Rpc.hs 11.7 KB
Newer Older
1
{-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies, CPP,
2
  BangPatterns, TemplateHaskell #-}
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

{-| Implementation of the RPC client.

-}

{-

Copyright (C) 2012 Google Inc.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.

-}

module Ganeti.Rpc
  ( RpcCall
  , RpcResult
  , Rpc
  , RpcError(..)
34
  , ERpcError
35
  , executeRpcCall
36
37
38
39
40
41
42

  , rpcCallName
  , rpcCallTimeout
  , rpcCallData
  , rpcCallAcceptOffline

  , rpcResultFill
43
44
45
46
47

  , InstanceInfo(..)
  , RpcCallAllInstancesInfo(..)
  , RpcResultAllInstancesInfo(..)

48
49
50
  , RpcCallInstanceList(..)
  , RpcResultInstanceList(..)

51
52
53
54
55
  , HvInfo(..)
  , VgInfo(..)
  , RpcCallNodeInfo(..)
  , RpcResultNodeInfo(..)

Agata Murawska's avatar
Agata Murawska committed
56
57
58
  , RpcCallVersion(..)
  , RpcResultVersion(..)

59
  , rpcTimeoutFromRaw -- FIXME: Not used anywhere
60
61
  ) where

62
import Control.Arrow (second)
63
import qualified Text.JSON as J
64
import Text.JSON.Pretty (pp_value)
65
import Text.JSON (makeObj)
66

67
68
#ifndef NO_CURL
import Network.Curl
Agata Murawska's avatar
Agata Murawska committed
69
import qualified Ganeti.Path as P
70
71
72
#endif

import qualified Ganeti.Constants as C
73
import Ganeti.Objects
74
import Ganeti.THH
75
76
import Ganeti.Compat
import Ganeti.JSON
77
78
79
80
81

#ifndef NO_CURL
-- | The curl options used for RPC.
curlOpts :: [CurlOption]
curlOpts = [ CurlFollowLocation False
Agata Murawska's avatar
Agata Murawska committed
82
           , CurlCAInfo P.nodedCertFile
83
84
85
           , CurlSSLVerifyHost 0
           , CurlSSLVerifyPeer True
           , CurlSSLCertType "PEM"
Agata Murawska's avatar
Agata Murawska committed
86
           , CurlSSLCert P.nodedCertFile
87
           , CurlSSLKeyType "PEM"
Agata Murawska's avatar
Agata Murawska committed
88
           , CurlSSLKey P.nodedCertFile
89
90
91
           , CurlConnectTimeout (fromIntegral C.rpcConnectTimeout)
           ]
#endif
92
93
94
95
96
97

-- | Data type for RPC error reporting.
data RpcError
  = CurlDisabledError
  | CurlLayerError Node String
  | JsonDecodeError String
Agata Murawska's avatar
Agata Murawska committed
98
  | RpcResultError String
99
100
101
102
103
104
105
  | OfflineNodeError Node
  deriving Eq

instance Show RpcError where
  show CurlDisabledError =
    "RPC/curl backend disabled at compile time"
  show (CurlLayerError node code) =
Agata Murawska's avatar
Agata Murawska committed
106
    "Curl error for " ++ nodeName node ++ ", " ++ code
107
  show (JsonDecodeError msg) =
Agata Murawska's avatar
Agata Murawska committed
108
109
110
    "Error while decoding JSON from HTTP response: " ++ msg
  show (RpcResultError msg) =
    "Error reponse received from RPC server: " ++ msg
111
112
113
  show (OfflineNodeError node) =
    "Node " ++ nodeName node ++ " is marked as offline"

114
115
type ERpcError = Either RpcError

116
117
118
119
120
121
122
123
124
125
-- | Basic timeouts for RPC calls.
$(declareIADT "RpcTimeout"
  [ ( "Urgent",    'C.rpcTmoUrgent )
  , ( "Fast",      'C.rpcTmoFast )
  , ( "Normal",    'C.rpcTmoNormal )
  , ( "Slow",      'C.rpcTmoSlow )
  , ( "FourHours", 'C.rpcTmo4hrs )
  , ( "OneDay",    'C.rpcTmo1day )
  ])

