----------------------------------------------------------------------------- -- | -- Module : XMonad.Util.Loggers -- Copyright : (c) Brent Yorgey, Wirt Wolff -- License : BSD-style (see LICENSE) -- -- Maintainer : -- Stability : unstable -- Portability : unportable -- -- A collection of simple logger functions and formatting utilities -- which can be used in the 'XMonad.Hooks.DynamicLog.ppExtras' field of -- a pretty-printing status logger format. See "XMonad.Hooks.DynamicLog" -- for more information. ----------------------------------------------------------------------------- module XMonad.Util.Loggers ( -- * Usage -- $usage Logger -- * System Loggers -- $system , aumixVolume , battery , date , loadAvg , maildirNew, maildirUnread , logCmd , logFileCount -- * XMonad Loggers -- $xmonad , logCurrent, logLayout, logTitle -- * Formatting Utilities -- $format , onLogger , wrapL, fixedWidthL , logSp, padL , shortenL , dzenColorL, xmobarColorL , (<$>) ) where import XMonad (liftIO) import XMonad.Core import qualified XMonad.StackSet as W import XMonad.Hooks.DynamicLog import XMonad.Util.Font (Align (..)) import XMonad.Util.NamedWindows (getName) import Control.Applicative ((<$>)) import Data.List (isPrefixOf, isSuffixOf) import Data.Maybe (fromMaybe) import Data.Traversable (traverse) import System.Directory (getDirectoryContents) import System.IO import System.Locale import System.Process (runInteractiveCommand) import System.Time -- $usage -- Use this module by importing it into your @~\/.xmonad\/xmonad.hs@: -- -- > import XMonad.Util.Loggers -- -- Then, add one or more loggers to the -- 'XMonad.Hooks.DynamicLog.ppExtras' field of your -- 'XMonad.Hooks.DynamicLoc.PP', possibly with extra formatting . -- For example: -- -- > -- display load averages and a pithy quote along with xmonad status. -- > , logHook = dynamicLogWithPP $ defaultPP { -- > ppExtras = [ padL loadAvg, logCmd "fortune -n 40 -s" ] -- > } -- > -- gives something like " 3.27 3.52 3.26 Drive defensively. Buy a tank." -- -- See the formatting section below for another example using -- a @where@ block to define some formatted loggers for a top-level -- @myLogHook@. -- -- Loggers are named either for their function, as in 'battery', -- 'aumixVolume', and 'maildirNew', or are prefixed with \"log\" when -- making use of other functions or by analogy with the pp* functions. -- For example, the logger version of 'XMonad.Hooks.DynamicLog.ppTitle' -- is 'logTitle', and 'logFileCount' loggerizes the result of file -- counting code. -- -- Formatting utility names are generally as short as possible and -- carry the suffix \"L\". For example, the logger version of -- 'XMonad.Hooks.DynamicLog.shorten' is 'shortenL'. -- -- Of course, there is nothing really special about these so-called -- \"loggers\": they are just @X (Maybe String)@ actions. So you can -- use them anywhere you would use an @X (Maybe String)@, not just -- with DynamicLog. -- -- Additional loggers welcome! -- | 'Logger' is just a convenient synonym for @X (Maybe String)@. type Logger = X (Maybe String) -- $system -- | Get the current volume with @aumix@. aumixVolume :: Logger aumixVolume = logCmd "aumix -vq" -- | Get the battery status (percent charge and charging\/discharging -- status). This is an ugly hack and may not work for some people. -- At some point it would be nice to make this more general\/have -- fewer dependencies (assumes @\/usr\/bin\/acpi@ and @sed@ are installed.) battery :: Logger battery = logCmd "/usr/bin/acpi | sed -r 's/.*?: (.*%).*/\\1/; s/discharging, ([0-9]+%)/\\1-/; s/charging, ([0-9]+%)/\\1+/; s/charged, //'" -- | Get the current date and time, and format them via the -- given format string. The format used is the same as that used -- by the C library function strftime; for example, -- @date \"%a %b %d\"@ might display something like @Tue Feb 19@. -- For more information see something like -- . date :: String -> Logger date fmt = io $ do cal <- (getClockTime >>= toCalendarTime) return . Just $ formatCalendarTime defaultTimeLocale fmt cal -- | Get the load average. This assumes that you have a -- utility called @\/usr\/bin\/uptime@ and that you have @sed@ -- installed; these are fairly common on GNU\/Linux systems but it -- would be nice to make this more general. loadAvg :: Logger loadAvg = logCmd "/usr/bin/uptime | sed 's/.*: //; s/,//g'" -- | Create a 'Logger' from an arbitrary shell command. logCmd :: String -> Logger logCmd c = io $ do (_, out, _, _) <- runInteractiveCommand c fmap Just (hGetLine out) `catch` (const $ return Nothing) -- no need to waitForProcess, we ignore SIGCHLD -- | Get a count of filtered files in a directory. -- See 'maildirUnread' and 'maildirNew' source for usage examples. logFileCount :: FilePath -- ^ directory in which to count files -> (String -> Bool) -- ^ predicate to match if file should be counted -> Logger logFileCount d p = do c <- liftIO ( getDirectoryContents d) let n = length $ Prelude.filter p c case n of 0 -> return Nothing _ -> return $ Just $ show n -- | Get a count of unread mails in a maildir. For maildir format -- details, to write loggers for other classes of mail, see -- and 'logFileCount'. maildirUnread :: FilePath -> Logger maildirUnread mdir = logFileCount (mdir ++ "/cur/") (isSuffixOf ",") -- | Get a count of new mails