diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,13 @@ +Change log +========== + +async-combinators uses [PVP Versioning][1]. +The change log is available [on GitHub][2]. + +0.0.0 +===== + +* Initially created. + +[1]: https://pvp.haskell.org +[2]: https://github.com/serokell/async-combinators/releases diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,373 @@ +Mozilla Public License Version 2.0 +================================== + +1. Definitions +-------------- + +1.1. "Contributor" + means each individual or legal entity that creates, contributes to + the creation of, or owns Covered Software. + +1.2. "Contributor Version" + means the combination of the Contributions of others (if any) used + by a Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" + means Covered Software of a particular Contributor. + +1.4. "Covered Software" + means Source Code Form to which the initial Contributor has attached + the notice in Exhibit A, the Executable Form of such Source Code + Form, and Modifications of such Source Code Form, in each case + including portions thereof. + +1.5. "Incompatible With Secondary Licenses" + means + + (a) that the initial Contributor has attached the notice described + in Exhibit B to the Covered Software; or + + (b) that the Covered Software was made available under the terms of + version 1.1 or earlier of the License, but not also under the + terms of a Secondary License. + +1.6. "Executable Form" + means any form of the work other than Source Code Form. + +1.7. "Larger Work" + means a work that combines Covered Software with other material, in + a separate file or files, that is not Covered Software. + +1.8. "License" + means this document. + +1.9. "Licensable" + means having the right to grant, to the maximum extent possible, + whether at the time of the initial grant or subsequently, any and + all of the rights conveyed by this License. + +1.10. "Modifications" + means any of the following: + + (a) any file in Source Code Form that results from an addition to, + deletion from, or modification of the contents of Covered + Software; or + + (b) any new file in Source Code Form that contains any Covered + Software. + +1.11. "Patent Claims" of a Contributor + means any patent claim(s), including without limitation, method, + process, and apparatus claims, in any patent Licensable by such + Contributor that would be infringed, but for the grant of the + License, by the making, using, selling, offering for sale, having + made, import, or transfer of either its Contributions or its + Contributor Version. + +1.12. "Secondary License" + means either the GNU General Public License, Version 2.0, the GNU + Lesser General Public License, Version 2.1, the GNU Affero General + Public License, Version 3.0, or any later versions of those + licenses. + +1.13. "Source Code Form" + means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") + means an individual or a legal entity exercising rights under this + License. For legal entities, "You" includes any entity that + controls, is controlled by, or is under common control with You. For + purposes of this definition, "control" means (a) the power, direct + or indirect, to cause the direction or management of such entity, + whether by contract or otherwise, or (b) ownership of more than + fifty percent (50%) of the outstanding shares or beneficial + ownership of such entity. + +2. License Grants and Conditions +-------------------------------- + +2.1. Grants + +Each Contributor hereby grants You a world-wide, royalty-free, +non-exclusive license: + +(a) under intellectual property rights (other than patent or trademark) + Licensable by such Contributor to use, reproduce, make available, + modify, display, perform, distribute, and otherwise exploit its + Contributions, either on an unmodified basis, with Modifications, or + as part of a Larger Work; and + +(b) under Patent Claims of such Contributor to make, use, sell, offer + for sale, have made, import, and otherwise transfer either its + Contributions or its Contributor Version. + +2.2. Effective Date + +The licenses granted in Section 2.1 with respect to any Contribution +become effective for each Contribution on the date the Contributor first +distributes such Contribution. + +2.3. Limitations on Grant Scope + +The licenses granted in this Section 2 are the only rights granted under +this License. No additional rights or licenses will be implied from the +distribution or licensing of Covered Software under this License. +Notwithstanding Section 2.1(b) above, no patent license is granted by a +Contributor: + +(a) for any code that a Contributor has removed from Covered Software; + or + +(b) for infringements caused by: (i) Your and any other third party's + modifications of Covered Software, or (ii) the combination of its + Contributions with other software (except as part of its Contributor + Version); or + +(c) under Patent Claims infringed by Covered Software in the absence of + its Contributions. + +This License does not grant any rights in the trademarks, service marks, +or logos of any Contributor (except as may be necessary to comply with +the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + +No Contributor makes additional grants as a result of Your choice to +distribute the Covered Software under a subsequent version of this +License (see Section 10.2) or under the terms of a Secondary License (if +permitted under the terms of Section 3.3). + +2.5. Representation + +Each Contributor represents that the Contributor believes its +Contributions are its original creation(s) or it has sufficient rights +to grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + +This License is not intended to limit any rights You have under +applicable copyright doctrines of fair use, fair dealing, or other +equivalents. + +2.7. Conditions + +Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted +in Section 2.1. + +3. Responsibilities +------------------- + +3.1. Distribution of Source Form + +All distribution of Covered Software in Source Code Form, including any +Modifications that You create or to which You contribute, must be under +the terms of this License. You must inform recipients that the Source +Code Form of the Covered Software is governed by the terms of this +License, and how they can obtain a copy of this License. You may not +attempt to alter or restrict the recipients' rights in the Source Code +Form. + +3.2. Distribution of Executable Form + +If You distribute Covered Software in Executable Form then: + +(a) such Covered Software must also be made available in Source Code + Form, as described in Section 3.1, and You must inform recipients of + the Executable Form how they can obtain a copy of such Source Code + Form by reasonable means in a timely manner, at a charge no more + than the cost of distribution to the recipient; and + +(b) You may distribute such Executable Form under the terms of this + License, or sublicense it under different terms, provided that the + license for the Executable Form does not attempt to limit or alter + the recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + +You may create and distribute a Larger Work under terms of Your choice, +provided that You also comply with the requirements of this License for +the Covered Software. If the Larger Work is a combination of Covered +Software with a work governed by one or more Secondary Licenses, and the +Covered Software is not Incompatible With Secondary Licenses, this +License permits You to additionally distribute such Covered Software +under the terms of such Secondary License(s), so that the recipient of +the Larger Work may, at their option, further distribute the Covered +Software under the terms of either this License or such Secondary +License(s). + +3.4. Notices + +You may not remove or alter the substance of any license notices +(including copyright notices, patent notices, disclaimers of warranty, +or limitations of liability) contained within the Source Code Form of +the Covered Software, except that You may alter any license notices to +the extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + +You may choose to offer, and to charge a fee for, warranty, support, +indemnity or liability obligations to one or more recipients of Covered +Software. However, You may do so only on Your own behalf, and not on +behalf of any Contributor. You must make it absolutely clear that any +such warranty, support, indemnity, or liability obligation is offered by +You alone, and You hereby agree to indemnify every Contributor for any +liability incurred by such Contributor as a result of warranty, support, +indemnity or liability terms You offer. You may include additional +disclaimers of warranty and limitations of liability specific to any +jurisdiction. + +4. Inability to Comply Due to Statute or Regulation +--------------------------------------------------- + +If it is impossible for You to comply with any of the terms of this +License with respect to some or all of the Covered Software due to +statute, judicial order, or regulation then You must: (a) comply with +the terms of this License to the maximum extent possible; and (b) +describe the limitations and the code they affect. Such description must +be placed in a text file included with all distributions of the Covered +Software under this License. Except to the extent prohibited by statute +or regulation, such description must be sufficiently detailed for a +recipient of ordinary skill to be able to understand it. + +5. Termination +-------------- + +5.1. The rights granted under this License will terminate automatically +if