WIP make new dependency module

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Nathan Dwarshuis 2022-06-19 15:42:11 -04:00
parent 5907035e9d
commit 4b3c99d495
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{-# LANGUAGE GADTs #-}
--------------------------------------------------------------------------------
-- | Functions for handling dependencies
module XMonad.Internal.DependencyX where
import Control.Monad.IO.Class
import Control.Monad.Identity
-- import Data.Aeson
import Data.Bifunctor
import Data.Either
import Data.List (find)
import Data.Maybe
-- import qualified Data.Text as T
import DBus
import DBus.Client
import DBus.Internal
import qualified DBus.Introspection as I
import System.Directory (findExecutable, readable, writable)
import System.Environment
import System.Exit
import XMonad.Core (X, io)
import XMonad.Internal.IO
import XMonad.Internal.Process
import XMonad.Internal.Shell
--------------------------------------------------------------------------------
-- | Feature
data AnyFeature p = FX (FeatureX p) | FIO (FeatureIO p)
type FeatureX p = Feature (X ()) Tree p
type FeatureIO p = Feature (IO ()) Tree p
data Feature a t p = Feature (FeatureData a t p) (Feature a t p)
| NoFeature
| ConstFeature a
printMsgs :: LogLevel -> [Msg] -> IO ()
printMsgs lvl ms = do
pn <- getProgName
mapM_ (printMsg pn lvl) ms
printMsg :: String -> LogLevel -> Msg -> IO ()
printMsg pname lvl (Msg ml mn msg)
| lvl > ml = putStrLn $ unwords [bracket pname, bracket mn, msg]
| otherwise = skip
where
bracket s = "[" ++ s ++ "]"
-- | Given a feature, return a monadic action if all dependencies are satisfied,
-- else Nothing (and print errors)
evalFeature :: Feature a ResultTree p -> ([Msg], Maybe a)
evalFeature (ConstFeature x) = ([], Just x)
evalFeature NoFeature = return Nothing
evalFeature (Feature f alt) =
either (\es -> first (++es) $ evalFeature alt) (\a -> ([], Just a))
$ evalFeatureData f
--------------------------------------------------------------------------------
-- | Feature Data
data FeatureData a t p = FeatureData
{ fdTree :: ActionTree a t p
, fdName :: String
, fdLevel :: LogLevel
}
data LogLevel = Silent | Error | Warn | Debug deriving (Eq, Show, Ord)
data Msg = Msg LogLevel String String
evalFeatureData :: FeatureData a ResultTree p -> Either [Msg] a
evalFeatureData FeatureData { fdTree = t, fdName = n, fdLevel = l } =
either (Left . fmap (Msg l n)) Right $ evalActionTree t
--------------------------------------------------------------------------------
-- | Action Tree
data ActionTree a t p =
IOTree (Action a p) (t (IODependency a t p) p)
| DBusTree (Action (Client -> a) p) (Maybe Client) (t (DBusDependency a t p) p)
data Action a p = Standalone a | Consumer (p -> a) (p -> p -> Result p)
evalActionTree :: ActionTree a ResultTree p -> Either [String] a
evalActionTree at = case at of
(IOTree a t) -> resolve a t
(DBusTree a (Just c) t) -> (\f -> f c) <$> resolve a t
-- TODO this is kinda redundant because I'll also get a message the dep tree
-- failing what I don't have a client
(DBusTree _ Nothing _) -> Left ["client not available to build action"]
where
resolve (Standalone f) t = const (Right f) =<< evalTreeNoop t
resolve (Consumer f combine) t = maybe noPayload (Right . f)
-- TODO not sure about this Right . Just thing, seems odd that I need it
=<< evalTree combine (Right . Just) t
noPayload = Left ["payload not available to build action"]
--------------------------------------------------------------------------------
-- | (Result) Tree
data Tree d p = And (Tree d p) (Tree d p) | Or (Tree d p) (Tree d p) | Only d
-- | how to interpret ResultTree combinations:
-- First (Success a) (Tree a) -> Or that succeeded on left
-- First (Fail a) (Tree a) -> And that failed on left
-- Both (Fail a) (Fail a) -> Or that failed
-- Both (Success a) (Success a) -> And that succeeded
-- Both (Fail a) (Success a) -> Or that failed first and succeeded second
-- Both (Success a) (Fail a) -> And that failed on the right
data ResultTree d p =
First (ResultTree d p) (Tree d p)
| Both (ResultTree d p) (ResultTree d p)
| Success d (Maybe p)
| Fail d [String]
-- | Given an updated condition tree, collect all evaluations and return a
-- combined evaluation (which may be Nothing, Something, or an error). Must also
-- supply a function to combine Results in the corner case where two And
-- arguments are successful and have non-empty outputs.
