ]+ +handleMessage :: (HasWorkerBroker b a) => State b a -> BrokerMessage b (Job a) -> IO ()+handleMessage state@(State { .. }) brokerMessage = do+  callWorkerJobEvent onMessageReceived state brokerMessage+  let msgId = messageId brokerMessage+  let msg = getMessage brokerMessage+  let job' = toA msg+  -- putStrLn $ formatStr state $ "received job: " <> show (job job')+  let mdata = metadata job'+  let timeoutS = jobTimeout job'+  -- Inform the broker how long a task could take. This way we prevent+  -- the broker from sending this task to another worker (e.g. 'vt' in+  -- PGMQ).+  setMessageTimeout broker queueName msgId (TimeoutS timeoutS)+  -- mTimeout <- Timeout.timeout timeoutS (wrapPerformActionInJobException state brokerMessage)+  mTimeout <- Timeout.timeout ((fromIntegral timeoutS) * microsecond) (runAction state brokerMessage)++  let archiveHandler = do+        case archiveStrategy mdata of+          ASDelete -> do+            -- putStrLn $ formatStr state $ "deleting completed job " <> show msgId <> " (strategy: " <> show archiveStrategy <> ")"+            deleteMessage broker queueName msgId+          ASArchive -> do+            -- putStrLn $ formatStr state $ "archiving completed job " <> show msgId <> " (strategy: " <> show archiveStrategy <> ")"+            archiveMessage broker queueName msgId+  +  case mTimeout of+    Just _ -> archiveHandler+    Nothing -> do+      callWorkerJobEvent onJobTimeout state brokerMessage+      throwIO $ JobTimeout { jtBMessage = brokerMessage+                           , jtTimeout = timeoutS }+  -- onMessageFetched broker queue msg+++-- -- | It's important to know if an exception occured inside a job. This+-- -- way we can apply error recovering strategy and adjust this job in+-- -- the broker+-- wrapPerformActionInJobException :: (HasWorkerBroker b a) => State b a -> BrokerMessage b (Job a) -> IO ()+-- wrapPerformActionInJobException state@(State { onJobError }) brokerMessage = do+--   catch (do+--             runAction state brokerMessage+--         )+--     (\(err :: SomeException) -> do+--         callWorkerJobEvent onJobError state brokerMessage+--         throwIO err+--         )+++callWorkerJobEvent :: WorkerJobEvent b a+                   -> State b a+                   -> BrokerMessage b (Job a)+                   -> IO ()+callWorkerJobEvent Nothing _ _ = pure ()+callWorkerJobEvent (Just event) state brokerMessage = event state brokerMessage++callWorkerJobErrorEvent :: WorkerJobErrorEvent b a+                        -> State b a+                        -> BrokerMessage b (Job a)+                        -> SomeException+                        -> IO ()+callWorkerJobErrorEvent Nothing _ _ _ = pure ()+callWorkerJobErrorEvent (Just event) state brokerMessage err = event state brokerMessage err++callWorkerMJobEvent :: WorkerMJobEvent b a+                    -> State b a+                    -> Maybe (BrokerMessage b (Job a))+                    -> IO ()+callWorkerMJobEvent Nothing _ _ = pure ()+callWorkerMJobEvent (Just event) state mBrokerMessage = event state mBrokerMessage++handleTimeoutError :: (HasWorkerBroker b a) => State b a -> JobTimeout b a -> IO ()+handleTimeoutError _state@(State { .. }) _jt@(JobTimeout { .. }) = do+  -- putStrLn $ formatStr state $ show jt+  let msgId = messageId jtBMessage+  let job = toA $ getMessage jtBMessage+  -- putStrLn $ formatStr state $ "timeout for job: " <> show job+  let mdata = metadata job+  case timeoutStrategy mdata