126
127
128
129
130
131
132
133
134
135
136
137
138
139
-- | A generic class for RPC calls.
class (J.JSON a) => RpcCall a where
  -- | Give the (Python) name of the procedure.
  rpcCallName :: a -> String
  -- | Calculate the timeout value for the call execution.
  rpcCallTimeout :: a -> Int
  -- | Prepare arguments of the call to be send as POST.
  rpcCallData :: Node -> a -> String
  -- | Whether we accept offline nodes when making a call.
  rpcCallAcceptOffline :: a -> Bool

-- | A generic class for RPC results with default implementation.
class (J.JSON a) => RpcResult a where
  -- | Create a result based on the received HTTP response.
140
  rpcResultFill :: (Monad m) => J.JSValue -> m (ERpcError a)
141
142
143
144

-- | Generic class that ensures matching RPC call with its respective
-- result.
class (RpcCall a, RpcResult b) => Rpc a b | a -> b
145
146
147
148
149
150
151
152
153
154

-- | Http Request definition.
data HttpClientRequest = HttpClientRequest
  { requestTimeout :: Int
  , requestUrl :: String
  , requestPostData :: String
  }

-- | Execute the request and return the result as a plain String. When
-- curl reports an error, we propagate it.
155
156
executeHttpRequest :: Node -> ERpcError HttpClientRequest
                   -> IO (ERpcError String)
157
158
159
160
161
162
163
164
165
166
167
168

executeHttpRequest _ (Left rpc_err) = return $ Left rpc_err
#ifdef NO_CURL
executeHttpRequest _ _ = return $ Left CurlDisabledError
#else
executeHttpRequest node (Right request) = do
  let reqOpts = [ CurlTimeout (fromIntegral $ requestTimeout request)
                , CurlPostFields [requestPostData request]
                ]
      url = requestUrl request
  -- FIXME: This is very similar to getUrl in Htools/Rapi.hs
  (code, !body) <- curlGetString url $ curlOpts ++ reqOpts
Iustin Pop's avatar
Iustin Pop committed
169
170
171
  return $ case code of
             CurlOK -> Right body
             _ -> Left $ CurlLayerError node (show code)
172
173
174
175
176
177
178
#endif

-- | Prepare url for the HTTP request.
prepareUrl :: (RpcCall a) => Node -> a -> String
prepareUrl node call =
  let node_ip = nodePrimaryIp node
      port = snd C.daemonsPortsGanetiNoded
Iustin Pop's avatar
Iustin Pop committed
179
180
      path_prefix = "https://" ++ node_ip ++ ":" ++ show port
  in path_prefix ++ "/" ++ rpcCallName call
181
182
183
184

-- | Create HTTP request for a given node provided it is online,
-- otherwise create empty response.
prepareHttpRequest ::  (RpcCall a) => Node -> a
185
                   -> ERpcError HttpClientRequest
186
prepareHttpRequest node call
Iustin Pop's avatar
Iustin Pop committed
187
188
189
190
191
  | rpcCallAcceptOffline call || not (nodeOffline node) =
      Right HttpClientRequest { requestTimeout = rpcCallTimeout call
                              , requestUrl = prepareUrl node call
                              , requestPostData = rpcCallData node call
                              }
192
193
  | otherwise = Left $ OfflineNodeError node

194
195
196
197
198
199
200
201
202
203
204
-- | Parse a result based on the received HTTP response.
rpcResultParse :: (Monad m, RpcResult a) => String -> m (ERpcError a)
rpcResultParse res = do
  res' <- fromJResult "Reading JSON response" $ J.decode res
  case res' of
    (True, res'') ->
       rpcResultFill res''
    (False, jerr) -> case jerr of
       J.JSString msg -> return . Left $ RpcResultError (J.fromJSString msg)
       _ -> (return . Left) . JsonDecodeError $ show (pp_value jerr)

