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See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this +when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) year name of author + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may +be called something other than `show w' and `show c'; they could even be +mouse-clicks or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + , 1 April 1989 + Ty Coon, President of Vice + +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/ascii-progress.cabal b/ascii-progress.cabal new file mode 100644 --- /dev/null +++ b/ascii-progress.cabal @@ -0,0 +1,51 @@ +name: ascii-progress +version: 0.1.0.0 +synopsis: A simple progress bar for the console. +-- description: +homepage: https://github.com/yamadapc/haskell-ascii-progress +license: GPL-2 +license-file: LICENSE +author: Pedro Tacla Yamada +maintainer: tacla.yamada@gmail.com +copyright: (c) 2015 Pedro Tacla Yamada +category: System +build-type: Simple +cabal-version: >=1.10 + +library + exposed-modules: System.Console.AsciiProgress + , System.Console.AsciiProgress.Internal + build-depends: MissingH + , ansi-terminal + , async >= 2.0.1.5 + , base >=4.7 && <4.8 + , data-default >= 0.5.3 + , time >= 1.4.2 + hs-source-dirs: lib + default-language: Haskell2010 + +executable example + main-is: Example.hs + build-depends: MissingH + , ansi-terminal + , async >= 2.0.1.5 + , base >=4.7 && <4.8 + , data-default >= 0.5.3 + , time >= 1.4.2 + hs-source-dirs: lib + , bin + default-language: Haskell2010 + +test-suite hspec + type: exitcode-stdio-1.0 + main-is: Spec.hs + build-depends: MissingH + , ansi-terminal + , async >= 2.0.1.5 + , base >=4.7 && <4.8 + , data-default >= 0.5.3 + , hspec >=2.1 && <3 + , time >= 1.4.2 + hs-source-dirs: lib + , test + default-language: Haskell2010 diff --git a/bin/Example.hs b/bin/Example.hs new file mode 100644 --- /dev/null +++ b/bin/Example.hs @@ -0,0 +1,16 @@ +import Control.Concurrent (threadDelay) +import Control.Monad (unless) +import System.Console.AsciiProgress (Options(..), isComplete, def, + newProgressBar, tick) + +main :: IO () +main = do + pg <- newProgressBar def { pgWidth = 100 } + loop pg + where + loop pg = do + b <- isComplete pg + unless b $ do + threadDelay $ 200 * 1000 + tick pg + loop pg diff --git a/lib/System/Console/AsciiProgress.hs b/lib/System/Console/AsciiProgress.hs new file mode 100644 --- /dev/null +++ b/lib/System/Console/AsciiProgress.hs @@ -0,0 +1,89 @@ +{-# LANGUAGE RecordWildCards #-} +module System.Console.AsciiProgress + ( ProgressBar(..) + , Options(..) + , Stats(..) + , isComplete + , newProgressBar + , tick + , tickN + , getProgressStrIO + , getProgressStats + , getProgressStr + -- Re-exports: + , Default(..) + ) + where + +import Control.Applicative ((<$>)) +import Control.Concurrent -- (Chan, MVar, modifyMVar, newChan, newEmptyMVar, + -- newMVar, readChan, readMVar, writeChan, modifyMVar_) +import Control.Concurrent.Async (Async, async, poll) +import Data.Default (Default(..)) +import Data.Maybe (isJust) +import System.Console.ANSI (clearLine, setCursorColumn) +import System.IO (BufferMode(..), hSetBuffering, stdout) + +import System.Console.AsciiProgress.Internal + +data ProgressBar = ProgressBar ProgressBarInfo (Async ()) + +-- | +-- Creates a new progress bar with the given @Options@ +newProgressBar :: Options -> IO ProgressBar +newProgressBar opts = do + hSetBuffering stdout NoBuffering + info <- newProgressBarInfo opts + future <- async $ start info + return $ ProgressBar info future + where + start info@ProgressBarInfo{..