feat!: add AsyncPipe abstraction, significantly improve throughput of Transform streams

package.json

@@ -3,10 +3,11 @@
   "version": "v1.6.1",
   "type": "module",
   "dependencies": {
-    "csv-parse": "^5.5.5",
+    "csv-parse": "^5.5.6",
-    "csv-stringify": "^6.4.6"
+    "csv-stringify": "^6.5.0"
   },
   "devDependencies": {
+    "cbor-x": "^1.5.9",
     "typescript": "^5.4.5"
   }
 }

spago.lock

@@ -5,20 +5,26 @@ workspace:
       dependencies:
         - aff: ">=7.1.0 <8.0.0"
         - arrays: ">=7.3.0 <8.0.0"
+        - console
+        - control: ">=6.0.0 <7.0.0"
+        - datetime
         - effect: ">=4.0.0 <5.0.0"
         - either: ">=6.1.0 <7.0.0"
         - exceptions: ">=6.0.0 <7.0.0"
         - foldable-traversable: ">=6.0.0 <7.0.0"
         - foreign-object: ">=4.1.0 <5.0.0"
+        - fork: ">=6.0.0 <7.0.0"
         - lists: ">=7.0.0 <8.0.0"
         - maybe: ">=6.0.0 <7.0.0"
         - mmorph: ">=7.0.0 <8.0.0"
+        - newtype
         - node-buffer: ">=9.0.0 <10.0.0"
         - node-event-emitter: ">=3.0.0 <4.0.0"
         - node-fs: ">=9.1.0 <10.0.0"
         - node-path: ">=5.0.0 <6.0.0"
         - node-streams: ">=9.0.0 <10.0.0"
         - node-zlib: ">=0.4.0 <0.5.0"
+        - now
         - ordered-collections: ">=3.2.0 <4.0.0"
         - parallel: ">=6.0.0 <7.0.0"
         - pipes: ">=8.0.0 <9.0.0"

spago.yaml

@@ -12,20 +12,26 @@ package:
   dependencies:
     - aff: ">=7.1.0 <8.0.0"
     - arrays: ">=7.3.0 <8.0.0"
+    - console: ">=6.1.0 <7.0.0"
+    - control: ">=6.0.0 <7.0.0"
+    - datetime: ">=6.1.0 <7.0.0"
     - effect: ">=4.0.0 <5.0.0"
     - either: ">=6.1.0 <7.0.0"
     - exceptions: ">=6.0.0 <7.0.0"
     - foldable-traversable: ">=6.0.0 <7.0.0"
     - foreign-object: ">=4.1.0 <5.0.0"
+    - fork: ">=6.0.0 <7.0.0"
     - lists: ">=7.0.0 <8.0.0"
     - maybe: ">=6.0.0 <7.0.0"
     - mmorph: ">=7.0.0 <8.0.0"
+    - newtype: ">=5.0.0 <6.0.0"
     - node-buffer: ">=9.0.0 <10.0.0"
     - node-event-emitter: ">=3.0.0 <4.0.0"
     - node-fs: ">=9.1.0 <10.0.0"
     - node-path: ">=5.0.0 <6.0.0"
     - node-streams: ">=9.0.0 <10.0.0"
     - node-zlib: ">=0.4.0 <0.5.0"
+    - now: ">=6.0.0 <7.0.0"
     - ordered-collections: ">=3.2.0 <4.0.0"
     - parallel: ">=6.0.0 <7.0.0"
     - pipes: ">=8.0.0 <9.0.0"