205
-- | Parse the response or propagate the error.
206
207
parseHttpResponse :: (Monad m, RpcResult a) => ERpcError String
                  -> m (ERpcError a)
208
parseHttpResponse (Left err) = return $ Left err
209
parseHttpResponse (Right response) = rpcResultParse response
210
211

-- | Execute RPC call for a sigle node.
212
executeSingleRpcCall :: (Rpc a b) => Node -> a -> IO (Node, ERpcError b)
213
214
215
216
217
218
219
executeSingleRpcCall node call = do
  let request = prepareHttpRequest node call
  response <- executeHttpRequest node request
  result <- parseHttpResponse response
  return (node, result)

-- | Execute RPC call for many nodes in parallel.
220
executeRpcCall :: (Rpc a b) => [Node] -> a -> IO [(Node, ERpcError b)]
221
222
223
executeRpcCall nodes call =
  sequence $ parMap rwhnf (uncurry executeSingleRpcCall)
               (zip nodes $ repeat call)
224

225
226
227
228
229
230
231
232
233
-- | Helper function that is used to read dictionaries of values.
sanitizeDictResults :: [(String, J.Result a)] -> ERpcError [(String, a)]
sanitizeDictResults [] = Right []
sanitizeDictResults ((_, J.Error err):_) = Left $ JsonDecodeError err
sanitizeDictResults ((name, J.Ok val):xs) =
  case sanitizeDictResults xs of
    Left err -> Left err
    Right res' -> Right $ (name, val):res'

234
235
236
-- * RPC calls and results

-- | AllInstancesInfo
237
--   Returns information about all running instances on the given nodes.
Iustin Pop's avatar
Iustin Pop committed
238
$(buildObject "RpcCallAllInstancesInfo" "rpcCallAllInstInfo"
239
240
  [ simpleField "hypervisors" [t| [Hypervisor] |] ])

Iustin Pop's avatar
Iustin Pop committed
241
$(buildObject "InstanceInfo" "instInfo"
242
243
  [ simpleField "memory" [t| Int|]
  , simpleField "state"  [t| String |] -- It depends on hypervisor :(
244
245
246
247
  , simpleField "vcpus"  [t| Int |]
  , simpleField "time"   [t| Int |]
  ])

Iustin Pop's avatar
Iustin Pop committed
248
$(buildObject "RpcResultAllInstancesInfo" "rpcResAllInstInfo"
249
  [ simpleField "instances" [t| [(String, InstanceInfo)] |] ])
250
251
252
253
254

instance RpcCall RpcCallAllInstancesInfo where
  rpcCallName _ = "all_instances_info"
  rpcCallTimeout _ = rpcTimeoutToRaw Urgent
  rpcCallAcceptOffline _ = False
255
256
257
258
259
260
261
262
263
264
265
266
267
268
  rpcCallData _ call = J.encode [rpcCallAllInstInfoHypervisors call]

instance RpcResult RpcResultAllInstancesInfo where
  -- FIXME: Is there a simpler way to do it?
  rpcResultFill res =
    return $ case res of
      J.JSObject res' -> do
        let res'' = map (second J.readJSON) (J.fromJSObject res')
                        :: [(String, J.Result InstanceInfo)]
        case sanitizeDictResults res'' of
          Left err -> Left err
          Right insts -> Right $ RpcResultAllInstancesInfo insts
      _ -> Left $ JsonDecodeError
           ("Expected JSObject, got " ++ show res)
269
270

instance Rpc RpcCallAllInstancesInfo RpcResultAllInstancesInfo
271
272
273

-- | InstanceList
-- Returns the list of running instances on the given nodes.
Iustin Pop's avatar
Iustin Pop committed
274
$(buildObject "RpcCallInstanceList" "rpcCallInstList"
275
276
  [ simpleField "hypervisors" [t| [Hypervisor] |] ])

Iustin Pop's avatar
Iustin Pop committed
277
$(buildObject "RpcResultInstanceList" "rpcResInstList"
278
  [ simpleField "instances" [t| [String] |] ])
279
280
281
282
283

instance RpcCall RpcCallInstanceList where
  rpcCallName _ = "instance_list"
  rpcCallTimeout _ = rpcTimeoutToRaw Urgent
  rpcCallAcceptOffline _ = False
284
  rpcCallData _ call = J.encode [rpcCallInstListHypervisors call]
285

