diff --git a/Makefile.am b/Makefile.am
index 75c83f6844a2345181a3a966a976295f828fb0f4..ba36d2b3e434841f3123e2560d44be160ead8968 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -426,6 +426,7 @@ HS_LIB_SRCS = \
htools/Ganeti/Confd/Utils.hs \
htools/Ganeti/Config.hs \
htools/Ganeti/Daemon.hs \
+ htools/Ganeti/Errors.hs \
htools/Ganeti/HTools/CLI.hs \
htools/Ganeti/HTools/Cluster.hs \
htools/Ganeti/HTools/Container.hs \
@@ -475,6 +476,7 @@ HS_TEST_SRCS = \
htest/Test/Ganeti/Common.hs \
htest/Test/Ganeti/Confd/Utils.hs \
htest/Test/Ganeti/Daemon.hs \
+ htest/Test/Ganeti/Errors.hs \
htest/Test/Ganeti/HTools/CLI.hs \
htest/Test/Ganeti/HTools/Cluster.hs \
htest/Test/Ganeti/HTools/Container.hs \
diff --git a/htest/Test/Ganeti/Errors.hs b/htest/Test/Ganeti/Errors.hs
new file mode 100644
index 0000000000000000000000000000000000000000..3bf7cac231ec78a7bce35fe21ad6f98f765bf5bb
--- /dev/null
+++ b/htest/Test/Ganeti/Errors.hs
@@ -0,0 +1,48 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+{-| Unittests for "Ganeti.Errors".
+
+-}
+
+{-
+
+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 Test.Ganeti.Errors (testErrors) where
+
+import Test.QuickCheck
+
+import Test.Ganeti.TestHelper
+import Test.Ganeti.TestCommon
+
+import qualified Ganeti.Errors as Errors
+
+$(genArbitrary ''Errors.ErrorCode)
+
+$(genArbitrary ''Errors.GanetiException)
+
+-- | Tests error serialisation.
+prop_GenericError_serialisation :: Errors.GanetiException -> Property
+prop_GenericError_serialisation = testSerialisation
+
+testSuite "Errors"
+ [ 'prop_GenericError_serialisation
+ ]
diff --git a/htest/test.hs b/htest/test.hs
index 9100095562eaabe91fb93d8ff67e7350607eb306..e5849a086c8ba3536e2d29b2e2ab933d8d6af9b9 100644
--- a/htest/test.hs
+++ b/htest/test.hs
@@ -34,6 +34,7 @@ import Test.Ganeti.BasicTypes
import Test.Ganeti.Confd.Utils
import Test.Ganeti.Common
import Test.Ganeti.Daemon
+import Test.Ganeti.Errors
import Test.Ganeti.HTools.CLI
import Test.Ganeti.HTools.Cluster
import Test.Ganeti.HTools.Container
@@ -75,6 +76,7 @@ allTests =
, testCommon
, testConfd_Utils
, testDaemon
+ , testErrors
, testHTools_CLI
, testHTools_Cluster
, testHTools_Container
diff --git a/htools/Ganeti/Errors.hs b/htools/Ganeti/Errors.hs
new file mode 100644
index 0000000000000000000000000000000000000000..74ffa21ea536354ba232016041d510e7086e617f
--- /dev/null
+++ b/htools/Ganeti/Errors.hs
@@ -0,0 +1,117 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+{-| Implementation of the Ganeti error types.
+
+This module implements our error hierarchy. Currently we implement one
+identical to the Python one; later we might one to have separate ones
+for frontend (clients), master and backend code.
+
+-}
+
+{-
+
+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.Errors
+ ( ErrorCode(..)
+ , GanetiException(..)
+ , ErrorResult
+ , excName
+ ) where
+
+import Text.JSON hiding (Result, Ok)
+
+import Ganeti.THH
+import Ganeti.BasicTypes
+import qualified Ganeti.Constants as C
+
+-- | Error code types for 'OpPrereqError'.
