1 {-# LANGUAGE TemplateHaskell #-}
3 {-| Implementation of the Ganeti LUXI interface.
9 Copyright (C) 2009, 2010, 2011, 2012 Google Inc.
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 2 of the License, or
14 (at your option) any later version.
16 This program is distributed in the hope that it will be useful, but
17 WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
53 import Control.Exception (catch)
55 import Data.Ratio (numerator, denominator)
56 import qualified Data.ByteString as B
57 import qualified Data.ByteString.UTF8 as UTF8
58 import Data.Word (Word8)
60 import Text.JSON (encodeStrict, decodeStrict)
61 import qualified Text.JSON as J
62 import Text.JSON.Pretty (pp_value)
63 import Text.JSON.Types
64 import System.Directory (removeFile)
65 import System.IO (hClose, hFlush, hWaitForInput, Handle, IOMode(..))
66 import System.IO.Error (isEOFError)
68 import qualified Network.Socket as S
70 import Ganeti.BasicTypes
71 import Ganeti.Constants
74 import Ganeti.Jobs (JobStatus)
77 import qualified Ganeti.Query.Language as Qlang
80 -- * Utility functions
82 -- | Wrapper over System.Timeout.timeout that fails in the IO monad.
83 withTimeout :: Int -> String -> IO a -> IO a
84 withTimeout secs descr action = do
85 result <- timeout (secs * 1000000) action
87 Nothing -> fail $ "Timeout in " ++ descr
90 -- * Generic protocol functionality
92 -- | Result of receiving a message from the socket.
93 data RecvResult = RecvConnClosed -- ^ Connection closed
94 | RecvError String -- ^ Any other error
95 | RecvOk String -- ^ Successfull receive
96 deriving (Show, Read, Eq)
98 -- | The Ganeti job type.
101 -- | Currently supported Luxi operations and JSON serialization.
104 [ simpleField "what" [t| Qlang.ItemType |]
105 , simpleField "fields" [t| [String] |]
106 , simpleField "qfilter" [t| Qlang.Filter Qlang.FilterField |]
108 , (luxiReqQueryFields,
109 [ simpleField "what" [t| Qlang.ItemType |]
110 , simpleField "fields" [t| [String] |]
112 , (luxiReqQueryNodes,
113 [ simpleField "names" [t| [String] |]
114 , simpleField "fields" [t| [String] |]
115 , simpleField "lock" [t| Bool |]
117 , (luxiReqQueryGroups,
118 [ simpleField "names" [t| [String] |]
119 , simpleField "fields" [t| [String] |]
120 , simpleField "lock" [t| Bool |]
122 , (luxiReqQueryInstances,
123 [ simpleField "names" [t| [String] |]
124 , simpleField "fields" [t| [String] |]
125 , simpleField "lock" [t| Bool |]
128 [ simpleField "ids" [t| [Int] |]
129 , simpleField "fields" [t| [String] |]
131 , (luxiReqQueryExports,
132 [ simpleField "nodes" [t| [String] |]
133 , simpleField "lock" [t| Bool |]
135 , (luxiReqQueryConfigValues,
136 [ simpleField "fields" [t| [String] |] ]
138 , (luxiReqQueryClusterInfo, [])
140 [ simpleField "kind" [t| TagObject |]
141 , simpleField "name" [t| String |]
144 [ simpleField "job" [t| [OpCode] |] ]
146 , (luxiReqSubmitManyJobs,
147 [ simpleField "ops" [t| [[OpCode]] |] ]
149 , (luxiReqWaitForJobChange,
150 [ simpleField "job" [t| Int |]
151 , simpleField "fields" [t| [String]|]
152 , simpleField "prev_job" [t| JSValue |]
153 , simpleField "prev_log" [t| JSValue |]
154 , simpleField "tmout" [t| Int |]
156 , (luxiReqArchiveJob,
157 [ simpleField "job" [t| Int |] ]
159 , (luxiReqAutoArchiveJobs,
160 [ simpleField "age" [t| Int |]
161 , simpleField "tmout" [t| Int |]
164 [ simpleField "job" [t| Int |] ]
166 , (luxiReqSetDrainFlag,
167 [ simpleField "flag" [t| Bool |] ]
169 , (luxiReqSetWatcherPause,
170 [ simpleField "duration" [t| Double |] ]
174 $(makeJSONInstance ''LuxiReq)
176 -- | List of all defined Luxi calls.
177 $(genAllConstr (drop 3) ''LuxiReq "allLuxiCalls")
179 -- | The serialisation of LuxiOps into strings in messages.
180 $(genStrOfOp ''LuxiOp "strOfOp")
182 -- | Type holding the initial (unparsed) Luxi call.
183 data LuxiCall = LuxiCall LuxiReq JSValue
185 -- | The end-of-message separator.
189 -- | The end-of-message encoded as a ByteString.
191 bEOM = B.singleton eOM
193 -- | Valid keys in the requests and responses.
194 data MsgKeys = Method
199 -- | The serialisation of MsgKeys into strings in messages.
200 $(genStrOfKey ''MsgKeys "strOfKey")
202 -- | Luxi client encapsulation.
