ascii-progress (empty) → 0.1.0.0
raw patch · 7 files changed
+662/−0 lines, 7 filesdep +MissingHdep +ansi-terminaldep +asyncsetup-changed
Dependencies added: MissingH, ansi-terminal, async, base, data-default, hspec, time
Files
- LICENSE +339/−0
- Setup.hs +2/−0
- ascii-progress.cabal +51/−0
- bin/Example.hs +16/−0
- lib/System/Console/AsciiProgress.hs +89/−0
- lib/System/Console/AsciiProgress/Internal.hs +164/−0
- test/Spec.hs +1/−0
+ LICENSE view
@@ -0,0 +1,339 @@+ GNU GENERAL PUBLIC LICENSE+ Version 2, June 1991++ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA+ Everyone is permitted to copy and distribute verbatim copies+ of this license document, but changing it is not allowed.++ Preamble++ The licenses for most software are designed to take away your+freedom to share and change it. By contrast, the GNU General Public+License is intended to guarantee your freedom to share and change free+software--to make sure the software is free for all its users. This+General Public License applies to most of the Free Software+Foundation's software and to any other program whose authors commit to+using it. (Some other Free Software Foundation software is covered by+the GNU Lesser General Public License instead.) You can apply it to+your programs, too.++ When we speak of free software, we are referring to freedom, not+price. 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+ Setup.hs view
@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain
+ ascii-progress.cabal view
@@ -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
+ bin/Example.hs view
@@ -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
+ lib/System/Console/AsciiProgress.hs view
@@ -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
+ lib/System/Console/AsciiProgress/Internal.hs view
@@ -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
+ test/Spec.hs view
@@ -0,0 +1,1 @@+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}