================================================ D-Bus implementation for Haskell (dbus-core_0.9) ================================================ This is the first significant release to dbus-core in a while, and it contains some significant improvements to both the API and implementation. Users are advised to upgrade, as the 0.8 branch will no longer be receiving improvements or corrections. * Release announcement: https://john-millikin.com/releases/dbus-core/0.9/ * API documentation: http://hackage.haskell.org/package/dbus-core * Source code (literate PDF): https://john-millikin.com/downloads/dbus-core_0.9.pdf * Source code (tarball): https://john-millikin.com/downloads/dbus-core_0.9.tar.gz Changes in release 0.9 ====================== The biggest change in this release is that dbus-client has been merged into dbus-core. The original purpose of dbus-client (as a very high-level, often-updated support library) never materialized, and the split packaging caused issues with dependencies and versioning. The parts of dbus-client that were commonly used were moved into the DBus.Client and DBus.Client.Simple modules. Users are highly encouraged to use these modules in their applications. Other changes and improvements include: * The Array, Dictionary, and Structure types are no longer needed for most users. You can cast containers directly to corresponding standard types, such as Vector and Map. * Smart constructors for magic strings have been renamed so they're easier to read and type; for example, mkBusName is now just busName. * Support for custom transports and authentication mechanisms. * Removed some seldom-used modules, such as MatchRule and NameReservation. Their functionality has been merged into the new client modules. * Performance improvements for marshaling and unmarshaling messages. How to use the new simple client API ==================================== The new API makes calling and exporting methods very easy; take a look at these examples! Getting a list of connected clients ----------------------------------- {-# LANGUAGE OverloadedStrings #-} module Main (main) where import Data.List (sort) import DBus.Client.Simple main :: IO () main = do client <- connectSession -- Request a list of connected clients from the bus bus <- proxy client "org.freedesktop.DBus" "/org/freedesktop/DBus" reply <- call bus "org.freedesktop.DBus" "ListNames" [] -- org.freedesktop.DBus.ListNames returns a single value, which is -- a list of names. let Just names = fromVariant (reply !! 0) -- Print each name on a line, sorted so reserved names are below -- temporary names. mapM_ putStrLn (sort names) Exporting methods ----------------- {-# LANGUAGE OverloadedStrings #-} module Main (main) where import Control.Concurrent (threadDelay) import Control.Monad (forever) import DBus.Client.Simple onEcho :: String -> IO String onEcho str = do putStrLn str return str onDivide :: Double -> Double -> IO Double onDivide x y = if y == 0 then throwError "com.example.DivisionByZero" "Divided by zero" [] else return (x / y) main :: IO () main = do client <- connectSession -- Request a unique name on the bus. If the name is already -- in use, continue without it. requestName client "com.example.ExportExample" [] -- Export an example object at "/divide" export client "/divide" [ method "com.example.Echo" "Echo" onEcho , method "com.example.Math" "Divide" onDivide ] -- Wait forever for method calls forever (threadDelay 50000)