src/Pipes.Async.purs

@@ -0,0 +1,281 @@
+module Pipes.Async where
+
+import Prelude hiding (join)
+
+import Control.Alternative (class Alternative, empty, guard)
+import Control.Monad.Error.Class (class MonadError, catchError, throwError)
+import Control.Monad.Except (ExceptT, runExceptT)
+import Control.Monad.Fork.Class (class MonadBracket, class MonadFork, fork)
+import Control.Monad.Maybe.Trans (runMaybeT)
+import Control.Monad.Morph (hoist)
+import Control.Monad.Rec.Class (class MonadRec, Step(..), forever, tailRecM)
+import Control.Monad.ST.Class (liftST)
+import Control.Monad.ST.Ref (STRef)
+import Control.Monad.ST.Ref as ST.Ref
+import Control.Monad.Trans.Class (lift)
+import Control.Parallel (class Parallel, parOneOf)
+import Data.Array (fold)
+import Data.Array as Array
+import Data.DateTime.Instant as Instant
+import Data.Either (Either(..), either)
+import Data.Generic.Rep (class Generic)
+import Data.Maybe (Maybe(..), isNothing)
+import Data.Newtype (unwrap)
+import Data.Show.Generic (genericShow)
+import Data.Time.Duration (Milliseconds)
+import Data.Traversable (traverse_)
+import Data.Tuple.Nested (type (/\), (/\))
+import Effect.Aff.Class (class MonadAff)
+import Effect.Class (liftEffect)
+import Effect.Console (log)
+import Effect.Exception (Error)
+import Effect.Now as Now
+import Pipes (await, yield)
+import Pipes.Collect as Collect
+import Pipes.Core (Pipe, Producer, Proxy)
+
+data WriteSignal
+  = WriteSignalOk
+  | WriteSignalEnded
+derive instance Generic WriteSignal _
+derive instance Eq WriteSignal
+derive instance Ord WriteSignal
+instance Show WriteSignal where show = genericShow
+
+instance Discard WriteSignal where
+  discard = bind
+
+data ReadSignal
+  = ReadSignalOk
+  | ReadSignalEnded
+
+derive instance Generic ReadSignal _
+derive instance Eq ReadSignal
+derive instance Ord ReadSignal
+instance Show ReadSignal where show = genericShow
+
+instance Discard ReadSignal where
+  discard = bind
+
+data WriteResult
+  = WriteAgain
+  | WriteNeedsDrain
+  | WriteEnded
+derive instance Generic WriteResult _
+derive instance Eq WriteResult
+derive instance Ord WriteResult
+instance Show WriteResult where show = genericShow
+
+data ReadResult a
+  = ReadOk a
+  | ReadWouldBlock
+derive instance Generic (ReadResult a) _
+derive instance Eq a => Eq (ReadResult a)
+derive instance Ord a => Ord (ReadResult a)
+derive instance Functor ReadResult
+instance Show a => Show (ReadResult a) where show = genericShow
+
+-- | An `AsyncPipe` is a `Pipe`-like struct that allows
+-- | concurrently reading from a `Producer` and writing to a `Consumer`.
+-- |
+-- | An implementation of `AsyncPipe` for Node `Transform` streams
+-- | is provided in `Pipes.Node.Stream`.
+-- |
+-- | ## Fields
+-- | - `m x`
+-- |    - Initializer
+-- | - `x -> a -> m WriteResult`
+-- |    - Write a value `a` to the underlying resource
+-- | - `x -> m WriteSignal`
+-- |    - Block until the pipe is writable again (or writing must stop)
+-- | - `x -> m (ReadResult b)`
+-- |    - Attempt to read a chunk
+-- | - `x -> m ReadSignal`
+-- |    - Block until the pipe is readable again (or reading must stop)
+data AsyncPipe x a b m =
+  AsyncPipe
+    (m x)
+    (x -> a -> m WriteResult)
+    (x -> m WriteSignal)
+    (x -> m (ReadResult b))
+    (x -> m ReadSignal)
+
+-- | Wraps all fields of an `AsyncPipe` with logging to debug
+-- | behavior and timing.
+debug :: forall x a b m. MonadAff m => String -> AsyncPipe x a b m -> AsyncPipe x a b m
+debug c (AsyncPipe init write awaitWrite read awaitRead) =
+  let
+    logL m = liftEffect $ log $ "[" <> c <> "] " <> m
+    logR m = liftEffect $ log $ "[" <> c <> "] " <> fold (Array.replicate 20 " ") <> m
+
+    time :: forall a'. m a' -> m (Milliseconds /\ a')
+    time m = do
+      start <- liftEffect Now.now
+      a <- m
+      end <- liftEffect Now.now
+      pure $ (end `Instant.diff` start) /\ a
+
+    init' = do
+      logL "init >"
+      elapsed /\ x <- time init
+      logL $ "< init " <> "(" <> show (unwrap elapsed) <> "ms)"
+      pure x
+
+    write' x a = do
+      logL "write >"
+      elapsed /\ w <- time $ write x a
+      logL $ "< write " <> show w <> " (" <> show (unwrap elapsed) <> "ms)"
+      pure w
+
+    read' x = do
+      logR "read >"
+      elapsed /\ r <- time $ read x
+      logR $ "< read " <> show (r $> unit) <> " (" <> show (unwrap elapsed) <> "ms)"
+      pure r
+
+    awaitWrite' x = do
+      logL "awaitWrite >"
+      elapsed /\ w <- time $ awaitWrite x
+      logL $ "< awaitWrite " <> show w <> " (" <> show (unwrap elapsed) <> "ms)"
+      pure w
+
+    awaitRead' x = do
+      logR "awaitRead >"
+      elapsed /\ r <- time $ awaitRead x
+      logR $ "< awaitRead " <> show r <> " (" <> show (unwrap elapsed) <> "ms)"
+      pure r
+  in
+    AsyncPipe init' write' awaitWrite' read' awaitRead'
+
+-- | Convert an `AsyncPipe` to a regular `Pipe`.
+-- |
+-- | Rather than two concurrently-running halves (producer & consumer),
+-- | this requires the `AsyncPipe` to occasionally stop `await`ing data