You fail to comply with any of its terms. However, if You become +compliant, then the rights granted under this License from a particular +Contributor are reinstated (a) provisionally, unless and until such +Contributor explicitly and finally terminates Your grants, and (b) on an +ongoing basis, if such Contributor fails to notify You of the +non-compliance by some reasonable means prior to 60 days after You have +come back into compliance. Moreover, Your grants from a particular +Contributor are reinstated on an ongoing basis if such Contributor +notifies You of the non-compliance by some reasonable means, this is the +first time You have received notice of non-compliance with this License +from such Contributor, and You become compliant prior to 30 days after +Your receipt of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent +infringement claim (excluding declaratory judgment actions, +counter-claims, and cross-claims) alleging that a Contributor Version +directly or indirectly infringes any patent, then the rights granted to +You by any and all Contributors for the Covered Software under Section +2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all +end user license agreements (excluding distributors and resellers) which +have been validly granted by You or Your distributors under this License +prior to termination shall survive termination. + +************************************************************************ +* * +* 6. Disclaimer of Warranty * +* ------------------------- * +* * +* Covered Software is provided under this License on an "as is" * +* basis, without warranty of any kind, either expressed, implied, or * +* statutory, including, without limitation, warranties that the * +* Covered Software is free of defects, merchantable, fit for a * +* particular purpose or non-infringing. The entire risk as to the * +* quality and performance of the Covered Software is with You. * +* Should any Covered Software prove defective in any respect, You * +* (not any Contributor) assume the cost of any necessary servicing, * +* repair, or correction. This disclaimer of warranty constitutes an * +* essential part of this License. No use of any Covered Software is * +* authorized under this License except under this disclaimer. * +* * +************************************************************************ + +************************************************************************ +* * +* 7. Limitation of Liability * +* -------------------------- * +* * +* Under no circumstances and under no legal theory, whether tort * +* (including negligence), contract, or otherwise, shall any * +* Contributor, or anyone who distributes Covered Software as * +* permitted above, be liable to You for any direct, indirect, * +* special, incidental, or consequential damages of any character * +* including, without limitation, damages for lost profits, loss of * +* goodwill, work stoppage, computer failure or malfunction, or any * +* and all other commercial damages or losses, even if such party * +* shall have been informed of the possibility of such damages. This * +* limitation of liability shall not apply to liability for death or * +* personal injury resulting from such party's negligence to the * +* extent applicable law prohibits such limitation. Some * +* jurisdictions do not allow the exclusion or limitation of * +* incidental or consequential damages, so this exclusion and * +* limitation may not apply to You. * +* * +************************************************************************ + +8. Litigation +------------- + +Any litigation relating to this License may be brought only in the +courts of a jurisdiction where the defendant maintains its principal +place of business and such litigation shall be governed by laws of that +jurisdiction, without reference to its conflict-of-law provisions. +Nothing in this Section shall prevent a party's ability to bring +cross-claims or counter-claims. + +9. Miscellaneous +---------------- + +This License represents the complete agreement concerning the subject +matter hereof. If any provision of this License is held to be +unenforceable, such provision shall be reformed only to the extent +necessary to make it enforceable. Any law or regulation which provides +that the language of a contract shall be construed against the drafter +shall not be used to construe this License against a Contributor. + +10. Versions of the License +--------------------------- + +10.1. New Versions + +Mozilla Foundation is the license steward. Except as provided in Section +10.3, no one other than the license steward has the right to modify or +publish new versions of this License. Each version will be given a +distinguishing version number. + +10.2. Effect of New Versions + +You may distribute the Covered Software under the