of+    TSDelete -> deleteMessage broker queueName msgId+    TSArchive -> archiveMessage broker queueName msgId+    TSRepeat -> do+      void $ deleteMessage broker queueName msgId+      void $ sendJob broker queueName (job { metadata = mdata { readCount = readCount mdata + 1 } })+    TSRepeatNElseArchive n -> do+      let readCt = readCount mdata+      -- OK so this can be repeated at most 'n' times, compare 'readCt' with 'n'+      if readCt >= n then+        archiveMessage broker queueName msgId+      else do+        -- NOTE In rare cases, when worker hangs, we might lose a job+        -- here? (i.e. delete, then resend)+        -- Also, be aware that messsage id will change with resend++        -- Delete this job first, otherwise we'll be duplicating jobs.+        deleteMessage broker queueName msgId++        -- Send this job again, with increased 'readCount'+        void $ sendJob broker queueName (job { metadata = mdata { readCount = readCt + 1 } })+    TSRepeatNElseDelete n -> do+      let readCt = readCount mdata+      -- OK so this can be repeated at most 'n' times, compare 'readCt' with 'n'+      if readCt >= n then+        deleteMessage broker queueName msgId+      else do+        -- NOTE In rare cases, when worker hangs, we might lose a job+        -- here? (i.e. delete, then resend)+        -- Also, be aware that messsage id will change with resend++        -- Delete this job first, otherwise we'll be duplicating jobs.+        deleteMessage broker queueName msgId++        -- Send this job again, with increased 'readCount'+        void $ sendJob broker queueName (job { metadata = mdata { readCount = readCt + 1 } })++handleJobError :: (HasWorkerBroker b a) => State b a -> BrokerMessage b (Job a) -> IO ()+handleJobError _state@(State { .. }) brokerMessage = do+  let msgId = messageId brokerMessage+  let job = toA $ getMessage brokerMessage+  -- putStrLn $ formatStr state $ "error: " <> show je <> " for job " <> show job+  let mdata = metadata job+  case errorStrategy mdata of+    ESDelete -> deleteMessage broker queueName msgId+    ESArchive -> archiveMessage broker queueName msgId+    ESRepeatNElseArchive n -> do+      let readCt = readCount mdata+      if readCt >= n then+        archiveMessage broker queueName msgId+      else do+        -- Delete this job first, otherwise we'll be duplicating jobs.+        deleteMessage broker queueName msgId++        void $ sendJob broker queueName (job { metadata = mdata { readCount = readCt + 1 } })++handleUnknownError :: State b a -> SomeException -> IO ()+handleUnknownError state err = putStrLn $ formatStr state $ "unknown error: " <> show err++sendJob :: (HasWorkerBroker b a) => Broker b (Job a) -> Queue -> Job a -> IO (MessageId b)+sendJob broker queueName job =+  sendJobDelayed broker queueName job 0++sendJobDelayed :: (HasWorkerBroker b a) => Broker b (Job a) -> Queue -> Job a -> TimeoutS -> IO (MessageId b)+sendJobDelayed broker queueName job timeoutS = do+  sendMessageDelayed broker queueName (toMessage job) timeoutS++microsecond :: Integer+microsecond = 10^(6 :: Integer)+++{- $sendJob+ A worker job has quite a few metadata. Here are some utilities for+ constructing them more easily.