+-- | written by the upstream `Producer` so that it can `yield` to the downstream `Consumer`.
+-- |
+-- | This implementation chooses to prioritize `yield`ing data to the `Consumer` over
+-- | `await`ing written chunks.
+-- |
+-- | Note that using this limits the potential parallelism of the entire pipeline, ex:
+-- |
+-- | ```purs
+-- | Pipe.FS.read "foo.csv"        -- read
+-- |   >-> sync Pipe.CSV.parse     -- parse
+-- |   >-> sync Pipe.CBOR.encode   -- encode
+-- |   >-> Pipe.FS.write "foo.bin" -- write
+-- | ```
+-- |
+-- | In the above example, this is what happens when the pipeline
+-- | is executed:
+-- | 1. `write` asks `encode` "do you have any data yet?" (fast)
+-- | 1. `encode` asks `parse` "do you have any data yet?" (fast)
+-- | 1. `parse` asks `read` "do you have any data yet?" (fast)
+-- | 1. `read` passes 1 chunk to `parse` (fast)
+-- | 1. `parse` blocks until the chunk is parsed (slow)
+-- | 1. `parse` passes 1 chunk to `encode` (fast)
+-- | 1. `encode` blocks until the chunk is encoded (slow)
+-- | 1. `write` writes the block (fast)
+-- |
+-- | For larger workloads, changing this to use `asyncPipe` would be preferable, ex:
+-- | ```purs
+-- | Pipe.FS.read "foo.csv"        -- read
+-- |   >-/-> Pipe.CSV.parse        -- parse
+-- |   >-/-> Pipe.CBOR.encode      -- encode
+-- |   >-> Pipe.FS.write "foo.bin" -- write
+-- | ```
+-- |
+-- | With this change:
+-- | * `read` will pass chunks to `parse` as fast as `parse` allows
+-- | * `parse` will parse chunks and yield them to `encode` as soon as they're ready
+-- | * `encode` will encode chunks and yield them to `write` as soon as they're ready
+sync :: forall x a b f p e m. MonadError e m => Alternative p => Parallel p m => MonadFork f m => MonadAff m => AsyncPipe x (Maybe a) (Maybe b) m -> Pipe (Maybe a) (Maybe b) m Unit
+sync (AsyncPipe init write awaitWrite read awaitRead) =
+  let
+    liftPipe :: forall r. (Proxy _ _ _ _ m) r -> ExceptT (Step _ _) (Proxy _ _ _ _ m) r
+    liftPipe = lift
+
+    liftM :: forall r. m r -> ExceptT (Step _ _) (Proxy _ _ _ _ m) r
+    liftM = liftPipe <<< lift
+
+    continue a = throwError (Loop a)
+    break = throwError (Done unit)
+
+    awaitRW x = parOneOf [Right <$> awaitWrite x, Left <$> awaitRead x]
+
+    wSignal WriteSignalOk = WriteAgain
+    wSignal WriteSignalEnded = WriteEnded
+  in do
+    x <- lift init
+    flip tailRecM WriteAgain
+      \w ->
+      map (either identity identity)
+      $ runExceptT do
+          rb <- liftM $ read x
+          case rb of
+            ReadWouldBlock
+              | w == WriteEnded -> liftM (awaitRead x) *> continue w
+              | w == WriteNeedsDrain -> liftM (awaitRW x) >>= either (const $ continue w) (continue <<< wSignal)
+              | otherwise -> pure unit
+            ReadOk (Just b) -> liftPipe (yield $ Just b) *> continue w
+            ReadOk Nothing -> liftPipe (yield Nothing) *> break
+
+          when (w /= WriteAgain) $ continue w
+
+          a <- liftPipe await
+          w' <- liftM $ write x a
+          when (isNothing a) $ continue WriteEnded
+          pure $ Loop w'
+
+-- | Implementation of `(>-/->)`
+-- |
+-- | In the current `MonadFork` "thread", read data from the `AsyncPipe` as it
+-- | is yielded and `yield` to the downstream `Consumer`.
+-- |
+-- | Concurrently, in a separate thread, read data from the upstream `Producer`
+-- | and write to the `AsyncPipe` at max throughput.
+-- |
+-- | If the producing half fails, the error is caught and rethrown.
+-- |
+-- | If the consuming half fails, the error is caught, the producing half is killed, and the error is rethrown.
+pipeAsync
+  :: forall f m x a b
+   . MonadRec m
+  => MonadAff m
+  => MonadBracket Error f m
+  => Producer (Maybe a) m Unit
+  -> AsyncPipe x (Maybe a) (Maybe b) m
+  -> Producer (Maybe b) m Unit
+pipeAsync prod (AsyncPipe init write awaitWrite read awaitRead) =
+  do
+    errST :: STRef _ (Maybe Error) <- lift $ liftEffect $ liftST $ ST.Ref.new Nothing
+    killST :: STRef _ Boolean <- lift $ liftEffect $ liftST $ ST.Ref.new false
+
+    let
+      killThread = void $ liftEffect $ liftST $ ST.Ref.write true killST
+      threadKilled = liftEffect $ liftST $ ST.Ref.read killST
+      putThreadError = void <<< liftEffect <<< liftST <<< flip ST.Ref.write errST <<< Just
+      getThreadError = liftEffect $ liftST $ ST.Ref.read errST
+
+      rx x a = do
+        killed <- threadKilled
+        guard $ not killed
+        w <- lift $ write x a
+        case w of
+          WriteNeedsDrain -> lift $ void $ awaitWrite x
+          WriteEnded -> empty
+          WriteAgain -> pure unit
+
+      spawn = lift <<< fork <<< flip catchError putThreadError
+
+    x <- lift init
+    _thread <- spawn $ void $ runMaybeT $ Collect.foreach (rx x) (hoist lift prod)
+
+    forever do
+      getThreadError >>= traverse_ throwError
+      rb <- lift $ read x
+      case rb of
+        ReadOk (Just b) -> yield $ Just b
+        ReadOk Nothing -> killThread *> yield Nothing
+        ReadWouldBlock -> void $ lift (awaitRead x)
+
+infixl 7 pipeAsync as >-/->