terms of the version +of the License under which You originally received the Covered Software, +or under the terms of any subsequent version published by the license +steward. + +10.3. Modified Versions + +If you create software not governed by this License, and you want to +create a new license for such software, you may create and use a +modified version of this License if you rename the license and remove +any references to the name of the license steward (except to note that +such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary +Licenses + +If You choose to distribute Source Code Form that is Incompatible With +Secondary Licenses under the terms of this version of the License, the +notice described in Exhibit B of this License must be attached. + +Exhibit A - Source Code Form License Notice +------------------------------------------- + + This Source Code Form is subject to the terms of the Mozilla Public + License, v. 2.0. If a copy of the MPL was not distributed with this + file, You can obtain one at http://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular +file, then You may include the notice in a location (such as a LICENSE +file in a relevant directory) where a recipient would be likely to look +for such a notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice +--------------------------------------------------------- + + This Source Code Form is "Incompatible With Secondary Licenses", as + defined by the Mozilla Public License, v. 2.0. diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,5 @@ +# async-combinators + +[![Hackage](https://img.shields.io/hackage/v/async-combinators.svg)](https://hackage.haskell.org/package/async-combinators) +[![Build status](https://secure.travis-ci.org/serokell/async-combinators.svg)](https://travis-ci.org/serokell/async-combinators) +[![MPL-2.0 license](https://img.shields.io/badge/license-MPL--2.0-blue.svg)](https://github.com/serokell/async-combinators/blob/master/LICENSE) diff --git a/async-combinators.cabal b/async-combinators.cabal new file mode 100644 --- /dev/null +++ b/async-combinators.cabal @@ -0,0 +1,58 @@ +name: async-combinators +version: 0.0.0 +synopsis: Async combinators +description: Async combinators +homepage: https://github.com/serokell/async-combinators +bug-reports: https://github.com/serokell/async-combinators/issues +license: MPL-2.0 +license-file: LICENSE +author: @serokell +maintainer: Serokell +copyright: 2018 Serokell +category: Concurrency +build-type: Simple +extra-source-files: CHANGELOG.md + , README.md + +cabal-version: >=1.10 +tested-with: GHC == 8.0.2 + GHC == 8.2.2 + +library + hs-source-dirs: src + exposed-modules: Async.Combinators + ghc-options: -Wall + build-depends: base >= 4.7 && < 5 + , async >= 2.1 && < 2.2 + , safe-exceptions >= 0.1.6 && < 0.2 + , universum >= 1.1.0 && < 1.2 + , unliftio-core == 0.1.1.0 + default-language: Haskell2010 + default-extensions: NoImplicitPrelude + OverloadedStrings + RecordWildCards + ScopedTypeVariables + + +test-suite async-combinators-test + type: exitcode-stdio-1.0 + hs-source-dirs: test + main-is: Test.hs + other-modules: Test.Async.Combinators + build-depends: base >= 4.7 && <5 + , async-combinators + , universum + , HUnit + , hedgehog + , safe-exceptions + , tasty + , tasty-discover + , tasty-hedgehog + , tasty-hunit + build-tool-depends: tasty-discover:tasty-discover + ghc-options: -Wall -threaded -rtsopts -with-rtsopts=-N + default-language: Haskell2010 + default-extensions: NoImplicitPrelude + OverloadedStrings + RecordWildCards + ScopedTypeVariables diff --git a/src/Async/Combinators.hs b/src/Async/Combinators.hs new file mode 100644 --- /dev/null +++ b/src/Async/Combinators.hs @@ -0,0 +1,51 @@ +module Async.Combinators + ( -- * Running forever + WorkerExited (WorkerExited, WorkerFailed) + , withWorker + ) where + +import Universum + +import Control.Concurrent (myThreadId) +import Control.Concurrent.Async (withAsync) +import Control.Exception (asyncExceptionFromException, asyncExceptionToException) +import Control.Exception.Safe (Exception (..), finally, throwTo, tryAsync) +import Control.Monad.IO.Unlift (MonadUnliftIO, withRunInIO) + +import qualified GHC.Show as Show (Show (show)) + + +----------------------- +-- Running forever +----------------------- + +-- | Asynchronous exception thrown to the main thread if the worker exits. +data WorkerExited = WorkerExited Text -- ^ Worker returned + | WorkerFailed Text SomeException -- ^ Worker crashed + +instance Show WorkerExited where + show (WorkerExited n) = toString $ "Worker '" <> n <> "' returned" + show (WorkerFailed n e) = toString $ "Worker '" <> n <> "' failed: " <> show e + +instance Exception WorkerExited where + toException = asyncExceptionToException + fromException = asyncExceptionFromException + +-- | Like 'withAsync', but makes sure that