203 data Client = Client { socket :: Handle -- ^ The socket of the client
204 , rbuf :: IORef B.ByteString -- ^ Already received buffer
207 -- | Connects to the master daemon and returns a luxi Client.
208 getClient :: String -> IO Client
210 s <- S.socket S.AF_UNIX S.Stream S.defaultProtocol
211 withTimeout luxiDefCtmo "creating luxi connection" $
212 S.connect s (S.SockAddrUnix path)
213 rf <- newIORef B.empty
214 h <- S.socketToHandle s ReadWriteMode
215 return Client { socket=h, rbuf=rf }
217 -- | Creates and returns a server endpoint.
218 getServer :: FilePath -> IO S.Socket
220 s <- S.socket S.AF_UNIX S.Stream S.defaultProtocol
221 S.bindSocket s (S.SockAddrUnix path)
222 S.listen s 5 -- 5 is the max backlog
225 -- | Closes a server endpoint.
226 -- FIXME: this should be encapsulated into a nicer type.
227 closeServer :: FilePath -> S.Socket -> IO ()
228 closeServer path sock = do
232 -- | Accepts a client
233 acceptClient :: S.Socket -> IO Client
235 -- second return is the address of the client, which we ignore here
236 (client_socket, _) <- S.accept s
237 new_buffer <- newIORef B.empty
238 handle <- S.socketToHandle client_socket ReadWriteMode
239 return Client { socket=handle, rbuf=new_buffer }
241 -- | Closes the client socket.
242 closeClient :: Client -> IO ()
243 closeClient = hClose . socket
245 -- | Sends a message over a luxi transport.
246 sendMsg :: Client -> String -> IO ()
247 sendMsg s buf = withTimeout luxiDefRwto "sending luxi message" $ do
248 let encoded = UTF8.fromString buf
250 B.hPut handle encoded
254 -- | Given a current buffer and the handle, it will read from the
255 -- network until we get a full message, and it will return that
256 -- message and the leftover buffer contents.
257 recvUpdate :: Handle -> B.ByteString -> IO (B.ByteString, B.ByteString)
258 recvUpdate handle obuf = do
259 nbuf <- withTimeout luxiDefRwto "reading luxi response" $ do
260 _ <- hWaitForInput handle (-1)
261 B.hGetNonBlocking handle 4096
262 let (msg, remaining) = B.break (eOM ==) nbuf
263 newbuf = B.append obuf msg
265 then recvUpdate handle newbuf
266 else return (newbuf, B.tail remaining)
268 -- | Waits for a message over a luxi transport.
269 recvMsg :: Client -> IO String
271 cbuf <- readIORef $ rbuf s
272 let (imsg, ibuf) = B.break (eOM ==) cbuf
274 if B.null ibuf -- if old buffer didn't contain a full message
275 then recvUpdate (socket s) cbuf -- then we read from network
276 else return (imsg, B.tail ibuf) -- else we return data from our buffer
277 writeIORef (rbuf s) nbuf
278 return $ UTF8.toString msg
280 -- | Extended wrapper over recvMsg.
281 recvMsgExt :: Client -> IO RecvResult
283 Control.Exception.catch (liftM RecvOk (recvMsg s)) $ \e ->
284 return $ if isEOFError e
286 else RecvError (show e)
288 -- | Serialize a request to String.
289 buildCall :: LuxiOp -- ^ The method
290 -> String -- ^ The serialized form
292 let ja = [ (strOfKey Method, J.showJSON $ strOfOp lo)
293 , (strOfKey Args, opToArgs lo)
298 -- | Serialize the response to String.
299 buildResponse :: Bool -- ^ Success
300 -> JSValue -- ^ The arguments
301 -> String -- ^ The serialized form
302 buildResponse success args =
303 let ja = [ (strOfKey Success, JSBool success)
304 , (strOfKey Result, args)]
308 -- | Check that luxi request contains the required keys and parse it.
309 validateCall :: String -> Result LuxiCall
311 arr <- fromJResult "parsing top-level luxi message" $
312 decodeStrict s::Result (JSObject JSValue)
313 let aobj = fromJSObject arr
314 call <- fromObj aobj (strOfKey Method)::Result LuxiReq
315 args <- fromObj aobj (strOfKey Args)
316 return (LuxiCall call args)
318 -- | Converts Luxi call arguments into a 'LuxiOp' data structure.
320 -- This is currently hand-coded until we make it more uniform so that
321 -- it can be generated using TH.