src/Pipes.Collect.purs

@@ -31,12 +31,8 @@ traverse :: forall a b m. MonadRec m => (b -> a -> m b) -> b -> Producer a m Uni
 traverse f b0 p0 =
   flip tailRecM (p0 /\ b0) \(p /\ b) ->
     case p of
-      Respond a m -> do
+      Respond a m -> Loop <$> (m unit /\ _) <$> f b a
-        b' <- f b a
+      M m -> Loop <$> (_ /\ b) <$> m
-        pure $ Loop $ m unit /\ b'
-      M m -> do
-        n <- m
-        pure $ Loop $ (n /\ b)
       Request _ _ -> pure $ Done b
       Pure _ -> pure $ Done b
 

src/Pipes.Node.Stream.purs

@@ -3,20 +3,26 @@ module Pipes.Node.Stream where
 import Prelude hiding (join)
 
 import Control.Monad.Error.Class (class MonadThrow, throwError)
-import Control.Monad.Rec.Class (class MonadRec, Step(..), tailRecM, whileJust)
+import Control.Monad.Rec.Class (class MonadRec, Step(..), tailRecM)
 import Control.Monad.ST.Class (liftST)
+import Control.Monad.ST.Global (Global)
+import Control.Monad.ST.Ref (STRef)
+import Control.Monad.ST.Ref as ST.Ref
 import Control.Monad.ST.Ref as STRef
 import Control.Monad.Trans.Class (lift)
-import Control.Parallel (parOneOf)
 import Data.Maybe (Maybe(..), maybe)
-import Data.Traversable (for_, traverse, traverse_)
+import Data.Traversable (for_, traverse_)
 import Data.Tuple.Nested ((/\))
+import Effect (Effect)
 import Effect.Aff.Class (class MonadAff, liftAff)
-import Effect.Class (liftEffect)
+import Effect.Class (class MonadEffect, liftEffect)
 import Effect.Exception (Error)
+import Node.Stream.Object (WriteResult(..), maybeReadResult)
 import Node.Stream.Object as O
 import Pipes (await, yield)
 import Pipes (for) as P
+import Pipes.Async (AsyncPipe(..))
+import Pipes.Async as AsyncPipe
 import Pipes.Core (Consumer, Pipe, Producer, Producer_)
 import Pipes.Util (InvokeResult(..), invoke)
 
@@ -84,49 +90,78 @@ fromWritable w = do
 
   tailRecM go unit
 
--- | Convert a `Transform` stream to a `Pipe`.
+newtype TransformContext a b =
--- |
+  TransformContext
--- | When `Nothing` is piped to this, the `Transform` stream will
+    { stream :: O.Transform a b
--- | be `end`ed, and the pipe will noop if invoked again.
+    , removeErrorListener :: Effect Unit
-fromTransform :: forall a b m. MonadThrow Error m => MonadAff m => O.Transform a b -> Pipe (Maybe a) (Maybe b) m Unit
+    , errorST :: STRef Global (Maybe Error)
-fromTransform t = do
+    }
-  { error: errorST, cancel: removeErrorListener } <- liftEffect $ O.withErrorST t
+
+transformCleanup :: forall m a b. MonadEffect m => TransformContext a b -> m Unit
+transformCleanup (TransformContext {removeErrorListener}) = do
+  liftEffect removeErrorListener
+
+transformStream :: forall a b. TransformContext a b -> O.Transform a b
+transformStream (TransformContext {stream}) = stream
+
+transformRethrow :: forall m a b. MonadThrow Error m => MonadEffect m => TransformContext a b -> m Unit
+transformRethrow (TransformContext {errorST}) = traverse_ throwError =<< liftEffect (liftST $ ST.Ref.read errorST)
+
+-- | Convert a `Transform` stream to an `AsyncPipe`.
+fromTransform
+  :: forall a b m
+   . MonadThrow Error m
+  => MonadAff m
+  => Effect (O.Transform a b)
+  -> AsyncPipe (TransformContext a b) (Maybe a) (Maybe b) m
+fromTransform t =
   let
-    maybeThrow = traverse_ throwError =<< liftEffect (liftST $ STRef.read errorST)
+    init = do
-
+      stream <- liftEffect t
-    cleanup = do
+      { error: errorST, cancel: removeErrorListener } <- liftEffect $ O.withErrorST stream
-      flip tailRecM unit $ const do
+      pure $ TransformContext {errorST, removeErrorListener, stream}
-        liftAff $ O.awaitReadableOrClosed t
+    write x Nothing = do
-        readEnded <- liftEffect $ O.isReadableEnded t
+      let s = transformStream x
-        yieldWhileReadable
+      liftEffect $ O.end s
-        pure $ (if readEnded then Done else Loop) unit
+      pure AsyncPipe.WriteEnded
-
+    write x (Just a) = do
-      liftAff $ O.awaitFinished t
+      transformRethrow x
-      maybeThrow
+      let s = transformStream x
-      liftEffect $ removeErrorListener
+      w <- liftEffect $ O.write s a
-      yield Nothing
+      pure $ case w of
-
+        WriteOk -> AsyncPipe.WriteAgain
-    yieldWhileReadable = void $ whileJust $ maybeYield1
+        WriteWouldBlock -> AsyncPipe.WriteNeedsDrain
-
+    awaitWrite x = do
-    maybeYield1 = traverse (\a -> yield (Just a) $> Just unit) =<< O.maybeReadResult <$> liftEffect (O.read t)
+      transformRethrow x
-
+      let s = transformStream x
-    onEOS = liftEffect (O.end t) *> cleanup $> Done unit
+      liftAff $ O.awaitWritableOrClosed s
-    onChunk a = liftEffect (O.write t a) $> Loop unit
+      ended <- liftEffect $ O.isWritableEnded s
-
+      if ended then
-    go _ = do
+        pure $ AsyncPipe.WriteSignalEnded
-      maybeThrow
+      else do
-      needsDrain <- liftEffect $ O.needsDrain t
+        liftAff $ O.awaitWritableOrClosed s
-      ended <- liftEffect $ O.isWritableEnded t
+        pure $ AsyncPipe.WriteSignalOk
-      if needsDrain then do
+    read x =
-        yieldWhileReadable
+      do
-        liftAff $ parOneOf [O.awaitWritableOrClosed t, O.awaitReadableOrClosed t]
+        transformRethrow x
-        pure $ Loop unit
+        let s = transformStream x
-      else if ended then
+        readEnded <- liftEffect $ O.isReadableEnded s
-        cleanup $> Done unit
+        if readEnded then do
+          transformCleanup x
+          pure $ AsyncPipe.ReadOk Nothing
         else
-        await >>= maybe onEOS onChunk
+          maybe AsyncPipe.ReadWouldBlock (AsyncPipe.ReadOk <<< Just) <$> maybeReadResult <$> liftEffect (O.read s)
-
+    awaitRead x = do
-  tailRecM go unit
+      transformRethrow x
+      let s = transformStream x
+      ended <- liftEffect $ O.isReadableEnded s
+      if ended then
+        pure $ AsyncPipe.ReadSignalEnded
+      else do
+        liftAff $ O.awaitReadableOrClosed s
+        pure $ AsyncPipe.ReadSignalOk
+  in
+    AsyncPipe init write awaitWrite read awaitRead
 