the worker thread will +-- not exit, neither by returning, nor by throwing an exception. +-- If it exits, a 'WorkerExited' exception will be thrown in the current thread. +withWorker :: MonadUnliftIO m + => Text -- ^ Human-readable name for the forked thread + -> m () -- ^ Action performed by the worker + -> m b -- ^ Action performed in current thread + -> m b +withWorker name worker go = withRunInIO $ \run -> do + tid <- myThreadId + mainDone <- newIORef False + let worker' = do + res <- tryAsync $ run worker + unlessM (readIORef mainDone) $ throwTo tid $ + case res of + Right () -> WorkerExited name + Left e -> WorkerFailed name e + withAsync worker' $ \_ -> run go `finally` atomicWriteIORef mainDone True diff --git a/test/Test.hs b/test/Test.hs new file mode 100644 --- /dev/null +++ b/test/Test.hs @@ -0,0 +1,1 @@ +{-# OPTIONS_GHC -F -pgmF tasty-discover -optF --tree-display #-} diff --git a/test/Test/Async/Combinators.hs b/test/Test/Async/Combinators.hs new file mode 100644 --- /dev/null +++ b/test/Test/Async/Combinators.hs @@ -0,0 +1,116 @@ +module Test.Async.Combinators where + +import Universum + +import Control.Concurrent (killThread, myThreadId, threadDelay) +import Control.Exception (AsyncException (ThreadKilled)) +import Control.Exception.Safe (catchAny, handleAsync, isAsyncException, throw, throwTo, tryAsync) + +import Test.HUnit (Assertion, assertEqual, assertFailure, (@?)) + +import Async.Combinators + + +data TestException = TestException + deriving Show + +instance Exception TestException + +----------------------- +-- withWorker +----------------------- + +data WorkerTestResult = WorkerTestResult + { wtrReturn :: Either WorkerExited () + , wtrWorkerDone :: Bool + , wtrGoDone :: Bool + } + +withWorker_test :: IO () -> IO () -> IO WorkerTestResult +withWorker_test worker go = do + workerDone <- newIORef False + goDone <- newIORef False + + r <- tryAsync $ withWorker "worker" (worker *> writeIORef workerDone True) + (go *> writeIORef goDone True) + + WorkerTestResult r <$> readIORef workerDone <*> readIORef goDone + +assertWtr :: Bool -> Bool -> Bool -> WorkerTestResult -> Assertion +assertWtr expectRight expectWorkerDone expectGoDone WorkerTestResult{..} = do + assertEqual "return right" expectRight (isRight wtrReturn) + assertEqual "worker done" expectWorkerDone wtrWorkerDone + assertEqual "go done" expectGoDone wtrGoDone + + +-------- +-- First, some sanity checks. +-------- + +unit_withWorker_exception_is_async :: Assertion +unit_withWorker_exception_is_async = do + isAsyncException (WorkerExited "hi") @? "isAsync" + + me <- myThreadId + r <- tryAsync $ catchAny (throwTo me $ WorkerExited "hi") (const pass) + case r of + Right _ -> assertFailure $ "caught by safe `catchAny`" + Left (_ :: WorkerExited) -> pass + + +unit_withWorker_exception_can_be_caught :: Assertion +unit_withWorker_exception_can_be_caught = do + me <- myThreadId + handleAsync (\(_ :: WorkerExited) -> pass) $ throwTo me (WorkerExited "bye") + +-------- +-- Now actual tests. +-------- + +-- | Main thread exits -> worker is killed. +unit_withWorker_main_exit :: Assertion +unit_withWorker_main_exit = + withWorker_test (forever $ threadDelay 100) (threadDelay 100) >>= + assertWtr True False True + +-- | Main crashes -> worker is killed. +unit_withWorker_main_crash :: Assertion +unit_withWorker_main_crash = + withWorker_test (forever $ threadDelay 100) (throw TestException `catch` \TestException -> putText "Hi") >>= + assertWtr True False True + +-- | Worker exits -> main thread is killed. +unit_withWorker_worker_exit :: Assertion +unit_withWorker_worker_exit = + withWorker_test pass (threadDelay 100) >>= + assertWtr False True False + +-- | Worker crashes -> main thread is killed. +unit_withWorker_worker_crash :: Assertion +unit_withWorker_worker_crash = + withWorker_test (throw TestException) (threadDelay 100000) >>= + assertWtr False False False + +-- | Worker receives an async exception -> main thread is killed. +unit_withWorker_worker_crash_async :: Assertion +unit_withWorker_worker_crash_async = + withWorker_test worker (threadDelay 100000) >>= + assertWtr False False False + where + worker = myThreadId >>= \me -> throwTo me TestException + +-- | Worker receives ThreadKilled -> main thread is killed. +unit_withWorker_worker_crash_ThreadKilled :: Assertion +unit_withWorker_worker_crash_ThreadKilled = + withWorker_test worker (threadDelay 100000) >>= + assertWtr False False False + where + worker = myThreadId >>= \me -> throwTo me ThreadKilled + +-- | Main thread kills worker -> main thread is killed. +unit_withWorker_main_kills_worker :: Assertion +unit_withWorker_main_kills_worker = do + v <- newEmptyMVar + wtr <- withWorker_test (myThreadId >>= putMVar v >> threadDelay 1000000) + (takeMVar v >>= killThread >> threadDelay 1000000) + assertWtr False False False wtr