evalTree :: (p -> p -> Result p) -> (p -> Result p) -> ResultTree a p -> Result p
evalTree f2 f1 = go (Right Nothing)
where
go acc (First a _) = case go acc a of
-- Or succeeds on left
(Right p) -> combine p =<< acc
-- And fails on left
(Left e) -> Left e
go acc (Both a b) = case (go acc a, go acc b) of
-- And succeeds
(Right pa, Right pb) -> combine pb =<< combine pa =<< acc
-- Or fails both
(Left ea, Left eb) -> addErrors acc (ea ++ eb)
-- And fails on right
(Right _, Left eb) -> addErrors acc eb
-- Or succeeds on right
(Left ea, Right pb) -> either (Left . (ea ++)) (combine pb) acc
go acc (Success _ p) = combine p =<< acc
go acc (Fail _ e) = addErrors acc e
addErrors cur new = Left $ new ++ fromLeft [] cur
combine (Just a) (Just b) = f2 a b
combine (Just a) Nothing = f1 a
combine Nothing (Just b) = f1 b
combine _ _ = Right Nothing
evalTreeNoop :: ResultTree a p -> Result p
evalTreeNoop = evalTree (const . evalNil) evalNil
mapMTree :: Monad m => (d -> m (Result p)) -> Tree d p
-> m (ResultTree d p)
mapMTree f = fmap snd . go
where
go (And a b) = doTest a b True
go (Or a b) = doTest a b False
go (Only a) = either (\x -> (False, Fail a x)) (\x -> (True, Success a x))
<$> f a
doTest a b useAnd = do
(success, ra) <- go a
let try2nd = if useAnd then success else not success
if try2nd then second (Both ra) <$> go b else return (success, First ra b)
--------------------------------------------------------------------------------
-- | Dependency
data IODependency a t p = Executable Bool FilePath
| AccessiblePath FilePath Bool Bool
| IOTest String (IO (Maybe String))
| IORead String (IO (Either String (Maybe p)))
| Systemd UnitType String
| NestedFeature (Feature a t p)
data UnitType = SystemUnit | UserUnit deriving (Eq, Show)
data DBusDependency a e p =
Bus BusName
| Endpoint BusName ObjectPath InterfaceName DBusMember
| DBusIO (IODependency a e p)
data DBusMember = Method_ MemberName
| Signal_ MemberName
| Property_ String
deriving (Eq, Show)
--------------------------------------------------------------------------------
-- | Result
type Result p = Either [String] (Maybe p)
evalNil :: p -> Result q
evalNil = const $ Right Nothing
evalFail :: String -> Result p
evalFail msg = Left [msg]
-- | Given a condition tree, evaluate all dependencies according to 'fill in'
-- the results (which may either be Nothing, a returned payload to use for the
-- action, or an error.