+$(declareSADT "ErrorCode"
+ [ ("ECodeResolver", 'C.errorsEcodeResolver)
+ , ("ECodeNoRes", 'C.errorsEcodeNores)
+ , ("ECodeInval", 'C.errorsEcodeInval)
+ , ("ECodeState", 'C.errorsEcodeState)
+ , ("ECodeNoEnt", 'C.errorsEcodeNoent)
+ , ("ECodeExists", 'C.errorsEcodeExists)
+ , ("ECodeNotUnique", 'C.errorsEcodeNotunique)
+ , ("ECodeFault", 'C.errorsEcodeFault)
+ , ("ECodeEnviron", 'C.errorsEcodeEnviron)
+ ])
+$(makeJSONInstance ''ErrorCode)
+
+$(genException "GanetiException"
+ [ ("GenericError", [excErrMsg])
+ , ("LockError", [excErrMsg])
+ , ("PidFileLockError", [excErrMsg])
+ , ("HypervisorError", [excErrMsg])
+ , ("ProgrammerError", [excErrMsg])
+ , ("BlockDeviceError", [excErrMsg])
+ , ("ConfigurationError", [excErrMsg])
+ , ("ConfigVersionMismatch", [ ("expCode", [t| Int |])
+ , ("actCode", [t| Int |])])
+ , ("ReservationError", [excErrMsg])
+ , ("RemoteError", [excErrMsg])
+ , ("SignatureError", [excErrMsg])
+ , ("ParameterError", [excErrMsg])
+ , ("ResultValidationError", [excErrMsg])
+ , ("OpPrereqError", [excErrMsg, ("errCode", [t| ErrorCode |])])
+ , ("OpExecError", [excErrMsg])
+ , ("OpResultError", [excErrMsg])
+ , ("OpCodeUnknown", [excErrMsg])
+ , ("JobLost", [excErrMsg])
+ , ("JobFileCorrupted", [excErrMsg])
+ , ("ResolverError", [ ("errHostname", [t| String |])
+ , ("errResolverCode", [t| Int |])
+ , ("errResolverMsg", [t| String |])])
+ , ("HooksFailure", [excErrMsg])
+ , ("HooksAbort", [("errs", [t| [(String, String, String)] |])])
+ , ("UnitParseError", [excErrMsg])
+ , ("ParseError", [excErrMsg])
+ , ("TypeEnforcementError", [excErrMsg])
+ , ("X509CertError", [excErrMsg])
+ , ("TagError", [excErrMsg])
+ , ("CommandError", [excErrMsg])
+ , ("StorageError", [excErrMsg])
+ , ("InotifyError", [excErrMsg])
+ , ("JobQueueError", [excErrMsg])
+ , ("JobQueueDrainError", [excErrMsg])
+ , ("JobQueueFull", [])
+ , ("ConfdMagicError", [excErrMsg])
+ , ("ConfdClientError", [excErrMsg])
+ , ("UdpDataSizeError", [excErrMsg])
+ , ("NoCtypesError", [excErrMsg])
+ , ("IPAddressError", [excErrMsg])
+ , ("LuxiError", [excErrMsg])
+ , ("QueryFilterParseError", [excErrMsg]) -- not consistent with Python
+ , ("RapiTestResult", [excErrMsg])
+ , ("FileStoragePathError", [excErrMsg])
+ ])
+
+instance JSON GanetiException where
+ showJSON = saveGanetiException
+ readJSON = loadGanetiException
+
+instance FromString GanetiException where
+ mkFromString = GenericError
+
+-- | Error monad using 'GanetiException' type alias.
+type ErrorResult = GenericResult GanetiException
+
+$(genStrOfOp ''GanetiException "excName")
diff --git a/htools/Ganeti/THH.hs b/htools/Ganeti/THH.hs
index 643684650cd91b76ddc30aed5049b68d1d3da3ea..bf9802eabe0669d3b89fb6e80c98852d10665266 100644
--- a/htools/Ganeti/THH.hs
+++ b/htools/Ganeti/THH.hs
@@ -53,6 +53,8 @@ module Ganeti.THH ( declareSADT
, buildObjectSerialisation
, buildParam
, DictObject(..)
+ , genException
+ , excErrMsg
) where
import Control.Monad (liftM)
@@ -63,6 +65,7 @@ import qualified Data.Set as Set
import Language.Haskell.TH
import qualified Text.JSON as JSON
+import Text.JSON.Pretty (pp_value)
-- * Exported types
@@ -881,3 +884,108 @@ fillParam sname field_pfx fields = do
(NormalB $ LetE (le_full:le_part:le_new) obj_new) []
fun = FunD fun_name [fclause]
return [sig, fun]
+
+-- * Template code for exceptions
+
+-- | Exception simple error message field.
+excErrMsg :: (String, Q Type)
+excErrMsg = ("errMsg", [t| String |])
+
+-- | Builds an exception type definition.