+-}++-- | Wraps parameters for the 'sendJob' function+data SendJob b a =+  SendJob { broker       :: Broker b (Job a)+          , queue        :: Queue+          , msg          :: a+          , delay        :: TimeoutS  -- initial delay for the message+          , archStrat    :: ArchiveStrategy+          , errStrat     :: ErrorStrategy+          , toStrat      :: TimeoutStrategy+          , timeout      :: Timeout+          , resendOnKill :: Bool}++-- | Create a 'SendJob' data with some defaults+mkDefaultSendJob :: Broker b (Job a)+                 -> Queue+                 -> a+                 -> Timeout+                 -> SendJob b a+mkDefaultSendJob broker queue msg timeout =+  SendJob { broker+          , queue+          , msg+          , delay = 0+          -- | remove finished jobs+          , archStrat = ASDelete+          -- | archive errored jobs (for inspection later)+          , errStrat = ESArchive+          -- | repeat timed out jobs+          , toStrat = TSRepeat+          , timeout+          , resendOnKill = True }+++-- | Like 'mkDefaultSendJob' but with default timeout+mkDefaultSendJob' :: Broker b (Job a)+                  -> Queue+                  -> a+                  -> SendJob b a+mkDefaultSendJob' b q m = mkDefaultSendJob b q m defaultTimeout+  where+    defaultTimeout = 10++    +-- | Call 'sendJob' with 'SendJob b a' data+sendJob' :: (HasWorkerBroker b a) => SendJob b a -> IO (MessageId b)+sendJob' (SendJob { .. }) = do+  let metadata = defaultMetadata { archiveStrategy = archStrat+                                 , errorStrategy = errStrat+                                 , timeoutStrategy = toStrat+                                 , timeout = timeout+                                 , resendWhenWorkerKilled = resendOnKill }+  let job = Job { job = msg, metadata }+  sendJobDelayed broker queue job delay

+ src/Async/Worker/Broker.hs view

@@ -0,0 +1,15 @@+{-|+Module      : Async.Worker.Broker+Description : Typeclass for the underlying broker that powers the worker+Copyright   : (c) Gargantext, 2024-Present+License     : AGPL+Maintainer  : gargantext@iscpif.fr+Stability   : experimental+Portability : POSIX+-}++module Async.Worker.Broker+  ( module Async.Worker.Broker.Types )+where++import Async.Worker.Broker.Types

+ src/Async/Worker/Broker/Types.hs view

@@ -0,0 +1,177 @@+{-|+Module      : Async.Worker.Broker.Types+Description : Typeclass for the underlying broker that powers the worker+Copyright   : (c) Gargantext, 2024-Present+License     : AGPL+Maintainer  : gargantext@iscpif.fr+Stability   : experimental+Portability : POSIX++Broker typeclass definition.+-}+++{-# LANGUAGE ConstraintKinds       #-}+{-# LANGUAGE DerivingStrategies    #-}+{-# LANGUAGE FlexibleContexts      #-}+{-# LANGUAGE MultiParamTypeClasses #-}+{-# LANGUAGE ScopedTypeVariables   #-}+{-# LANGUAGE TypeFamilies          #-}+{-# LANGUAGE UndecidableInstances  #-}+    +module Async.Worker.Broker.Types+  ( Queue(..)+  , renderQueue+  , TimeoutS(..)+  -- * Main broker typeclass+  -- $broker+  , MessageBroker(..)+  , SerializableMessage+  )+where++import Data.Aeson (FromJSON, ToJSON)+import Data.Kind (Type)+import Data.String (IsString)+import Data.Text qualified as T+import Data.Typeable (Typeable)+++newtype Queue = Queue { _Queue :: T.Text }+  deriving stock (Eq, Ord)+  deriving newtype (Semigroup, IsString, Show)++-- | This is just a wrapper so that you know you use seconds as units+-- for `Int`.