286
287
288
289
290
instance RpcResult RpcResultInstanceList where
  rpcResultFill res =
    return $ case J.readJSON res of
      J.Error err -> Left $ JsonDecodeError err
      J.Ok insts -> Right $ RpcResultInstanceList insts
291
292

instance Rpc RpcCallInstanceList RpcResultInstanceList
293
294
295

-- | NodeInfo
-- Return node information.
Iustin Pop's avatar
Iustin Pop committed
296
$(buildObject "RpcCallNodeInfo" "rpcCallNodeInfo"
297
298
  [ simpleField "volume_groups" [t| [String] |]
  , simpleField "hypervisors" [t| [Hypervisor] |]
299
300
  ])

Iustin Pop's avatar
Iustin Pop committed
301
$(buildObject "VgInfo" "vgInfo"
302
  [ simpleField "name" [t| String |]
303
304
  , optionalField $ simpleField "vg_free" [t| Int |]
  , optionalField $ simpleField "vg_size" [t| Int |]
305
306
307
  ])

-- | We only provide common fields as described in hv_base.py.
Iustin Pop's avatar
Iustin Pop committed
308
$(buildObject "HvInfo" "hvInfo"
309
310
311
312
313
314
315
316
  [ simpleField "memory_total" [t| Int |]
  , simpleField "memory_free" [t| Int |]
  , simpleField "memory_dom0" [t| Int |]
  , simpleField "cpu_total" [t| Int |]
  , simpleField "cpu_nodes" [t| Int |]
  , simpleField "cpu_sockets" [t| Int |]
  ])

Iustin Pop's avatar
Iustin Pop committed
317
$(buildObject "RpcResultNodeInfo" "rpcResNodeInfo"
318
319
320
321
322
323
324
325
326
  [ simpleField "boot_id" [t| String |]
  , simpleField "vg_info" [t| [VgInfo] |]
  , simpleField "hv_info" [t| [HvInfo] |]
  ])

instance RpcCall RpcCallNodeInfo where
  rpcCallName _ = "node_info"
  rpcCallTimeout _ = rpcTimeoutToRaw Urgent
  rpcCallAcceptOffline _ = False
327
328
329
330
331
332
333
334
335
336
  rpcCallData _ call = J.encode ( rpcCallNodeInfoVolumeGroups call
                                , rpcCallNodeInfoHypervisors call
                                )

instance RpcResult RpcResultNodeInfo where
  rpcResultFill res =
    return $ case J.readJSON res of
      J.Error err -> Left $ JsonDecodeError err
      J.Ok (boot_id, vg_info, hv_info) ->
          Right $ RpcResultNodeInfo boot_id vg_info hv_info
337
338

instance Rpc RpcCallNodeInfo RpcResultNodeInfo
Agata Murawska's avatar
Agata Murawska committed
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367

-- | Version
-- Query node version.
-- Note: We can't use THH as it does not know what to do with empty dict
data RpcCallVersion = RpcCallVersion {}
  deriving (Show, Read, Eq)

instance J.JSON RpcCallVersion where
  showJSON _ = J.JSNull
  readJSON J.JSNull = return RpcCallVersion
  readJSON _ = fail "Unable to read RpcCallVersion"

$(buildObject "RpcResultVersion" "rpcResultVersion"
  [ simpleField "version" [t| Int |]
  ])

instance RpcCall RpcCallVersion where
  rpcCallName _ = "version"
  rpcCallTimeout _ = rpcTimeoutToRaw Urgent
  rpcCallAcceptOffline _ = True
  rpcCallData call _ = J.encode [call]

instance RpcResult RpcResultVersion where
  rpcResultFill res =
    return $ case J.readJSON res of
      J.Error err -> Left $ JsonDecodeError err
      J.Ok ver -> Right $ RpcResultVersion ver

instance Rpc RpcCallVersion RpcResultVersion