1 {-| Implementation of the iallocator interface.
7 Copyright (C) 2009 Google Inc.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful, but
15 WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
26 module Ganeti.HTools.IAlloc
33 import Text.JSON (JSObject, JSValue(JSBool, JSString, JSArray),
34 makeObj, encodeStrict, decodeStrict,
35 fromJSObject, toJSString)
36 import qualified Ganeti.HTools.Container as Container
37 import qualified Ganeti.HTools.Node as Node
38 import qualified Ganeti.HTools.Instance as Instance
39 import Ganeti.HTools.Loader
40 import Ganeti.HTools.Utils
41 import Ganeti.HTools.Types
43 -- | Parse the basic specifications of an instance.
45 -- Instances in the cluster instance list and the instance in an
46 -- 'Allocate' request share some common properties, which are read by
48 parseBaseInstance :: String
49 -> [(String, JSValue)]
50 -> Result (String, Instance.Instance)
51 parseBaseInstance n a = do
52 disk <- fromObj "disk_space_total" a
53 mem <- fromObj "memory" a
54 vcpus <- fromObj "vcpus" a
55 tags <- fromObj "tags" a
56 let running = "running"
57 return (n, Instance.create n mem disk vcpus running tags 0 0)
59 -- | Parses an instance as found in the cluster instance listg.
60 parseInstance :: NameAssoc -- ^ The node name-to-index association list
61 -> String -- ^ The name of the instance
62 -> [(String, JSValue)] -- ^ The JSON object
63 -> Result (String, Instance.Instance)
64 parseInstance ktn n a = do
65 base <- parseBaseInstance n a
66 nodes <- fromObj "nodes" a
67 pnode <- if null nodes
68 then Bad $ "empty node list for instance " ++ n
69 else readEitherString $ head nodes
70 pidx <- lookupNode ktn n pnode
71 let snodes = tail nodes
72 sidx <- (if null snodes then return Node.noSecondary
73 else readEitherString (head snodes) >>= lookupNode ktn n)
74 return (n, Instance.setBoth (snd base) pidx sidx)
76 -- | Parses a node as found in the cluster node list.
77 parseNode :: String -- ^ The node's name
78 -> [(String, JSValue)] -- ^ The JSON object
79 -> Result (String, Node.Node)
81 offline <- fromObj "offline" a
82 drained <- fromObj "drained" a
83 node <- (if offline || drained
84 then return $ Node.create n 0 0 0 0 0 0 True
86 mtotal <- fromObj "total_memory" a
87 mnode <- fromObj "reserved_memory" a
88 mfree <- fromObj "free_memory" a
89 dtotal <- fromObj "total_disk" a
90 dfree <- fromObj "free_disk" a
91 ctotal <- fromObj "total_cpus" a
92 return $ Node.create n mtotal mnode mfree
93 dtotal dfree ctotal False)
96 -- | Top-level parser.
97 parseData :: String -- ^ The JSON message as received from Ganeti
98 -> Result Request -- ^ A (possible valid) request
100 decoded <- fromJResult $ decodeStrict body
101 let obj = fromJSObject decoded
103 request <- liftM fromJSObject (fromObj "request" obj)
104 -- existing node parsing
105 nlist <- liftM fromJSObject (fromObj "nodes" obj)
106 nobj <- mapM (\(x,y) -> asJSObject y >>= parseNode x . fromJSObject) nlist
107 let (ktn, nl) = assignIndices nobj
108 -- existing instance parsing
109 ilist <- fromObj "instances" obj
110 let idata = fromJSObject ilist
111 iobj <- mapM (\(x,y) ->
112 asJSObject y >>= parseInstance ktn x . fromJSObject) idata
113 let (kti, il) = assignIndices iobj
115 ctags <- fromObj "cluster_tags" obj
116 (map_n, map_i, ptags, csf) <- mergeData [] [] (nl, il, ctags)
117 optype <- fromObj "type" request
122 rname <- fromObj "name" request
123 req_nodes <- fromObj "required_nodes" request
124 inew <- parseBaseInstance rname request
126 return $ Allocate io req_nodes
129 rname <- fromObj "name" request
130 ridx <- lookupInstance kti rname
131 req_nodes <- fromObj "required_nodes" request
132 ex_nodes <- fromObj "relocate_from" request
133 let ex_nodes' = map (stripSuffix $ length csf) ex_nodes
134 ex_idex <- mapM (Container.findByName map_n) ex_nodes'
135 return $ Relocate ridx req_nodes (map Node.idx ex_idex)
138 ex_names <- fromObj "evac_nodes" request
139 let ex_names' = map (stripSuffix $ length csf) ex_names
140 ex_nodes <- mapM (Container.findByName map_n) ex_names'
141 let ex_ndx = map Node.idx ex_nodes
142 return $ Evacuate ex_ndx
143 other -> fail ("Invalid request type '" ++ other ++ "'")
144 return $ Request rqtype map_n map_i ptags csf
146 -- | Format the result
147 formatRVal :: String -> RqType -> [Node.AllocElement] -> JSValue
148 formatRVal _ _ [] = JSArray []
150 formatRVal csf (Evacuate _) elems =
151 let sols = map (\(_, inst, nl) ->
152 let names = Instance.name inst : map Node.name nl
153 in map (++ csf) names) elems
154 jsols = map (JSArray . map (JSString . toJSString)) sols
157 formatRVal csf _ elems =
158 let (_, _, nodes) = head elems
159 nodes' = map ((++ csf) . Node.name) nodes
160 in JSArray $ map (JSString . toJSString) nodes'
162 -- | Formats the response into a valid IAllocator response message.
163 formatResponse :: Bool -- ^ Whether the request was successful
164 -> String -- ^ Information text
165 -> String -- ^ Suffix for nodes/instances
166 -> RqType -- ^ Request type
167 -> [Node.AllocElement] -- ^ The resulting allocations
168 -> String -- ^ The JSON-formatted message
169 formatResponse success info csf rq elems =
171 e_success = ("success", JSBool success)
172 e_info = ("info", JSString . toJSString $ info)
173 e_nodes = ("nodes", formatRVal csf rq elems)
174 in encodeStrict $ makeObj [e_success, e_info, e_nodes]