+newtype TimeoutS = TimeoutS { _TimeoutS :: Int  } -- timeout for a message, in seconds+  deriving stock (Eq, Ord)+  deriving newtype (Num, Show)++renderQueue :: Queue -> String+renderQueue = T.unpack . _Queue++{- $broker+/NOTE/ There are 3 types of messages here:++ * 'a' the underlying, user-defined message+ * 'Async.Worker.Types.Job' 'a' worker definition, containing message metadata+ * 'BrokerMessage' 'message' 'm', i.e. for 'PGMQ', it returns things+   like: 'Database.Broker.PGMQ.Simple.msgId',+   'Database.Broker.PGMQ.Simple.readCt',+   'Database.Broker.PGMQ.Simple.enqueuedAt',+   'Database.Broker.PGMQ.Simple.vt'++Also:++ * 'a' is read-write+ * 'Async.Worker.Types.Job' 'a' is read-write+ * 'BrokerMessage' is read-only, i.e. we can't save it to broker and+   it doesn't make sense to construct it on Haskell side. Instead, we+   save 'Job' 'a' and get 'BrokerMessage' when reading. In this sense,+   read and send are not symmetrical (similarly, Opaleye has Read and+   Write tables).+-}++-- | We want to assert some way to serialize a message. JSON is+-- assumed here. This isn't strictly broker-related but nevertheless+-- is useful.+type SerializableMessage a = ( FromJSON a+                             , ToJSON a+                             -- NOTE This shouldn't be necessary+                             , Typeable a )+           +{-|+  This is an interface for basic broker functionality.+-}+class (+        Eq (MessageId b)+      , Show (MessageId b)+      , Ord (MessageId b)+      , ToJSON (MessageId b)+      , FromJSON (MessageId b)+      , Show (BrokerMessage b a)+      ) => MessageBroker b a where+  -- | Data representing the broker+  data family Broker b a :: Type+  -- | Data represenging message that is returned by broker. You're+  -- not supposed to construct this type yourself (in similar spirit,+  -- Opaleye uses 'selectTable'+  -- https://hackage.haskell.org/package/opaleye-0.10.3.1/docs/Opaleye-Table.html#v:selectTable)+  data family BrokerMessage b a :: Type+  -- | Data that we serialize into broker (worker will wrap this into+  -- 'Async.Worker.Types.Job' 'a')+  data family Message b a :: Type+  -- | The message id type (needed for delete/archive operations)+  data family MessageId b :: Type++  -- | All the parameters needed for broker intialization+  data family BrokerInitParams b a :: Type++  -- The following are just constructors and deconstructors for the+  -- 'BrokerMessage', 'Message' data types+  +  -- | Operation for getting the 'MessageId' from 'BrokerMessage'+  messageId :: BrokerMessage b a -> MessageId b+  +  -- | 'BrokerMessage' contains 'Message' inside, this is a+  -- deconstructor for 'BrokerMessage'+  getMessage :: BrokerMessage b a -> Message b a++  -- | Convert 'a' to 'Message' 'b' 'a'+  toMessage :: a -> Message b a+  -- | Convert 'Message' 'b' 'a' to 'a'+  toA :: Message b a -> a++  +  -- | Initialize broker with given 'BrokerInitParams'.+  initBroker :: BrokerInitParams b a -> IO (Broker b a)+  -- | Deconstruct broker (e.g. close DB connection)+  deinitBroker :: Broker b a -> IO ()++  +  {-| Create new queue with given name. Optionally any other+    initializations can be added here. -}+  createQueue :: Broker b a -> Queue -> IO ()++  {-| Drop queue -}+  dropQueue :: Broker b a -> Queue -> IO ()++  {-| Read message from queue, waiting for it if not present (NOTE: for+  pgmq, this leaves the message in queue, you need to use+  'setMessageTimeout' to prevent other workers from seeing this+  message). -}+  readMessageWaiting :: Broker b a -> Queue -> IO (BrokerMessage b a)++  {-| Pop message from queue, waiting for it if not present -}+  popMessageWaiting :: Broker b a -> Queue -> IO (BrokerMessage b a)++  {-| We sometimes need a way to tell the broker that a message shouldn't+  be visible for given amount of time (e.g. 