 -- | Given a `Producer` of values, wrap them in `Just`.
 -- |

src/Pipes.Node.Zlib.purs

@@ -12,31 +12,34 @@ import Node.Buffer (Buffer)
 import Node.Stream.Object as O
 import Node.Zlib as Zlib
 import Node.Zlib.Types (ZlibStream)
-import Pipes.Core (Pipe)
+import Pipes.Async (AsyncPipe)
-import Pipes.Node.Stream (fromTransform)
+import Pipes.Node.Stream (TransformContext, fromTransform)
 
-fromZlib :: forall r m. MonadAff m => MonadThrow Error m => Effect (ZlibStream r) -> Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+type X = TransformContext Buffer Buffer
-fromZlib z = do
+
+fromZlib :: forall r m. MonadAff m => MonadThrow Error m => Effect (ZlibStream r) -> AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
+fromZlib z =
+  fromTransform do
     raw <- liftEffect $ Zlib.toDuplex <$> z
-  fromTransform $ O.unsafeCoerceTransform raw
+    pure $ O.unsafeCoerceTransform raw
 
-gzip :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+gzip :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 gzip = fromZlib Zlib.createGzip
 
-gunzip :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+gunzip :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 gunzip = fromZlib Zlib.createGunzip
 
-unzip :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+unzip :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 unzip = fromZlib Zlib.createUnzip
 
-inflate :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+inflate :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 inflate = fromZlib Zlib.createInflate
 
-deflate :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+deflate :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 deflate = fromZlib Zlib.createDeflate
 
-brotliCompress :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+brotliCompress :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 brotliCompress = fromZlib Zlib.createBrotliCompress
 
-brotliDecompress :: forall m. MonadAff m => MonadThrow Error m => Pipe (Maybe Buffer) (Maybe Buffer) m Unit
+brotliDecompress :: forall m. MonadAff m => MonadThrow Error m => AsyncPipe X (Maybe Buffer) (Maybe Buffer) m
 brotliDecompress = fromZlib Zlib.createBrotliDecompress

src/Pipes.Util.purs

@@ -149,3 +149,5 @@ invoke m a =
         Pure _ -> pure Exited
   in
     go (IDidNotAwait m)
+
+

test/Test/Main.purs

@@ -3,18 +3,19 @@ module Test.Main where
 import Prelude
 
 import Data.Maybe (Maybe(..))
+import Data.Time.Duration (Milliseconds(..))
 import Effect (Effect)
 import Effect.Aff (launchAff_)
-import Test.Pipes.Node.Stream as Test.Pipes.Node.Stream
-import Test.Pipes.Node.Buffer as Test.Pipes.Node.Buffer
-import Test.Pipes.Node.FS as Test.Pipes.Node.FS
 import Test.Pipes.Collect as Test.Pipes.Collect
 import Test.Pipes.Construct as Test.Pipes.Construct
+import Test.Pipes.Node.Buffer as Test.Pipes.Node.Buffer
+import Test.Pipes.Node.FS as Test.Pipes.Node.FS
+import Test.Pipes.Node.Stream as Test.Pipes.Node.Stream
 import Test.Spec.Reporter (specReporter)
 import Test.Spec.Runner (defaultConfig, runSpec')
 
 main :: Effect Unit
-main = launchAff_ $ runSpec' (defaultConfig { exit = false, timeout = Nothing }) [ specReporter ] do
+main = launchAff_ $ runSpec' (defaultConfig { slow = Milliseconds 0.0, failFast = true, exit = false, timeout = Nothing }) [ specReporter ] do
   Test.Pipes.Node.Stream.spec
   Test.Pipes.Node.Buffer.spec
   Test.Pipes.Node.FS.spec

test/Test/Pipes.Node.Stream.js

@@ -1,4 +1,16 @@
 import Stream from 'stream'
+import * as CBOR from "cbor-x";
+import * as CSVDecode from "csv-parse";
+import * as CSVEncode from "csv-stringify";
+
+export const cborDecode = () => new CBOR.DecoderStream({useRecords: false, allowHalfOpen: true});
+export const cborEncode = () => new CBOR.EncoderStream({useRecords: false, allowHalfOpen: true});
+
+export const cborDecodeSync = a => () => CBOR.decodeMultiple(a);
+export const cborEncodeSync = a => () => CBOR.encode(a, {useRecords: false});
+
+export const csvDecode = () => CSVDecode.parse({columns: true, allowHalfOpen: true})
+export const csvEncode = () => CSVEncode.stringify({header: true, allowHalfOpen: true})
 
 export const discardTransform = () => new Stream.Transform({
   transform: function(_ck, _enc, cb) {
@@ -7,6 +19,16 @@ export const discardTransform = () => new Stream.Transform({
   objectMode: true
 })
 