+genException :: String -- ^ Name of new type
+ -> SimpleObject -- ^ Constructor name and parameters
+ -> Q [Dec]
+genException name cons = do
+ let tname = mkName name
+ declD <- buildSimpleCons tname cons
+ (savesig, savefn) <- genSaveSimpleObj tname ("save" ++ name) cons $
+ uncurry saveExcCons
+ (loadsig, loadfn) <- genLoadExc tname ("load" ++ name) cons
+ return [declD, loadsig, loadfn, savesig, savefn]
+
+-- | Generates the \"save\" clause for an entire exception constructor.
+--
+-- This matches the exception with variables named the same as the
+-- constructor fields (just so that the spliced in code looks nicer),
+-- and calls showJSON on it.
+saveExcCons :: String -- ^ The constructor name
+ -> [SimpleField] -- ^ The parameter definitions for this
+ -- constructor
+ -> Q Clause -- ^ Resulting clause
+saveExcCons sname fields = do
+ let cname = mkName sname
+ fnames <- mapM (newName . fst) fields
+ let pat = conP cname (map varP fnames)
+ felems = if null fnames
+ then conE '() -- otherwise, empty list has no type
+ else listE $ map (\f -> [| JSON.showJSON $(varE f) |]) fnames
+ let tup = tupE [ litE (stringL sname), felems ]
+ clause [pat] (normalB [| JSON.showJSON $tup |]) []
+
+-- | Generates load code for a single constructor of an exception.
+--
+-- Generates the code (if there's only one argument, we will use a
+-- list, not a tuple:
+--
+-- @
+-- do
+-- (x1, x2, ...) <- readJSON args
+-- return $ Cons x1 x2 ...
+-- @
+loadExcConstructor :: Name -> String -> [SimpleField] -> Q Exp
+loadExcConstructor inname sname fields = do
+ let name = mkName sname
+ f_names <- mapM (newName . fst) fields
+ let read_args = AppE (VarE 'JSON.readJSON) (VarE inname)
+ let binds = case f_names of
+ [x] -> BindS (ListP [VarP x])
+ _ -> BindS (TupP (map VarP f_names))
+ cval = foldl (\accu fn -> AppE accu (VarE fn)) (ConE name) f_names
+ return $ DoE [binds read_args, NoBindS (AppE (VarE 'return) cval)]
+
+{-| Generates the loadException function.
+
+This generates a quite complicated function, along the lines of:
+
+@
+loadFn (JSArray [JSString name, args]) = case name of
+ "A1" -> do
+ (x1, x2, ...) <- readJSON args
+ return $ A1 x1 x2 ...
+ "a2" -> ...
+ s -> fail $ "Unknown exception" ++ s
+loadFn v = fail $ "Expected array but got " ++ show v
+@
+-}
+genLoadExc :: Name -> String -> SimpleObject -> Q (Dec, Dec)
+genLoadExc tname sname opdefs = do
+ let fname = mkName sname
+ exc_name <- newName "name"
+ exc_args <- newName "args"
+ exc_else <- newName "s"
+ arg_else <- newName "v"
+ fails <- [| fail $ "Unknown exception '" ++ $(varE exc_else) ++ "'" |]
+ -- default match for unknown exception name
+ let defmatch = Match (VarP exc_else) (NormalB fails) []
+ -- the match results (per-constructor blocks)
+ str_matches <-
+ mapM (\(s, params) -> do
+ body_exp <- loadExcConstructor exc_args s params
+ return $ Match (LitP (StringL s)) (NormalB body_exp) [])
+ opdefs
+ -- the first function clause; we can't use [| |] due to TH
+ -- limitations, so we have to build the AST by hand
+ let clause1 = Clause [ConP 'JSON.JSArray
+ [ListP [ConP 'JSON.JSString [VarP exc_name],
+ VarP exc_args]]]
+ (NormalB (CaseE (AppE (VarE 'JSON.fromJSString)
+ (VarE exc_name))
+ (str_matches ++ [defmatch]))) []
+ -- the fail expression for the second function clause
+ fail_type <- [| fail $ "Invalid exception: expected '(string, [args])' " ++
+ " but got " ++ show (pp_value $(varE arg_else)) ++ "'"
+ |]
+ -- the second function clause
+ let clause2 = Clause [VarP arg_else] (NormalB fail_type) []
+ sigt <- [t| JSON.JSValue -> JSON.Result $(conT tname) |]
+ return $ (SigD fname sigt, FunD fname [clause1, clause2])