Rpc.hs 9 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
  , executeRpcCall
35
36
37
38
39
40
41

  , rpcCallName
  , rpcCallTimeout
  , rpcCallData
  , rpcCallAcceptOffline

  , rpcResultFill
42
43
44
45
46

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

47
48
49
  , RpcCallInstanceList(..)
  , RpcResultInstanceList(..)

50
51
52
53
54
  , HvInfo(..)
  , VgInfo(..)
  , RpcCallNodeInfo(..)
  , RpcResultNodeInfo(..)

55
  , rpcTimeoutFromRaw -- FIXME: Not used anywhere
56
57
58
  ) where

import qualified Text.JSON as J
59
import Text.JSON (makeObj)
60

61
62
63
64
65
#ifndef NO_CURL
import Network.Curl
#endif

import qualified Ganeti.Constants as C
66
import Ganeti.Objects
67
import Ganeti.THH
68
import Ganeti.HTools.Compat
69
import Ganeti.HTools.JSON
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84

#ifndef NO_CURL
-- | The curl options used for RPC.
curlOpts :: [CurlOption]
curlOpts = [ CurlFollowLocation False
           , CurlCAInfo C.nodedCertFile
           , CurlSSLVerifyHost 0
           , CurlSSLVerifyPeer True
           , CurlSSLCertType "PEM"
           , CurlSSLCert C.nodedCertFile
           , CurlSSLKeyType "PEM"
           , CurlSSLKey C.nodedCertFile
           , CurlConnectTimeout (fromIntegral C.rpcConnectTimeout)
           ]
#endif
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104

-- | Data type for RPC error reporting.
data RpcError
  = CurlDisabledError
  | CurlLayerError Node String
  | JsonDecodeError String
  | OfflineNodeError Node
  deriving Eq

instance Show RpcError where
  show CurlDisabledError =
    "RPC/curl backend disabled at compile time"
  show (CurlLayerError node code) =
    "Curl error for " ++ nodeName node ++ ", error " ++ code
  show (JsonDecodeError msg) =
    "Error while decoding JSON from HTTP response " ++ msg
  show (OfflineNodeError node) =
    "Node " ++ nodeName node ++ " is marked as offline"

rpcErrorJsonReport :: (Monad m) => J.Result a -> m (Either RpcError a)
Iustin Pop's avatar
Iustin Pop committed
105
rpcErrorJsonReport (J.Error x) = return . Left $ JsonDecodeError x
106
107
rpcErrorJsonReport (J.Ok x) = return $ Right x

108
109
110
111
112
113
114
115
116
117
-- | 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 )
  ])

118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
-- | 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

  rpcCallData _ = J.encode

-- | 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.
  rpcResultFill :: (Monad m) => String -> m (Either RpcError a)

  rpcResultFill res = rpcErrorJsonReport $  J.decode res

-- | Generic class that ensures matching RPC call with its respective
-- result.
class (RpcCall a, RpcResult b) => Rpc a b | a -> b
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164

-- | 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.
executeHttpRequest :: Node -> Either RpcError HttpClientRequest
                   -> IO (Either RpcError String)

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
165
166
167
  return $ case code of
             CurlOK -> Right body
             _ -> Left $ CurlLayerError node (show code)
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
204
205
206
207
208
209
#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
      path_prefix = "https://" ++ (node_ip) ++ ":" ++ (show port) in
  path_prefix ++ "/" ++ rpcCallName call

-- | Create HTTP request for a given node provided it is online,
-- otherwise create empty response.
prepareHttpRequest ::  (RpcCall a) => Node -> a
                   -> Either RpcError HttpClientRequest
prepareHttpRequest node call
  | rpcCallAcceptOffline call ||
    (not $ nodeOffline node) =
      Right $ HttpClientRequest { requestTimeout = rpcCallTimeout call
                                , requestUrl = prepareUrl node call
                                , requestPostData = rpcCallData node call
                                }
  | otherwise = Left $ OfflineNodeError node

-- | Parse the response or propagate the error.
parseHttpResponse :: (Monad m, RpcResult a) => Either RpcError String
                  -> m (Either RpcError a)
parseHttpResponse (Left err) = return $ Left err
parseHttpResponse (Right response) = rpcResultFill response

-- | Execute RPC call for a sigle node.
executeSingleRpcCall :: (Rpc a b) => Node -> a -> IO (Node, Either RpcError b)
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.
executeRpcCall :: (Rpc a b) => [Node] -> a -> IO [(Node, Either RpcError b)]
executeRpcCall nodes call =
  sequence $ parMap rwhnf (uncurry executeSingleRpcCall)
               (zip nodes $ repeat call)
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236

-- * RPC calls and results

-- | AllInstancesInfo
--   Returns information about all instances on the given nodes
$(buildObject "RpcCallAllInstancesInfo" "rpcCallAllInstInfo" $
  [ simpleField "hypervisors" [t| [Hypervisor] |] ])

$(buildObject "InstanceInfo" "instInfo" $
  [ simpleField "name"   [t| String |]
  , simpleField "memory" [t| Int|]
  , simpleField "state"  [t| AdminState |]
  , simpleField "vcpus"  [t| Int |]
  , simpleField "time"   [t| Int |]
  ])

$(buildObject "RpcResultAllInstancesInfo" "rpcResAllInstInfo" $
  [ simpleField "instances" [t| [InstanceInfo] |] ])

instance RpcCall RpcCallAllInstancesInfo where
  rpcCallName _ = "all_instances_info"
  rpcCallTimeout _ = rpcTimeoutToRaw Urgent
  rpcCallAcceptOffline _ = False

instance RpcResult RpcResultAllInstancesInfo

instance Rpc RpcCallAllInstancesInfo RpcResultAllInstancesInfo
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255

-- | InstanceList
-- Returns the list of running instances on the given nodes.
$(buildObject "RpcCallInstanceList" "rpcCallInstList" $
  [ simpleField "hypervisors" [t| [Hypervisor] |] ])

$(buildObject "RpcResultInstanceList" "rpcResInstList" $
  [ simpleField "node"      [t| Node |]
  , simpleField "instances" [t| [String] |]
  ])

instance RpcCall RpcCallInstanceList where
  rpcCallName _ = "instance_list"
  rpcCallTimeout _ = rpcTimeoutToRaw Urgent
  rpcCallAcceptOffline _ = False

instance RpcResult RpcResultInstanceList

instance Rpc RpcCallInstanceList RpcResultInstanceList
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293

-- | NodeInfo
-- Return node information.
$(buildObject "RpcCallNodeInfo" "rpcCallNodeInfo" $
  [ simpleField "hypervisors" [t| [Hypervisor] |]
  , simpleField "volume_groups" [t| [String] |]
  ])

$(buildObject "VgInfo" "vgInfo" $
  [ simpleField "name" [t| String |]
  , simpleField "free" [t| Int |]
  , simpleField "size" [t| Int |]
  ])

-- | We only provide common fields as described in hv_base.py.
$(buildObject "HvInfo" "hvInfo" $
  [ 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 |]
  ])

$(buildObject "RpcResultNodeInfo" "rpcResNodeInfo" $
  [ 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

instance RpcResult RpcResultNodeInfo

instance Rpc RpcCallNodeInfo RpcResultNodeInfo