+export const slowTransform = () => {
+  return new Stream.Transform({
+  transform: function(ck, _enc, cb) {
+    this.push(ck)
+    setTimeout(() => cb(), 4)
+  },
+  objectMode: true
+})
+}
+
 export const charsTransform = () => new Stream.Transform({
   transform: function(ck, _enc, cb) {
     ck.split('').filter(s => !!s).forEach(s => this.push(s))

test/Test/Pipes.Node.Stream.purs

@@ -2,49 +2,72 @@ module Test.Pipes.Node.Stream where
 
 import Prelude
 
-import Control.Monad.Trans.Class (lift)
+import Control.Monad.Cont (lift)
+import Control.Monad.Error.Class (liftEither)
+import Control.Monad.Except (runExcept)
 import Data.Array as Array
-import Data.Foldable (fold)
+import Data.Bifunctor (lmap)
+import Data.Either (Either(..))
+import Data.Foldable (fold, intercalate)
+import Data.FoldableWithIndex (forWithIndex_)
+import Data.FunctorWithIndex (mapWithIndex)
+import Data.Int as Int
 import Data.List ((:))
 import Data.List as List
 import Data.Maybe (Maybe)
 import Data.Newtype (wrap)
+import Data.Profunctor.Strong (first)
+import Data.String as String
 import Data.String.Gen (genAlphaString)
+import Data.Traversable (for_, traverse)
 import Data.Tuple.Nested (type (/\), (/\))
 import Effect (Effect)
 import Effect.Aff (Aff, delay)
 import Effect.Class (class MonadEffect, liftEffect)
+import Effect.Exception (error)
+import Effect.Unsafe (unsafePerformEffect)
+import Foreign (Foreign)
 import Node.Buffer (Buffer)
 import Node.Buffer as Buffer
 import Node.Encoding (Encoding(..))
 import Node.FS.Stream as FS.Stream
 import Node.FS.Sync as FS
 import Node.Stream.Object as O
-import Node.Zlib as Zlib
+import Pipes (each) as Pipe
-import Pipes (each) as Pipes
 import Pipes (yield, (>->))
+import Pipes.Async (sync, (>-/->))
+import Pipes.Collect as Pipe.Collect
 import Pipes.Core (Consumer, Producer, runEffect)
-import Pipes.Node.Buffer as Pipes.Buffer
+import Pipes.Node.Buffer as Pipe.Buffer
-import Pipes.Node.Stream as S
+import Pipes.Node.FS as Pipe.FS
-import Pipes.Prelude (mapFoldable, toListM) as Pipes
+import Pipes.Node.Stream as Pipe.Node
-import Simple.JSON (writeJSON)
+import Pipes.Node.Zlib as Pipe.Zlib
-import Test.Common (jsonParse, jsonStringify, tmpFile, tmpFiles)
+import Pipes.Prelude (toListM) as Pipe
+import Simple.JSON (readImpl, readJSON, writeJSON)
+import Test.Common (jsonStringify, tmpFile, tmpFiles)
 import Test.QuickCheck.Arbitrary (arbitrary)
 import Test.QuickCheck.Gen (randomSample')
 import Test.Spec (Spec, around, describe, it)
-import Test.Spec.Assertions (shouldEqual)
+import Test.Spec.Assertions (fail, shouldEqual)
 
 foreign import readableFromArray :: forall @a. Array a -> O.Readable a
 foreign import discardTransform :: forall a b. Effect (O.Transform a b)
+foreign import slowTransform :: forall a b. Effect (O.Transform a b)
 foreign import charsTransform :: Effect (O.Transform String String)
+foreign import cborEncodeSync :: forall a. a -> Effect Buffer
+foreign import cborDecodeSync :: forall a. Buffer -> Effect a
+foreign import cborEncode :: forall a. Effect (O.Transform a Buffer)
+foreign import cborDecode :: forall a. Effect (O.Transform Buffer a)
+foreign import csvEncode :: forall a. Effect (O.Transform a String)
+foreign import csvDecode :: forall a. Effect (O.Transform String a)
 
 writer :: forall m. MonadEffect m => String -> m (O.Writable Buffer /\ Consumer (Maybe Buffer) Aff Unit)
 writer a = do
   stream <- liftEffect $ O.unsafeCoerceWritable <$> FS.Stream.createWriteStream a
-  pure $ stream /\ S.fromWritable stream
+  pure $ stream /\ Pipe.Node.fromWritable stream
 
 reader :: forall m. MonadEffect m => String -> m (Producer (Maybe Buffer) Aff Unit)
-reader a = liftEffect $ S.fromReadable <$> O.unsafeCoerceReadable <$> FS.Stream.createReadStream a
+reader a = liftEffect $ Pipe.Node.fromReadable <$> O.unsafeCoerceReadable <$> FS.Stream.createReadStream a
 
