summaryrefslogtreecommitdiff
path: root/Remote/Rsync.hs
blob: 3216567479ad22dd9566769ccea79adc98141b72 (plain)
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
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
{- A remote that is only accessible by rsync.
 -
 - Copyright 2011 Joey Hess <joey@kitenet.net>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Remote.Rsync (remote) where

import qualified Data.ByteString.Lazy.Char8 as L
import qualified Data.Map as M

import Common.Annex
import Types.Remote
import qualified Git
import Logs.UUID
import Config
import Annex.Content
import Remote.Helper.Special
import Remote.Helper.Encryptable
import Crypto
import Utility.RsyncFile

type RsyncUrl = String

data RsyncOpts = RsyncOpts {
	rsyncUrl :: RsyncUrl,
	rsyncOptions :: [CommandParam]
}

remote :: RemoteType Annex
remote = RemoteType {
	typename = "rsync",
	enumerate = findSpecialRemotes "rsyncurl",
	generate = gen,
	setup = rsyncSetup
}

gen :: Git.Repo -> UUID -> Maybe RemoteConfig -> Annex (Remote Annex)
gen r u c = do
	o <- genRsyncOpts r
	cst <- remoteCost r expensiveRemoteCost
	return $ encryptableRemote c
		(storeEncrypted o)
		(retrieveEncrypted o)
		Remote {
			uuid = u,
			cost = cst,
			name = Git.repoDescribe r,
 			storeKey = store o,
			retrieveKeyFile = retrieve o,
			removeKey = remove o,
			hasKey = checkPresent r o,
			hasKeyCheap = False,
			config = Nothing,
			repo = r
		}

genRsyncOpts :: Git.Repo -> Annex RsyncOpts
genRsyncOpts r = do
	url <- getConfig r "rsyncurl" (error "missing rsyncurl")
	opts <- getConfig r "rsync-options" ""
	return $ RsyncOpts url $ map Param $ filter safe $ words opts
	where
		safe o
			-- Don't allow user to pass --delete to rsync;
			-- that could cause it to delete other keys
			-- in the same hash bucket as a key it sends.
			| o == "--delete" = False
			| o == "--delete-excluded" = False
			| otherwise = True

rsyncSetup :: UUID -> RemoteConfig -> Annex RemoteConfig
rsyncSetup u c = do
	-- verify configuration is sane
	let url = fromMaybe (error "Specify rsyncurl=") $
		M.lookup "rsyncurl" c
	c' <- encryptionSetup c

	-- The rsyncurl is stored in git config, not only in this remote's
	-- persistant state, so it can vary between hosts.
	gitConfigSpecialRemote u c' "rsyncurl" url
	return c'

rsyncKey :: RsyncOpts -> Key -> String
rsyncKey o k = rsyncUrl o </> hashDirMixed k </> shellEscape (f </> f)
        where
                f = keyFile k

rsyncKeyDir :: RsyncOpts -> Key -> String
rsyncKeyDir o k = rsyncUrl o </> hashDirMixed k </> shellEscape (keyFile k)

store :: RsyncOpts -> Key -> Annex Bool
store o k = do
	g <- gitRepo
	rsyncSend o k (gitAnnexLocation g k)

storeEncrypted :: RsyncOpts -> (Cipher, Key) -> Key -> Annex Bool
storeEncrypted o (cipher, enck) k = withTmp enck $ \tmp -> do
	g <- gitRepo
	let f = gitAnnexLocation g k
	liftIO $ withEncryptedContent cipher (L.readFile f) $ \s -> L.writeFile tmp s
	rsyncSend o enck tmp

retrieve :: RsyncOpts -> Key -> FilePath -> Annex Bool
retrieve o k f = rsyncRemote o
	-- use inplace when retrieving to support resuming
	[ Param "--inplace"
	, Param $ rsyncKey o k
	, Param f
	]

retrieveEncrypted :: RsyncOpts -> (Cipher, Key) -> FilePath -> Annex Bool
retrieveEncrypted o (cipher, enck) f = withTmp enck $ \tmp -> do
	res <- retrieve o enck tmp
	if res
		then liftIO $ catchBool $ do
			withDecryptedContent cipher (L.readFile tmp) $ L.writeFile f
			return True
		else return res

remove :: RsyncOpts -> Key -> Annex Bool
remove o k = withRsyncScratchDir $ \tmp -> do
	{- Send an empty directory to rysnc as the parent directory
         - of the file to remove. -}
	let dummy = tmp </> keyFile k
	liftIO $ createDirectoryIfMissing True dummy
	liftIO $ rsync $ rsyncOptions o ++
		[ Params "--delete --recursive"
		, partialParams
		, Param $ addTrailingPathSeparator dummy
		, Param $ rsyncKeyDir o k
		]

checkPresent :: Git.Repo -> RsyncOpts -> Key -> Annex (Either IOException Bool)
checkPresent r o k = do
	showAction $ "checking " ++ Git.repoDescribe r
	-- note: Does not currently differnetiate between rsync failing
	-- to connect, and the file not being present.
	res <- liftIO $ boolSystem "sh" [Param "-c", Param cmd]
	return $ Right res
	where
		cmd = "rsync --quiet " ++ shellEscape (rsyncKey o k) ++ " 2>/dev/null"

{- Rsync params to enable resumes of sending files safely,
 - ensure that files are only moved into place once complete
 -}
partialParams :: CommandParam
partialParams = Params "--no-inplace --partial --partial-dir=.rsync-partial"

{- Runs an action in an empty scratch directory that can be used to build
 - up trees for rsync. -}
withRsyncScratchDir :: (FilePath -> Annex Bool) -> Annex Bool
withRsyncScratchDir a = do
	g <- gitRepo
	pid <- liftIO getProcessID
	let tmp = gitAnnexTmpDir g </> "rsynctmp" </> show pid
	nuke tmp
	liftIO $ createDirectoryIfMissing True tmp
	res <- a tmp
	nuke tmp
	return res
	where
		nuke d = liftIO $ 
			doesDirectoryExist d >>? removeDirectoryRecursive d

rsyncRemote :: RsyncOpts -> [CommandParam] -> Annex Bool
rsyncRemote o params = do
	showOutput -- make way for progress bar
	res <- liftIO $ rsync $ rsyncOptions o ++ defaultParams ++ params
	if res
		then return res
		else do
			showLongNote "rsync failed -- run git annex again to resume file transfer"
			return res
	where
		defaultParams = [Params "--progress"]

{- To send a single key is slightly tricky; need to build up a temporary
   directory structure to pass to rsync so it can create the hash
   directories. -}
rsyncSend :: RsyncOpts -> Key -> FilePath -> Annex Bool
rsyncSend o k src = withRsyncScratchDir $ \tmp -> do
	let dest = tmp </> hashDirMixed k </> f </> f
	liftIO $ createDirectoryIfMissing True $ parentDir dest
	liftIO $ createLink src dest
	rsyncRemote o
		[ Param "--recursive"
		, partialParams
 		  -- tmp/ to send contents of tmp dir
		, Param $ addTrailingPathSeparator tmp
		, Param $ rsyncUrl o
		]
	where
		f = keyFile k