1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
{-# LANGUAGE PackageImports #-}
{-# LANGUAGE DataKinds #-}
module Propellor.Engine (
mainProperties,
runPropellor,
ensureProperty,
ensureChildProperties,
fromHost,
fromHost',
onlyProcess,
) where
import System.Exit
import System.IO
import Data.Monoid
import "mtl" Control.Monad.RWS.Strict
import System.PosixCompat
import System.Posix.IO
import System.FilePath
import System.Directory
import Control.Applicative
import Prelude
import Propellor.Types
import Propellor.Message
import Propellor.Exception
import Propellor.Info
import Propellor.Property
import Utility.Exception
-- | Gets the Properties of a Host, and ensures them all,
-- with nice display of what's being done.
mainProperties :: Host -> IO ()
mainProperties host = do
ret <- runPropellor host $ ensureChildProperties [toChildProperty overall]
messagesDone
case ret of
FailedChange -> exitWith (ExitFailure 1)
_ -> exitWith ExitSuccess
where
overall :: Property (MetaTypes '[])
overall = property "overall" $
ensureChildProperties (hostProperties host)
-- | Runs a Propellor action with the specified host.
--
-- If the Result is not FailedChange, any EndActions
-- that were accumulated while running the action
-- are then also run.
runPropellor :: Host -> Propellor Result -> IO Result
runPropellor host a = do
(res, endactions) <- evalRWST (runWithHost a) host ()
endres <- mapM (runEndAction host res) endactions
return $ mconcat (res:endres)
runEndAction :: Host -> Result -> EndAction -> IO Result
runEndAction host res (EndAction desc a) = actionMessageOn (hostName host) desc $ do
(ret, _s, _) <- runRWST (runWithHost (catchPropellor (a res))) host ()
return ret
-- | Ensures the child properties, with a display of each as it runs.
ensureChildProperties :: [ChildProperty] -> Propellor Result
ensureChildProperties ps = ensure ps NoChange
where
ensure [] rs = return rs
ensure (p:ls) rs = do
hn <- asks hostName
r <- actionMessageOn hn (getDesc p) (catchPropellor $ getSatisfy p)
ensure ls (r <> rs)
-- | Lifts an action into the context of a different host.
--
-- > fromHost hosts "otherhost" Ssh.getHostPubKey
fromHost :: [Host] -> HostName -> Propellor a -> Propellor (Maybe a)
fromHost l hn getter = case findHost l hn of
Nothing -> return Nothing
Just h -> Just <$> fromHost' h getter
fromHost' :: Host -> Propellor a -> Propellor a
fromHost' h getter = do
(ret, _s, runlog) <- liftIO $ runRWST (runWithHost getter) h ()
tell runlog
return ret
onlyProcess :: FilePath -> IO a -> IO a
onlyProcess lockfile a = bracket lock unlock (const a)
where
lock = do
createDirectoryIfMissing True (takeDirectory lockfile)
l <- createFile lockfile stdFileMode
setLock l (WriteLock, AbsoluteSeek, 0, 0)
`catchIO` const alreadyrunning
return l
unlock = closeFd
alreadyrunning = error "Propellor is already running on this host!"
|