in a maildir. maildirNew :: FilePath -> Logger maildirNew mdir = logFileCount (mdir ++ "/new/") (not . isPrefixOf ".") -- $xmonad -- -- A very small sample of what you can log since you have access to X. For -- example you can loggerize the number of windows on each workspace, or -- titles on other workspaces, or the id of the previously focused workspace.... -- | Get the title (name) of the focused window. logTitle :: Logger logTitle = withWindowSet $ traverse (fmap show . getName) . W.peek -- | Get the name of the current layout. logLayout :: Logger logLayout = withWindowSet $ return . Just . ld where ld = description . W.layout . W.workspace . W.current -- | Get the name of the current workspace. logCurrent :: Logger logCurrent = withWindowSet $ return . Just . W.currentTag -- $format -- Combine logger formatting functions to make your -- 'XMonad.Hooks.DynamicLog.ppExtras' more colorful and readable. -- (For convenience this module exports 'Control.Applicative.<$>' to -- use instead of \'.\' or \'$\' in hard to read formatting lines. -- For example: -- -- > myLogHook = dynamicLogWithPP defaultPP { -- > -- skipped -- > , ppExtras = [lLoad, lTitle, logSp 3, wrapL "[" "]" $ date "%a %d %b"] -- > , ppOrder = \(ws,l,_,xs) -> [l,ws] ++ xs -- > } -- > where -- > -- lTitle = fixedWidthL AlignCenter "." 99 . dzenColorL "cornsilk3" "" . padL . shortenL 80 $ logTitle -- > -- or something like: -- > lTitle = fixedWidthL AlignCenter "." 99 <$> dzenColorL "cornsilk3" "" <$> padL . shortenL 80 $ logTitle -- > -- > lLoad = dzenColorL "#6A5ACD" "" . wrapL loadIcon " " . padL $ loadAvg -- > loadIcon = " ^i(/home/me/.dzen/icons/load.xbm)" -- -- Note: When applying 'shortenL' or 'fixedWidthL' to logger strings -- containing colors or other formatting commands, apply the formatting -- /after/ the length adjustment, or include \"invisible\" characters -- in the length specification, e.g. in the above \'^fg(cornsilk3)\' and -- \'^fg()' yields 19 invisible and 80 visible characters. -- | Use a string formatting function to edit a 'Logger' string. -- For example, to create a tag function to prefix or label loggers, -- as in \'tag: output\', use: -- -- > tagL l = onLogger $ wrap (l ++ ": ") "" -- > -- > tagL "bat" battery -- > tagL "load" loadAvg -- -- If you already have a (String -> String) function you want to -- apply to a logger: -- -- > revL = onLogger trim -- -- See formatting utility source code for more 'onLogger' usage examples. onLogger :: (String -> String) -> Logger -> Logger onLogger = fmap . fmap -- | Wrap a logger's output in delimiters, unless it is @X (Nothing)@ -- or @X (Just \"\")@. Some examples: -- -- > wrapL " | " " | " (date "%a %d %b") -- ' | Tue 19 Feb | ' -- > -- > wrapL "bat: " "" battery -- ' bat: battery_logger_output' wrapL :: String -> String -> Logger -> Logger wrapL l r = onLogger $ wrap l r -- | Make a logger's output constant width by padding with the given string, -- /even if the logger is/ @X (Nothing)@ /or/ @X (Just \"\")@. Useful to -- reduce visual noise as a title logger shrinks and grows, to use a fixed -- width for a logger that sometimes becomes Nothing, or even to create -- fancy spacers or character based art effects. -- -- It fills missing logger output with a repeated character like \".\", -- \":\" or pattern, like \" -.-\". The cycling padding string is reversed on -- the left of the logger output. This is mainly useful with AlignCenter. fixedWidthL :: Align -- ^ AlignCenter, AlignRight, or AlignLeft -> String -- ^ String to cycle to pad missing logger output -> Int -- ^ Fixed length to output (including invisible formatting characters) -> Logger -> Logger fixedWidthL a str n logger = do mbl <- logger let l = fromMaybe "" mbl case a of AlignCenter -> toL (take n $ padhalf l ++ l ++ cs) AlignRight -> toL (reverse (take n $ reverse l ++ cs)) AlignLeft -> toL (take n $ l ++ cs) where toL = return . Just cs = cycle str padhalf x = reverse $ take ((n - length x) `div` 2) cs -- | Create a \"spacer\" logger, e.g. @logSp 3 -- loggerizes \' \'@. -- For more complex \"spacers\", use 'fixedWidthL' with @return Nothing@. logSp :: Int -> Logger logSp n = return . Just . take n $ cycle " " -- | Pad a logger's output with a leading and trailing space, unless it -- is @X (Nothing)@ or @X (Just \"\")@. padL :: Logger -> Logger padL = onLogger pad -- | Limit a logger's length, adding \"...\" if truncated. shortenL :: Int -> Logger -> Logger shortenL = onLogger . shorten -- | Color a logger's output with dzen foreground and background colors. -- -- > dzenColorL "green" "#2A4C3F" battery dzenColorL :: String -> String -> Logger -> Logger dzenColorL fg bg = onLogger $ dzenColor fg bg -- | Color a logger's output with xmobar foreground and background colors. -- -- > xmobarColorL "#6A5ACD" "gray6" loadAverage xmobarColorL :: String -> String -> Logger -> Logger xmobarColorL fg bg = onLogger $ xmobarColor fg bg -- todo -- * dynamicLogXinerama logger? Or sorted onscreen Id's with "current" indicator? -- is logCurrent really useful at all? -- -- * ppVisible, etc. Resolve code dup. somehow. Refactor DynamicLog so can -- be used for regular PP stuff /and/ loggers? -- -- * fns for "ppExtras as a whole", combine loggers more nicely. -- -- * parsers to use with fixedWidthL to be smarter about invisible characters?