'visibility timeout'+  setting in PGMQ). The broker operates only on 'a' level and isn't+  aware of 'Job' with its 'JobMetadata'. Hence, it's the worker's+  responsibility to properly set timeout after message is read. -}+  setMessageTimeout :: Broker b a -> Queue -> MessageId b -> TimeoutS -> IO ()++  {-| Send message -}+  sendMessage :: Broker b a -> Queue -> Message b a -> IO (MessageId b)++  {-| Send message with initial delay -}+  sendMessageDelayed :: Broker b a -> Queue -> Message b a -> TimeoutS -> IO (MessageId b)++  {-| Delete message -}+  deleteMessage :: Broker b a -> Queue -> MessageId b -> IO ()++  {-| Archive message -}+  archiveMessage :: Broker b a -> Queue -> MessageId b -> IO ()++  {-| Queue size -}+  getQueueSize :: Broker b a -> Queue -> IO Int++  {-| Read archived message -}+  getArchivedMessage :: Broker b a -> Queue -> MessageId b -> IO (Maybe (BrokerMessage b a))++  {-| List all pending message ids -}+  listPendingMessageIds :: Broker b a -> Queue -> IO [MessageId b]++  {-| Get message by it's id -}+  getMessageById :: Broker b a -> Queue -> MessageId b -> IO (Maybe (BrokerMessage b a))

+ src/Async/Worker/Types.hs view

@@ -0,0 +1,292 @@+{-|+Module      : Async.Worker.Types+Description : Types for the async worker+Copyright   : (c) Gargantext, 2024-Present+License     : AGPL+Maintainer  : gargantext@iscpif.fr+Stability   : experimental+Portability : POSIX++Types for worker.+-}++{-# LANGUAGE ConstraintKinds #-}+{-# LANGUAGE FlexibleContexts #-}+{-# LANGUAGE RankNTypes #-}+{-# LANGUAGE StandaloneDeriving #-}+{-# LANGUAGE UndecidableInstances #-}+    +module Async.Worker.Types+  (+    -- * Main worker state+    State(..)+  -- * Job wrapped in metadata+  , Job(..)+    -- ** Job metadata+  , JobMetadata(..)+  , defaultMetadata+    -- *** Strategies for handling finished, errored, timed-out jobs+  , ArchiveStrategy(..)+  , ErrorStrategy(..)+  , TimeoutStrategy(..)+  -- ** Job utility functions+  , getJob+  , jobTimeout+  , Timeout+  , runAction+  -- ** Actions that the worker will perform+  , PerformAction+  -- * Events emitted during job lifetime+  , WorkerJobEvent+  , WorkerJobErrorEvent+  , WorkerMJobEvent+  -- * Other useful types and functions+  , HasWorkerBroker+  , formatStr+  , JobTimeout(..) )+where++import Async.Worker.Broker.Types (Broker, BrokerMessage, MessageBroker, Queue)+import Control.Applicative ((<|>))+import Control.Exception.Safe (Exception, SomeException)+import Data.Aeson (FromJSON(..), ToJSON(..), object, (.=), (.:), withObject, withText)+import Data.Text qualified as T+import Data.Typeable (Typeable)+++type ReadCount = Int+type Timeout = Int++    ++-- | Strategy for archiving finished jobs+data ArchiveStrategy =+    -- | Delete message when it's done+    ASDelete+    -- | Archive message when it's done+  | ASArchive+  deriving (Eq, Show)+instance ToJSON ArchiveStrategy where+  toJSON ASDelete = toJSON ("ASDelete" :: String)+  toJSON ASArchive = toJSON ("ASArchive" :: String)+instance FromJSON ArchiveStrategy where+  parseJSON = withText "ArchiveStrategy" $ \s -> do+    case s of+      "ASDelete" -> pure ASDelete+      "ASArchive" -> pure ASArchive+      s' -> fail $ T.unpack s'+  +-- | Strategy for handling jobs with errors+data ErrorStrategy =+    -- | Delete job when it threw an error+    ESDelete+    -- | Archive job when it threw an error+  | ESArchive+    -- | Try to repeat the job when an error ocurred (at most N+    -- times), otherwise archive the job.