 spec :: Spec Unit
 spec =
@@ -52,30 +75,30 @@ spec =
     describe "Readable" do
       describe "Readable.from(<Iterable>)" do
         it "empty" do
-          vals <- Pipes.toListM $ (S.fromReadable $ readableFromArray @{ foo :: String } []) >-> S.unEOS
+          vals <- Pipe.toListM $ (Pipe.Node.fromReadable $ readableFromArray @{ foo :: String } []) >-> Pipe.Node.unEOS
           vals `shouldEqual` List.Nil
         it "singleton" do
-          vals <- Pipes.toListM $ (S.fromReadable $ readableFromArray @{ foo :: String } [ { foo: "1" } ]) >-> S.unEOS
+          vals <- Pipe.toListM $ (Pipe.Node.fromReadable $ readableFromArray @{ foo :: String } [ { foo: "1" } ]) >-> Pipe.Node.unEOS
           vals `shouldEqual` ({ foo: "1" } : List.Nil)
         it "many elements" do
           let exp = (\n -> { foo: show n }) <$> Array.range 0 100
-          vals <- Pipes.toListM $ (S.fromReadable $ readableFromArray exp) >-> S.unEOS
+          vals <- Pipe.toListM $ (Pipe.Node.fromReadable $ readableFromArray exp) >-> Pipe.Node.unEOS
           vals `shouldEqual` (List.fromFoldable exp)
     describe "Writable" $ around tmpFile do
       describe "fs.WriteStream" do
         it "pipe to file" \p -> do
           stream <- O.unsafeCoerceWritable <$> liftEffect (FS.Stream.createWriteStream p)
           let
-            w = S.fromWritable stream
+            w = Pipe.Node.fromWritable stream
             source = do
               buf <- liftEffect $ Buffer.fromString "hello" UTF8
               yield buf
-          runEffect $ S.withEOS source >-> w
+          runEffect $ Pipe.Node.withEOS source >-> w
           contents <- liftEffect $ FS.readTextFile UTF8 p
           contents `shouldEqual` "hello"
           shouldEqual true =<< liftEffect (O.isWritableEnded stream)
         it "async pipe to file" \p -> do
-          w <- S.fromWritable <$> O.unsafeCoerceWritable <$> liftEffect (FS.Stream.createWriteStream p)
+          w <- Pipe.Node.fromWritable <$> O.unsafeCoerceWritable <$> liftEffect (FS.Stream.createWriteStream p)
           let
             source = do
               yield "hello, "
@@ -87,7 +110,7 @@ spec =
               yield "this is a "
               lift $ delay $ wrap 5.0
               yield "test."
-          runEffect $ S.withEOS (source >-> Pipes.Buffer.fromString UTF8) >-> w
+          runEffect $ Pipe.Node.withEOS (source >-> Pipe.Buffer.fromString UTF8) >-> w
           contents <- liftEffect $ FS.readTextFile UTF8 p
           contents `shouldEqual` "hello, world! this is a test."
         it "chained pipes" \p -> do
@@ -101,40 +124,96 @@ spec =
           let
             exp = fold (writeJSON <$> objs)
           stream /\ w <- liftEffect $ writer p
-          runEffect $ S.withEOS (Pipes.each objs >-> jsonStringify >-> Pipes.Buffer.fromString UTF8) >-> w
+          runEffect $ Pipe.Node.withEOS (Pipe.each objs >-> jsonStringify >-> Pipe.Buffer.fromString UTF8) >-> w
           contents <- liftEffect $ FS.readTextFile UTF8 p
           contents `shouldEqual` exp
           shouldEqual true =<< liftEffect (O.isWritableEnded stream)
     describe "Transform" do
-      it "gzip" do
       let
-          json = yield $ writeJSON { foo: "bar" }
+        bignums = Array.range 1 1000
-          exp = "1f8b0800000000000003ab564acbcf57b2524a4a2c52aa0500eff52bfe0d000000"
+        firstNames = String.split (wrap "\n") $ unsafePerformEffect (FS.readTextFile UTF8 "./test/Test/first_names.txt")
-        gzip <- S.fromTransform <$> O.unsafeCoerceTransform <$> liftEffect (Zlib.toDuplex <$> Zlib.createGzip)
+        lastNames = String.split (wrap "\n") $ unsafePerformEffect (FS.readTextFile UTF8 "./test/Test/last_names.txt")
-        outs :: List.List String <- Pipes.toListM (S.withEOS (json >-> Pipes.Buffer.fromString UTF8) >-> gzip >-> S.unEOS >-> Pipes.Buffer.toString Hex)
+        names n = do
-        fold outs `shouldEqual` exp
+          first <- firstNames
-      around tmpFiles
+          last <- Array.take (Int.round $ Int.toNumber n / Int.toNumber (Array.length firstNames)) lastNames
-        $ it "file >-> gzip >-> file >-> gunzip" \(a /\ b) -> do
+          pure $ first <> " " <> last
-            liftEffect $ FS.writeTextFile UTF8 a $ writeJSON [ 1, 2, 3, 4 ]
+        people n = mapWithIndex (\ix name -> {id: show $ ix + 1, name}) (names n)
-            areader <- liftEffect $ reader a
+        peopleCSV n = "id,name\n" <> intercalate "\n" ((\{id, name} -> id <> "," <> name) <$> people n)
-            bwritestream /\ bwriter <- liftEffect $ writer b
-            gzip <- S.fromTransform <$> O.unsafeCoerceTransform <$> liftEffect (Zlib.toDuplex <$> Zlib.createGzip)
-            runEffect $ areader >-> gzip >-> bwriter
-            shouldEqual true =<< liftEffect (O.isWritableEnded bwritestream)
 