updateIOConditions :: Tree (IODependency a Tree p) p -> IO (ResultTree (IODependency a Tree p) p)
updateIOConditions = mapMTree testIODependency
updateDBusConditions :: Client -> Tree (DBusDependency a Tree p) p
-> IO (ResultTree (DBusDependency a Tree p) p)
updateDBusConditions client = mapMTree (evalDBusDependency client)
--------------------------------------------------------------------------------
-- | IO Dependency
testIODependency :: IODependency a Tree p -> IO (Result p)
testIODependency (Executable _ bin) = maybe err evalNil <$> findExecutable bin
where
err = Left ["executable '" ++ bin ++ "' not found"]
testIODependency (IOTest _ t) = maybe (Right Nothing) (Left . (:[])) <$> t
testIODependency (IORead _ t) = either (Left . (:[])) Right <$> t
testIODependency (Systemd t n) = do
(rc, _, _) <- readCreateProcessWithExitCode' (shell cmd) ""
return $ case rc of
ExitSuccess -> Right Nothing
_ -> Left ["systemd " ++ unitType t ++ " unit '" ++ n ++ "' not found"]
where
cmd = fmtCmd "systemctl" $ ["--user" | t == UserUnit] ++ ["status", n]
unitType SystemUnit = "system"
unitType UserUnit = "user"
testIODependency (AccessiblePath p r w) = do
res <- getPermissionsSafe p
let msg = permMsg res
return msg
where
testPerm False _ _ = Nothing
testPerm True f res = Just $ f res
permMsg NotFoundError = evalFail "file not found"
permMsg PermError = evalFail "could not get permissions"
permMsg (PermResult res) =
case (testPerm r readable res, testPerm w writable res) of
(Just False, Just False) -> evalFail "file not readable or writable"
(Just False, _) -> evalFail "file not readable"
(_, Just False) -> evalFail "file not writable"
_ -> Right Nothing
testIODependency (NestedFeature ftr) = go ftr
where
go (Feature (FeatureData { fdTree = t }) alt) =
-- TODO add feature name to messages
case t of
(IOTree a ct) -> evalFun a <$> updateIOConditions ct
(DBusTree a (Just client) ct) -> evalFun a <$> updateDBusConditions client ct
(DBusTree _ Nothing _) -> failMaybe alt ["client not found"]
where
failMaybe NoFeature msg = return $ Left msg
failMaybe f _ = go f
evalFun (Standalone _) = evalTreeNoop
evalFun (Consumer _ f) = evalTree f (return . return)
go _ = return $ Right Nothing
--------------------------------------------------------------------------------
-- | DBus Dependency Result
introspectInterface :: InterfaceName
introspectInterface = interfaceName_ "org.freedesktop.DBus.Introspectable"
introspectMethod :: MemberName
introspectMethod = memberName_ "Introspect"
evalDBusDependency :: Client -> DBusDependency a Tree p -> IO (Result p)
evalDBusDependency client (Bus bus) = do
ret <- callMethod client queryBus queryPath queryIface queryMem
return $ case ret of
Left e -> evalFail e
Right b -> let ns = bodyGetNames b in
if bus' `elem` ns then Right Nothing
else evalFail $ unwords ["name", singleQuote bus', "not found on dbus"]
where
bus' = formatBusName bus
queryBus = busName_ "org.freedesktop.DBus"
queryIface = interfaceName_ "org.freedesktop.DBus"
queryPath = objectPath_ "/"
queryMem = memberName_ "ListNames"
bodyGetNames [v] = fromMaybe [] $ fromVariant v :: [String]
bodyGetNames _ = []
evalDBusDependency client (Endpoint busname objpath iface mem) = do
ret <- callMethod client busname objpath introspectInterface introspectMethod
return $ case ret of
Left e -> evalFail e
Right body -> procBody body
where
procBody body = let res = findMem =<< I.parseXML objpath =<< fromVariant
=<< listToMaybe body in
case res of
Just True -> Right Nothing
_ -> evalFail $ fmtMsg' mem
findMem = fmap (matchMem mem)
. find (\i -> I.interfaceName i == iface)
. I.objectInterfaces
matchMem (Method_ n) = elemMember n I.methodName I.interfaceMethods
matchMem (Signal_ n) = elemMember n I.signalName I.interfaceSignals
matchMem (Property_ n) = elemMember n I.propertyName I.interfaceProperties
elemMember n fname fmember = elem n . fmap fname . fmember
fmtMem (Method_ n) = "method " ++ singleQuote (formatMemberName n)
fmtMem (Signal_ n) = "signal " ++ singleQuote (formatMemberName n)
fmtMem (Property_ n) = "property " ++ singleQuote n
fmtMsg' m = unwords
[ "could not find"
, fmtMem m
, "on interface"
, singleQuote $ formatInterfaceName iface
, "on bus"
, formatBusName busname
]
evalDBusDependency _ (DBusIO d) = testIODependency d