} = do + c <- readMVar pgCompleted + if c < pgTotal opts + then do + n <- readChan pgChannel + handleMessage n + if c + n < pgTotal opts + then start info + else reset + else reset + where + reset = do + clearLine + setCursorColumn 0 + handleMessage n = do + -- Update the completed tick count + modifyMVar_ pgCompleted (\c -> return (c + n)) + -- Find and update the current and first tick times: + stats <- getInfoStats info + reset + let progressStr = getProgressStr opts stats + putStr progressStr + +-- | +-- Tick the progress bar +tick :: ProgressBar -> IO () +tick pg = tickN pg 1 + +-- | +-- Tick the progress bar N times +tickN :: ProgressBar -> Int -> IO () +tickN (ProgressBar info _) = writeChan (pgChannel info) + +-- | +-- Returns if the progress bar rendering thread has exited (it has done enough +-- ticks) +isComplete :: ProgressBar -> IO Bool +isComplete (ProgressBar _ future) = isJust <$> poll future + +-- | +-- Gets the progress bar current @Stats @object +getProgressStats :: ProgressBar -> IO Stats +getProgressStats (ProgressBar info _) = getInfoStats info + +-- | +-- Like @getProgressStr@ but works on the @ProgressBar@ object and uses the IO +-- monad. +getProgressStrIO :: ProgressBar -> IO String +getProgressStrIO (ProgressBar info _) = + getProgressStr (pgOptions info) <$> getInfoStats info diff --git a/lib/System/Console/AsciiProgress/Internal.hs b/lib/System/Console/AsciiProgress/Internal.hs new file mode 100644 --- /dev/null +++ b/lib/System/Console/AsciiProgress/Internal.hs @@ -0,0 +1,164 @@ +{-# LANGUAGE LambdaCase #-} +{-# LANGUAGE RecordWildCards #-} +module System.Console.AsciiProgress.Internal + where + +import Control.Concurrent (Chan, MVar, newChan, newEmptyMVar, newMVar, + readMVar, tryPutMVar, tryReadMVar) +import Data.Default (Default(..)) +import Data.List.Utils (replace) +import Data.Time.Clock +import Text.Printf + +-- | +-- The progress bar's options. +data Options = Options { pgFormat :: String + -- ^ A format string for the progress bar. Currently the + -- following format strings are supported: + -- - ":eta" (ETA displayed in seconds) + -- - ":current" (current tick) + -- - ":total" (total number of ticks) + -- - ":percent" (percentage completed) + -- - ":elapsed" (elapsed time in seconds) + -- - ":bar" (the actual progress bar) + , pgCompletedChar :: Char + -- ^ Character to be used on the completed part of the + -- bar + , pgPendingChar :: Char + -- ^ Character to be used on the pending part of the bar + , pgTotal :: Int + -- ^ Total amount of ticks expected + , pgWidth :: Int + -- ^ The progress bar's width + } + deriving(Eq, Ord, Show) + +instance Default Options where + def = Options { pgFormat = "Working :percent [:bar] :current/:total " ++ + "(for :elapsed, :eta remaining)" + , pgCompletedChar = '=' + , pgPendingChar = ' ' + , pgTotal = 20 + , pgWidth = 80 + } + +-- | +-- The progress bar's state object. Contains all but the printing thread's +-- @Async@ object. +data ProgressBarInfo = ProgressBarInfo { pgOptions :: Options + , pgChannel :: Chan Int + , pgCompleted :: MVar Int + , pgFirstTick :: MVar UTCTime + } + deriving(Eq) + +-- | +-- Represents a point in time for the progress bar. +data Stats = Stats { stTotal :: Int + , stCompleted :: Int + , stRemaining :: Int + , stElapsed :: Double + , stPercent :: Double + , stEta :: Double + } + +-- | +-- Creates a new empty progress bar info object. +newProgressBarInfo :: Options -> IO ProgressBarInfo +newProgressBarInfo opts = do + chan <- newChan + mcompleted <- newMVar 0 + mfirstTick <- newEmptyMVar + return $ ProgressBarInfo opts chan mcompleted mfirstTick + +-- | +-- Gets the string to be printed given the options object and a certain stats +-- object representing the rendering moment. +getProgressStr :: Options -> Stats -> String +getProgressStr Options{..