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
196
197
198
199
200
201
202
203
|
{- git-annex assistant pending transfer queue
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Assistant.TransferQueue (
TransferQueue,
Schedule(..),
newTransferQueue,
getTransferQueue,
queueTransfers,
queueTransfersMatching,
queueDeferredDownloads,
queueTransfer,
queueTransferAt,
queueTransferWhenSmall,
getNextTransfer,
getMatchingTransfers,
dequeueTransfers,
) where
import Assistant.Common
import Assistant.DaemonStatus
import Assistant.Types.TransferQueue
import Logs.Transfer
import Types.Remote
import qualified Remote
import qualified Types.Remote as Remote
import Annex.Wanted
import Control.Concurrent.STM
import qualified Data.Map as M
{- Reads the queue's content without blocking or changing it. -}
getTransferQueue :: Assistant [(Transfer, TransferInfo)]
getTransferQueue = (atomically . readTVar . queuelist) <<~ transferQueue
stubInfo :: AssociatedFile -> Remote -> TransferInfo
stubInfo f r = stubTransferInfo
{ transferRemote = Just r
, associatedFile = f
}
{- Adds transfers to queue for some of the known remotes.
- Honors preferred content settings, only transferring wanted files. -}
queueTransfers :: Schedule -> Key -> AssociatedFile -> Direction -> Assistant ()
queueTransfers = queueTransfersMatching (const True)
{- Adds transfers to queue for some of the known remotes, that match a
- condition. Honors preferred content settings. -}
queueTransfersMatching :: (UUID -> Bool) -> Schedule -> Key -> AssociatedFile -> Direction -> Assistant ()
queueTransfersMatching matching schedule k f direction
| direction == Download = whenM (liftAnnex $ wantGet f) go
| otherwise = go
where
go = do
rs <- liftAnnex . sufficientremotes
=<< syncRemotes <$> getDaemonStatus
let matchingrs = filter (matching . Remote.uuid) rs
if null matchingrs
then defer
else forM_ matchingrs $ \r ->
enqueue schedule (gentransfer r) (stubInfo f r)
sufficientremotes rs
{- Queue downloads from all remotes that
- have the key, with the cheapest ones first.
- More expensive ones will only be tried if
- downloading from a cheap one fails. -}
| direction == Download = do
uuids <- Remote.keyLocations k
return $ filter (\r -> uuid r `elem` uuids) rs
{- Upload to all remotes that want the content. -}
| otherwise = filterM (wantSend f . Remote.uuid) $
filter (not . Remote.readonly) rs
gentransfer r = Transfer
{ transferDirection = direction
, transferKey = k
, transferUUID = Remote.uuid r
}
defer
{- Defer this download, as no known remote has the key. -}
| direction == Download = do
q <- getAssistant transferQueue
void $ liftIO $ atomically $
modifyTVar' (deferreddownloads q) $
\l -> (k, f):l
| otherwise = noop
{- Queues any deferred downloads that can now be accomplished, leaving
- any others in the list to try again later. -}
queueDeferredDownloads :: Schedule -> Assistant ()
queueDeferredDownloads schedule = do
q <- getAssistant transferQueue
l <- liftIO $ atomically $ swapTVar (deferreddownloads q) []
rs <- syncRemotes <$> getDaemonStatus
left <- filterM (queue rs) l
unless (null left) $
liftIO $ atomically $ modifyTVar' (deferreddownloads q) $
\new -> new ++ left
where
queue rs (k, f) = do
uuids <- liftAnnex $ Remote.keyLocations k
let sources = filter (\r -> uuid r `elem` uuids) rs
unless (null sources) $
forM_ sources $ \r ->
enqueue schedule (gentransfer r) (stubInfo f r)
return $ null sources
where
gentransfer r = Transfer
{ transferDirection = Download
, transferKey = k
, transferUUID = Remote.uuid r
}
enqueue :: Schedule -> Transfer -> TransferInfo -> Assistant ()
enqueue schedule t info
| schedule == Next = go (new:)
| otherwise = go (\l -> l++[new])
where
new = (t, info)
go modlist = do
q <- getAssistant transferQueue
liftIO $ atomically $ do
void $ modifyTVar' (queuesize q) succ
void $ modifyTVar' (queuelist q) modlist
notifyTransfer
{- Adds a transfer to the queue. -}
queueTransfer :: Schedule -> AssociatedFile -> Transfer -> Remote -> Assistant ()
queueTransfer schedule f t remote = enqueue schedule t (stubInfo f remote)
{- Blocks until the queue is no larger than a given size, and then adds a
- transfer to the queue. -}
queueTransferAt :: Int -> Schedule -> AssociatedFile -> Transfer -> Remote -> Assistant ()
queueTransferAt wantsz schedule f t remote = do
q <- getAssistant transferQueue
liftIO $ atomically $ do
sz <- readTVar (queuesize q)
unless (sz <= wantsz) $
retry -- blocks until queuesize changes
enqueue schedule t (stubInfo f remote)
queueTransferWhenSmall :: AssociatedFile -> Transfer -> Remote -> Assistant ()
queueTransferWhenSmall = queueTransferAt 10 Later
{- Blocks until a pending transfer is available in the queue,
- and removes it.
-
- Checks that it's acceptable, before adding it to the
- the currentTransfers map. If it's not acceptable, it's discarded.
-
- This is done in a single STM transaction, so there is no window
- where an observer sees an inconsistent status. -}
getNextTransfer :: (TransferInfo -> Bool) -> Assistant (Maybe (Transfer, TransferInfo))
getNextTransfer acceptable = do
q <- getAssistant transferQueue
dstatus <- getAssistant daemonStatusHandle
liftIO $ atomically $ do
sz <- readTVar (queuesize q)
if sz < 1
then retry -- blocks until queuesize changes
else do
(r@(t,info):rest) <- readTVar (queuelist q)
writeTVar (queuelist q) rest
void $ modifyTVar' (queuesize q) pred
if acceptable info
then do
adjustTransfersSTM dstatus $
M.insertWith' const t info
return $ Just r
else return Nothing
{- Moves transfers matching a condition from the queue, to the
- currentTransfers map. -}
getMatchingTransfers :: (Transfer -> Bool) -> Assistant [(Transfer, TransferInfo)]
getMatchingTransfers c = do
q <- getAssistant transferQueue
dstatus <- getAssistant daemonStatusHandle
liftIO $ atomically $ do
ts <- dequeueTransfersSTM q c
unless (null ts) $
adjustTransfersSTM dstatus $ \m -> M.union m $ M.fromList ts
return ts
{- Removes transfers matching a condition from the queue, and returns the
- removed transfers. -}
dequeueTransfers :: (Transfer -> Bool) -> Assistant [(Transfer, TransferInfo)]
dequeueTransfers c = do
q <- getAssistant transferQueue
removed <- liftIO $ atomically $ dequeueTransfersSTM q c
unless (null removed) $
notifyTransfer
return removed
dequeueTransfersSTM :: TransferQueue -> (Transfer -> Bool) -> STM [(Transfer, TransferInfo)]
dequeueTransfersSTM q c = do
(removed, ts) <- partition (c . fst)
<$> readTVar (queuelist q)
void $ writeTVar (queuesize q) (length ts)
void $ writeTVar (queuelist q) ts
return removed
|