-            gunzip <- S.fromTransform <$> O.unsafeCoerceTransform <$> liftEffect (Zlib.toDuplex <$> Zlib.createGunzip)
+      for_ [4000, 8000, 32000, 64000, 200000] \n -> do
-            breader <- liftEffect $ reader b
+        let
-            nums <- Pipes.toListM (breader >-> gunzip >-> S.unEOS >-> Pipes.Buffer.toString UTF8 >-> jsonParse @(Array Int) >-> Pipes.mapFoldable identity)
+          csv = peopleCSV n
-            Array.fromFoldable nums `shouldEqual` [ 1, 2, 3, 4 ]
+          people' = people n
+        around tmpFiles
+          $ it (show n <> " row csv >-/-> csv-parse >-/-> cborEncode") \(a /\ _) -> do
+              liftEffect $ FS.writeTextFile UTF8 a csv
+              cbor :: Buffer <- Pipe.Collect.toBuffer
+                $ Pipe.FS.read a
+                  >-> Pipe.Node.inEOS (Pipe.Buffer.toString UTF8)
+                  >-/-> Pipe.Node.fromTransform csvDecode
+                  >-/-> Pipe.Node.fromTransform cborEncode
+                  >-> Pipe.Node.unEOS
+              f :: Array Foreign <- liftEffect $ cborDecodeSync cbor
+              ppl <- traverse (liftEither <<< lmap (error <<< show) <<< runExcept <<< readImpl) f
+              ppl `shouldEqual` people'
+
+        around tmpFiles
+          $ it (show n <> " row csv >-> sync csv-parse >-> sync cborEncode") \(a /\ _) -> do
+              liftEffect $ FS.writeTextFile UTF8 a csv
+              cbor :: Buffer <- Pipe.Collect.toBuffer
+                $ Pipe.FS.read a
+                  >-> Pipe.Node.inEOS (Pipe.Buffer.toString UTF8)
+                  >-> sync (Pipe.Node.fromTransform csvDecode)
+                  >-> sync (Pipe.Node.fromTransform cborEncode)
+                  >-> Pipe.Node.unEOS
+              f :: Array Foreign <- liftEffect $ cborDecodeSync cbor
+              ppl <- traverse (liftEither <<< lmap (error <<< show) <<< runExcept <<< readImpl) f
+              ppl `shouldEqual` people'
+
+      around tmpFiles
+        $ it "file >-> sync gzip >-> sync gunzip" \(a /\ _) -> do
+            liftEffect $ FS.writeTextFile UTF8 a $ writeJSON bignums
+            json <- Pipe.Collect.toMonoid
+              $ Pipe.FS.read a
+                >-> sync Pipe.Zlib.gzip
+                >-> sync Pipe.Zlib.gunzip
+                >-> Pipe.Node.unEOS
+                >-> Pipe.Buffer.toString UTF8
+            readJSON json `shouldEqual` (Right bignums)
+
+      around tmpFiles
+        $ it "file >-/-> gzip >-/-> slow >-/-> gunzip" \(a /\ _) -> do
+            liftEffect $ FS.writeTextFile UTF8 a $ writeJSON bignums
+            json <-
+              Pipe.Collect.toMonoid
+              $ Pipe.FS.read a
+                >-/-> Pipe.Zlib.gzip
+                >-/-> Pipe.Node.fromTransform slowTransform
+                >-/-> Pipe.Zlib.gunzip
+                >-> Pipe.Node.unEOS
+                >-> Pipe.Buffer.toString UTF8
+
+            readJSON json `shouldEqual` (Right bignums)
+      around tmpFiles
+        $ it "file >-> sync gzip >-> sync slow >-> sync gunzip" \(a /\ _) -> do
+            liftEffect $ FS.writeTextFile UTF8 a $ writeJSON bignums
+            json <-
+              Pipe.Collect.toMonoid
+              $ Pipe.FS.read a
+                >-> sync Pipe.Zlib.gzip
+                >-> sync (Pipe.Node.fromTransform slowTransform)
+                >-> sync Pipe.Zlib.gunzip
+                >-> Pipe.Node.unEOS
+                >-> Pipe.Buffer.toString UTF8
+
+            readJSON json `shouldEqual` (Right bignums)
       around tmpFile $ it "file >-> discardTransform" \(p :: String) -> do
         liftEffect $ FS.writeTextFile UTF8 p "foo"
         r <- reader p
-        discard' <- liftEffect discardTransform
+        out :: List.List Int <- Pipe.toListM $ r >-/-> Pipe.Node.fromTransform discardTransform >-> Pipe.Node.unEOS
-        out :: List.List Int <- Pipes.toListM $ r >-> S.fromTransform discard' >-> S.unEOS
         out `shouldEqual` List.Nil
       around tmpFile $ it "file >-> charsTransform" \(p :: String) -> do
         liftEffect $ FS.writeTextFile UTF8 p "foo bar"
         r <- reader p
-        chars' <- liftEffect charsTransform
+        out :: List.List String <- Pipe.toListM $ r >-> Pipe.Node.inEOS (Pipe.Buffer.toString UTF8) >-/-> Pipe.Node.fromTransform charsTransform >-> Pipe.Node.unEOS
-        out :: List.List String <- Pipes.toListM $ r >-> S.inEOS (Pipes.Buffer.toString UTF8) >-> S.fromTransform chars' >-> S.unEOS
         out `shouldEqual` List.fromFoldable [ "f", "o", "o", " ", "b", "a", "r" ]