} Stats{..} = replace ":bar" barStr statsStr + where + statsStr = replaceMany + [ (":elapsed", printf "%3.1f" stElapsed) + , (":current", printf "%3d" stCompleted) + , (":total" , printf "%3d" stTotal) + , (":percent", printf "%3d%%" (floor (100 * stPercent) :: Int)) + , (":eta" , printf "%3.1f" stEta) + ] + pgFormat + barWidth = pgWidth - length (replace ":bar" "" statsStr) + barStr = getBar pgCompletedChar pgPendingChar barWidth stPercent + +-- | +-- Creates a stats object for a given @ProgressBarInfo@ node. This is the core +-- logic, isolated, and may be used to make the same analysis code to be used +-- by different progress renderers. +getInfoStats :: ProgressBarInfo -> IO Stats +getInfoStats info = do + completed <- readMVar (pgCompleted info) + currentTime <- getCurrentTime + initTime <- forceReadMVar (pgFirstTick info) currentTime + let total = pgTotal (pgOptions info) + remaining = total - completed + elapsed = getElapsed initTime currentTime + percent = fromIntegral completed / fromIntegral total + eta = getEta completed remaining elapsed + return $ Stats total completed remaining elapsed percent eta + +-- | +-- Generates the actual progress bar string, with its completed/pending +-- characters, width and a completeness percentage. +getBar :: Char -> Char -> Int -> Double -> String +getBar completedChar pendingChar width percent = + replicate bcompleted completedChar ++ replicate bremaining pendingChar + where + percentRemaining = 1 - percent + fwidth = fromIntegral width + bcompleted = ceiling $ fwidth * percent + bremaining = floor $ fwidth * percentRemaining + +-- | +-- Gets the amount of seconds elapsed between two @UTCTime@s as a double. +getElapsed :: UTCTime -> UTCTime -> Double +getElapsed initTime currentTime = realToFrac (diffUTCTime currentTime initTime) + +-- | +-- Gets the ETA, given the elapsed time and the amount of completed and +-- remaining ticks. +-- +-- >>> getEta 50 50 10.0 +-- 10.0 +-- >>> getEta 30 70 23.3 +-- 54.366666666666674 +getEta :: Int -> Int -> Double -> Double +getEta completed remaining elapsed = averageSecsPerTick * fromIntegral remaining + where + averageSecsPerTick = elapsed / fromIntegral completed + +-- | +-- Replaces each pair in a list of replacement pairs in a list with replace. +-- The idea is to call @(\(old, new) target -> replace old new target)@ on each +-- of the pairs, accumulating the resulting modified list. +-- +-- >>> replaceMany [] "foobar" +-- "foobar" +-- >>> replaceMany [("bar", "biz")] "foobar" +-- "foobiz" +-- >>> replaceMany [("foo", "baz"), ("bar", "biz")] "foobar" +-- "bazbiz" +replaceMany :: Eq a => [([a], [a])] -> [a] -> [a] +replaceMany pairs target = foldr (uncurry replace) target pairs + +-- | +-- Forces an MVar's contents to be read or swaped by a default value, even if +-- it's currently empty. Will discard the default value write to the MVar if it +-- becomes full in the middle of the operation and return its value. It's +-- assumed that once the MVar becomes full, it won't ever be left emptied. This +-- code may deadlock if that's the case. +forceReadMVar :: MVar a -> a -> IO a +forceReadMVar mv v = tryReadMVar mv >>= \case + Nothing -> do + success <- tryPutMVar mv v + if success + then return v + else readMVar mv + Just o -> return o diff --git a/test/Spec.hs b/test/Spec.hs new file mode 100644 --- /dev/null +++ b/test/Spec.hs @@ -0,0 +1,1 @@ +{-# OPTIONS_GHC -F -pgmF hspec-discover #-}