+  | ESRepeatNElseArchive Int+  -- TODO Repeat N times+  deriving (Eq, Show)+instance ToJSON ErrorStrategy where+  toJSON ESDelete = toJSON ("ESDelete" :: String)+  toJSON ESArchive = toJSON ("ESArchive" :: String)+  toJSON (ESRepeatNElseArchive n) = toJSON $ object [ "ESRepeatNElseArchive" .= n ]+instance FromJSON ErrorStrategy where+  parseJSON v = parseText v <|> parseESRepeatN v+    where+      parseText = withText "ErrorStrategy" $ \s -> do+        case s of+          "ESDelete" -> pure ESDelete+          "ESArchive" -> pure ESArchive+          s' -> fail $ T.unpack s'+      parseESRepeatN = withObject "ESRepeatN" $ \o -> do+        n <- o .: "ESRepeatNElseArchive"+        pure $ ESRepeatNElseArchive n++-- | Strategy for handling job timeouts+data TimeoutStrategy =+    -- | Delete job when it timed out+    TSDelete+    -- | Archive job when it timed out+  | TSArchive+    -- | Repeat job when it timed out (infinitely)+  | TSRepeat+    -- | Repeat job when it timed out (at most N times), otherwise archive it+  | TSRepeatNElseArchive Int+    -- | Repeat job when it timed out (at most N times), otherwise delete it+  | TSRepeatNElseDelete Int+  deriving (Eq, Show)+instance ToJSON TimeoutStrategy where+  toJSON TSDelete = toJSON ("TSDelete" :: String)+  toJSON TSArchive = toJSON ("TSArchive" :: String)+  toJSON TSRepeat = toJSON ("TSRepeat" :: String)+  toJSON (TSRepeatNElseArchive n) = toJSON $ object [ "TSRepeatNElseArchive" .= n ]+  toJSON (TSRepeatNElseDelete n) = toJSON $ object [ "TSRepeatNElseDelete" .= n ]+instance FromJSON TimeoutStrategy where+  parseJSON v = parseText v+            <|> parseTSRepeatNElseArchive v+            <|> parseTSRepeatNElseDelete v+    where+      -- | Parser for textual formats+      parseText = withText "TimeoutStrategy (text)" $ \s -> do+        case s of+          "TSDelete" -> pure TSDelete+          "TSArchive" -> pure TSArchive+          "TSRepeat" -> pure TSRepeat+          s' -> fail $ T.unpack s'+      -- | Parser for 'TSRepeatN' object+      parseTSRepeatNElseArchive = withObject "TimeoutStrategy (TSRepeatNElseArchive)" $ \o -> do+        n <- o .: "TSRepeatNElseArchive"+        pure $ TSRepeatNElseArchive n+      parseTSRepeatNElseDelete = withObject "TimeoutStrategy (TSRepeatNElseDelete)" $ \o -> do+        n <- o .: "TSRepeatNElseDelete"+        pure $ TSRepeatNElseDelete n++    +-- | Metadata associated with a job.+data JobMetadata =+  JobMetadata {+                -- | What to do after job is finished successfully+                archiveStrategy  :: ArchiveStrategy+                -- | What to do when a job ends with error+              , errorStrategy    :: ErrorStrategy+                -- | What to do when a job ends with timeout+              , timeoutStrategy  :: TimeoutStrategy+              -- | Time after which the job is considered to time-out+              -- (in seconds).+              , timeout          :: Timeout+              -- | Read count so we know how many times this message+              -- was processed+              , readCount        :: ReadCount+              -- | A worker might have processed a task and be+              -- killed. If 'resendWhenWorkerKilled' is 'True', this+              -- job will be resent to broker and picked up+              -- later. Otherwise it will be discarded.+              , resendWhenWorkerKilled :: Bool }+  deriving (Eq, Show)+instance ToJSON JobMetadata where+  toJSON (JobMetadata { .. }) =+    toJSON $ object [+          "astrat" .