322 decodeCall :: LuxiCall -> Result LuxiOp
323 decodeCall (LuxiCall call args) =
326 (jid, jargs) <- fromJVal args
327 rid <- mapM parseJobId jid
328 let rargs = map fromJSString jargs
329 return $ QueryJobs rid rargs
330 ReqQueryInstances -> do
331 (names, fields, locking) <- fromJVal args
332 return $ QueryInstances names fields locking
334 (names, fields, locking) <- fromJVal args
335 return $ QueryNodes names fields locking
337 (names, fields, locking) <- fromJVal args
338 return $ QueryGroups names fields locking
339 ReqQueryClusterInfo ->
340 return QueryClusterInfo
342 (what, fields, qfilter) <- fromJVal args
343 return $ Query what fields qfilter
345 (what, fields) <- fromJVal args
346 fields' <- case fields of
349 return $ QueryFields what fields'
351 [ops1] <- fromJVal args
352 ops2 <- mapM (fromJResult (luxiReqToRaw call) . J.readJSON) ops1
353 return $ SubmitJob ops2
354 ReqSubmitManyJobs -> do
355 [ops1] <- fromJVal args
356 ops2 <- mapM (fromJResult (luxiReqToRaw call) . J.readJSON) ops1
357 return $ SubmitManyJobs ops2
358 ReqWaitForJobChange -> do
359 (jid, fields, pinfo, pidx, wtmout) <-
360 -- No instance for 5-tuple, code copied from the
361 -- json sources and adapted
362 fromJResult "Parsing WaitForJobChange message" $
364 JSArray [a, b, c, d, e] ->
371 _ -> J.Error "Not enough values"
372 rid <- parseJobId jid
373 return $ WaitForJobChange rid fields pinfo pidx wtmout
375 [jid] <- fromJVal args
376 rid <- parseJobId jid
377 return $ ArchiveJob rid
378 ReqAutoArchiveJobs -> do
379 (age, tmout) <- fromJVal args
380 return $ AutoArchiveJobs age tmout
381 ReqQueryExports -> do
382 (nodes, lock) <- fromJVal args
383 return $ QueryExports nodes lock
384 ReqQueryConfigValues -> do
385 [fields] <- fromJVal args
386 return $ QueryConfigValues fields
388 (kind, name) <- fromJVal args
389 return $ QueryTags kind name
391 [job] <- fromJVal args
392 rid <- parseJobId job
393 return $ CancelJob rid
394 ReqSetDrainFlag -> do
395 [flag] <- fromJVal args
396 return $ SetDrainFlag flag
397 ReqSetWatcherPause -> do
398 [duration] <- fromJVal args
399 return $ SetWatcherPause duration
401 -- | Check that luxi responses contain the required keys and that the
402 -- call was successful.
403 validateResult :: String -> ErrorResult JSValue
404 validateResult s = do
405 when (UTF8.replacement_char `elem` s) $
406 fail "Failed to decode UTF-8, detected replacement char after decoding"
407 oarr <- fromJResult "Parsing LUXI response" (decodeStrict s)
408 let arr = J.fromJSObject oarr
409 status <- fromObj arr (strOfKey Success)
410 result <- fromObj arr (strOfKey Result)
413 else decodeError result
415 -- | Try to decode an error from the server response. This function
416 -- will always fail, since it's called only on the error path (when
418 decodeError :: JSValue -> ErrorResult JSValue
422 Bad msg -> Bad $ GenericError msg
424 -- | Generic luxi method call.
425 callMethod :: LuxiOp -> Client -> IO (ErrorResult JSValue)
426 callMethod method s = do
427 sendMsg s $ buildCall method
429 let rval = validateResult result
432 -- | Parses a job ID.
433 parseJobId :: JSValue -> Result JobId
434 parseJobId (JSString x) = tryRead "parsing job id" . fromJSString $ x
435 parseJobId (JSRational _ x) =
436 if denominator x /= 1
437 then Bad $ "Got fractional job ID from master daemon?! Value:" ++ show x
438 -- FIXME: potential integer overflow here on 32-bit platforms
439 else Ok . fromIntegral . numerator $ x
440 parseJobId x = Bad $ "Wrong type/value for job id: " ++ show x
442 -- | Parse job submission result.
443 parseSubmitJobResult :: JSValue -> ErrorResult JobId
444 parseSubmitJobResult (JSArray [JSBool True, v]) =
446 Bad msg -> Bad $ LuxiError msg
448 parseSubmitJobResult (JSArray [JSBool False, JSString x]) =
449 Bad . LuxiError $ fromJSString x
450 parseSubmitJobResult v =
451 Bad . LuxiError $ "Unknown result from the master daemon: " ++
454 -- | Specialized submitManyJobs call.
455 submitManyJobs :: Client -> [[OpCode]] -> IO (ErrorResult [JobId])
456 submitManyJobs s jobs = do
457 rval <- callMethod (SubmitManyJobs jobs) s
458 -- map each result (status, payload) pair into a nice Result ADT
459 return $ case rval of
461 Ok (JSArray r) -> mapM parseSubmitJobResult r
462 x -> Bad . LuxiError $
463 "Cannot parse response from Ganeti: " ++ show x
465 -- | Custom queryJobs call.
466 queryJobsStatus :: Client -> [JobId] -> IO (ErrorResult [JobStatus])
467 queryJobsStatus s jids = do
468 rval <- callMethod (QueryJobs jids ["status"]) s
469 return $ case rval of
471 Ok y -> case J.readJSON y::(J.Result [[JobStatus]]) of
472 J.Ok vals -> if any null vals
474 LuxiError "Missing job status field"
475 else Ok (map head vals)
476 J.Error x -> Bad $ LuxiError x