= archiveStrategy+        , "estrat" .= errorStrategy+        , "tstrat" .= timeoutStrategy+        , "timeout" .= timeout+        , "readCount" .= readCount+        , "resendWhenWorkerKilled" .= resendWhenWorkerKilled+        ]+instance FromJSON JobMetadata where+  parseJSON = withObject "JobMetadata" $ \o -> do+    archiveStrategy <- o .: "astrat"+    errorStrategy <- o .: "estrat"+    timeoutStrategy <- o .: "tstrat"+    timeout <- o .: "timeout"+    readCount <- o .: "readCount"+    resendWhenWorkerKilled <- o .: "resendWhenWorkerKilled"+    return $ JobMetadata { .. }++-- | For a typical 'Job' it's probably sane to just archive it no+-- matter how it finished.+defaultMetadata :: JobMetadata+defaultMetadata =+  JobMetadata { archiveStrategy = ASArchive+              , errorStrategy = ESArchive+              , timeoutStrategy = TSArchive+              , timeout = 10+              , readCount = 0+              , resendWhenWorkerKilled = True }+    +-- | Worker 'Job' is 'a' (defining action to call via 'performAction')+-- together with associated 'JobMetadata'.+data Job a =+  Job { job :: a+      , metadata :: JobMetadata }+  deriving (Eq, Show)++-- | Given worker 'Job' 'a', return the 'a' part+getJob :: Job a -> a+getJob (Job { job }) = job+instance ToJSON a => ToJSON (Job a) where+  toJSON (Job { .. }) =+    toJSON $ object [+          "metadata" .= metadata+        , "job" .= job+        ]+instance FromJSON a => FromJSON (Job a) where+  parseJSON = withObject "Job" $ \o -> do+    metadata <- o .: "metadata"+    job <- o .: "job"+    return $ Job { .. }++-- | For a given 'Job', return it's 'timeout' value from+-- 'JobMetadata'.+jobTimeout :: Job a -> Timeout+jobTimeout (Job { metadata }) = timeout metadata+    ++-- | Main state for a running worker ('b' is 'Broker', 'a' is the+-- underlying message).+--+-- 'a' is the underlying message specification and is+-- implementation-dependent, e.g. can be of JSON form+--+-- @+-- {"function": ..., "arguments": [...]}+-- @+--+-- 'Job' 'a' is worker's wrapper around that message with metadata+-- (corresponds to broker 'Async.Worker.Broker.Types.Message' 'b'+-- 'a'). 'BrokerMessage' 'b 'a', on the other hand, is what we get+-- when the broker reads that message).+--+-- Note that our underlying 'Broker' handles messages of type 'Job'+-- 'a'.+data State b a =+  State { broker            :: Broker b (Job a)+        -- | Queue associated with this worker. If you want to support+        -- more queues, spawn more workers.+        , queueName         :: Queue+        -- | Name of this worker (useful for debugging).+        , name              :: String+        -- | Actions that will be performed when message 'a' arrives.+        , performAction     :: PerformAction b a+        +        -- | Event emitted after job was received from broker+        , onMessageReceived :: WorkerJobEvent b a+        -- | Event emitted after job was finished successfully+        , onJobFinish       :: WorkerJobEvent b a+        -- | Event emitted after job timed out+        , onJobTimeout      :: WorkerJobEvent b a+        -- | Event emitted after job ended with error+        , onJobError        :: WorkerJobErrorEvent b a+        -- | Event emitted when worker is safely killed (don't overuse it)+        , onWorkerKilledSafely :: WorkerMJobEvent b a }++-- | Helper function to call an action for given worker, for a+-- 'BrokerMessage'.+runAction :: State b a -> BrokerMessage b (Job a) -> IO ()+runAction state brokerMessage = (performAction state) state brokerMessage++type WorkerJobEvent b a = Maybe (State b a -> BrokerMessage b (Job a) -> IO ())+type WorkerJobErrorEvent b a = Maybe (State b a -> BrokerMessage b (Job a) -> SomeException -> IO ())+type WorkerMJobEvent b a = Maybe (State b a -> Maybe (BrokerMessage b (Job a)) -> IO ())++-- | Callback definition (what to execute when a message arrives)+type PerformAction b a =+  State b a -> BrokerMessage b (Job a) -> IO ()+++-- | /TODO/ 'Show' 'a' could be removed. Any logging can be done as+-- part of 'on' events in 'State'.+type HasWorkerBroker b a = ( MessageBroker b (Job a), Typeable a, Typeable b, Show a )++-- | Helper function to format a string with worker name (for logging)+formatStr :: State b a -> String -> String+formatStr (State { name }) msg =+  "[" <> name <> "] " <> msg++-- | An exception, thrown when job times out+data JobTimeout b a =+  JobTimeout { jtBMessage  :: BrokerMessage b (Job a)+             , jtTimeout   :: Timeout }+deriving instance (Show (BrokerMessage b (Job a))) => Show (JobTimeout b a)+instance (Show (BrokerMessage b (Job a)), Typeable a, Typeable b) => Exception (JobTimeout b a)

+ tests/unit-tests.hs view

@@ -0,0 +1,72 @@+{-# OPTIONS_GHC -Wno-orphans -Wno-missing-signatures #-}++module Main where++import Async.Worker.Types qualified as WT+import Data.Aeson qualified as Aeson+import Test.Tasty+import Test.Tasty.QuickCheck as QC+    ++main = defaultMain tests++tests :: TestTree+tests = testGroup "Tests" [propertyTests, unitTests]++++propertyTests = testGroup "Property tests" [aesonPropTests]+    +aesonPropTests = testGroup "Aeson (de-)serialization property tests" $+ [ aesonPropJobMetadataTests+ , aesonPropJobTests ]++instance QC.Arbitrary WT.ArchiveStrategy where+  arbitrary = QC.elements [ WT.ASDelete, WT.ASArchive ]+instance QC.Arbitrary WT.ErrorStrategy where +  arbitrary = do+    n <- arbitrary+    QC.elements [ WT.ESDelete, WT.ESArchive, WT.ESRepeatNElseArchive n ]+instance QC.Arbitrary WT.TimeoutStrategy where +  arbitrary = do+    n <- arbitrary+    m <- arbitrary+    QC.elements [ WT.TSDelete+                , WT.TSArchive+                , WT.TSRepeat+                , WT.TSRepeatNElseArchive n+                , WT.TSRepeatNElseDelete m ]+instance QC.Arbitrary WT.JobMetadata where+  arbitrary = do+    archiveStrategy <- arbitrary+    errorStrategy <- arbitrary+    timeoutStrategy <- arbitrary+    timeout <- arbitrary+    readCount <- arbitrary+    resendWhenWorkerKilled <- arbitrary+    return $ WT.JobMetadata { .. }+   +aesonPropJobMetadataTests = testGroup "Aeson WT.JobMetadata (de-)serialization tests" $+  [ QC.testProperty "Aeson.decode . Aeson.encode == id" $+      \jm ->+        Aeson.decode (Aeson.encode (jm :: WT.JobMetadata)) == Just jm+  ]++instance QC.Arbitrary a => QC.Arbitrary (WT.Job a) where+  arbitrary = WT.Job <$> arbitrary <*> arbitrary+  +aesonPropJobTests = testGroup "Aeson WT.Job (de-)serialization tests" $+  [ QC.testProperty "Aeson.decode . Aeson.encode == id" $+      \j ->+        Aeson.decode (Aeson.encode (j :: WT.Job String)) == Just j+  ]++    +unitTests = testGroup "Unit tests" []+  -- [ testCase "List comparison (different length)" $+  --     [1, 2, 3] `compare` [1,2] @?= GT++  -- -- the following test does not hold+  -- , testCase "List comparison (same length)" $+  --     [1, 2, 3] `compare` [1,2,2] @?= LT+  -- ]