{-
-Copyright (C) 2011 Google Inc.
+Copyright (C) 2011, 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
, defaultField
, optionalField
, renameField
- , containerField
, customField
, timeStampFields
, uuidFields
, serialFields
+ , tagsFields
, buildObject
, buildObjectSerialisation
, buildParam
- , Container
) where
-import Control.Arrow
-import Control.Monad (liftM, liftM2)
+import Control.Monad (liftM)
import Data.Char
import Data.List
-import qualified Data.Map as M
+import qualified Data.Set as Set
import Language.Haskell.TH
import qualified Text.JSON as JSON
-import Ganeti.HTools.JSON
-
-- * Exported types
-type Container = M.Map String
-
-- | Serialised field data type.
data Field = Field { fieldName :: String
, fieldType :: Q Type
, fieldShow :: Maybe (Q Exp)
, fieldDefault :: Maybe (Q Exp)
, fieldConstr :: Maybe String
- , fieldIsContainer :: Bool
, fieldIsOptional :: Bool
}
, fieldShow = Nothing
, fieldDefault = Nothing
, fieldConstr = Nothing
- , fieldIsContainer = False
, fieldIsOptional = False
}
optionalField :: Field -> Field
optionalField field = field { fieldIsOptional = True }
--- | Marks a field as a container.
-containerField :: Field -> Field
-containerField field = field { fieldIsContainer = True }
-
-- | Sets custom functions on a field.
-customField :: Q Exp -> Q Exp -> Field -> Field
+customField :: Name -- ^ The name of the read function
+ -> Name -- ^ The name of the show function
+ -> Field -- ^ The original field
+ -> Field -- ^ Updated field
customField readfn showfn field =
- field { fieldRead = Just readfn, fieldShow = Just showfn }
+ field { fieldRead = Just (varE readfn), fieldShow = Just (varE showfn) }
fieldRecordName :: Field -> String
fieldRecordName (Field { fieldName = name, fieldConstr = alias }) =
fieldVariable f =
case (fieldConstr f) of
Just name -> ensureLower name
- _ -> fieldName f
+ _ -> map (\c -> if c == '-' then '_' else c) $ fieldName f
actualFieldType :: Field -> Q Type
-actualFieldType f | fieldIsContainer f = [t| Container $t |]
- | fieldIsOptional f = [t| Maybe $t |]
+actualFieldType f | fieldIsOptional f = [t| Maybe $t |]
| otherwise = t
where t = fieldType f
fail $ "Default field " ++ name ++ " used in parameter declaration"
checkNonOptDef _ = return ()
-loadFn :: Field -> Q Exp -> Q Exp
-loadFn (Field { fieldIsContainer = True }) expr = [| $expr >>= readContainer |]
-loadFn (Field { fieldRead = Just readfn }) expr = [| $expr >>= $readfn |]
-loadFn _ expr = expr
-
-saveFn :: Field -> Q Exp -> Q Exp
-saveFn (Field { fieldIsContainer = True }) expr = [| showContainer $expr |]
-saveFn (Field { fieldRead = Just readfn }) expr = [| $readfn $expr |]
-saveFn _ expr = expr
+-- | Produces the expression that will de-serialise a given
+-- field. Since some custom parsing functions might need to use the
+-- entire object, we do take and pass the object to any custom read
+-- functions.
+loadFn :: Field -- ^ The field definition
+ -> Q Exp -- ^ The value of the field as existing in the JSON message
+ -> Q Exp -- ^ The entire object in JSON object format
+ -> Q Exp -- ^ Resulting expression
+loadFn (Field { fieldRead = Just readfn }) expr o = [| $expr >>= $readfn $o |]
+loadFn _ expr _ = expr
-- * Common field declarations
uuidFields :: [Field]
uuidFields = [ simpleField "uuid" [t| String |] ]
+-- | Tag field description.
+tagsFields :: [Field]
+tagsFields = [ defaultField [| Set.empty |] $
+ simpleField "tags" [t| Set.Set String |] ]
+
-- * Helper functions
-- | Ensure first letter is lowercase.
appFn f x | f == VarE 'id = x
| otherwise = AppE f x
--- | Container loader
-readContainer :: (Monad m, JSON.JSON a) =>
- JSON.JSObject JSON.JSValue -> m (Container a)
-readContainer obj = do
- let kjvlist = JSON.fromJSObject obj
- kalist <- mapM (\(k, v) -> fromKeyValue k v >>= \a -> return (k, a)) kjvlist
- return $ M.fromList kalist
-
--- | Container dumper
-showContainer :: (JSON.JSON a) => Container a -> JSON.JSValue
-showContainer = JSON.makeObj . map (second JSON.showJSON) . M.toList
-
-- * Template code for simple raw type-equivalent ADTs
-- | Generates a data type declaration.
-- @
genToRaw :: Name -> Name -> Name -> [(String, Either String Name)] -> Q [Dec]
genToRaw traw fname tname constructors = do
- sigt <- [t| $(conT tname) -> $(conT traw) |]
+ let sigt = AppT (AppT ArrowT (ConT tname)) (ConT traw)
-- the body clauses, matching on the constructor and returning the
-- raw value
clauses <- mapM (\(c, v) -> clause [recP (mkName c) []]
-- @
--
-- in an instance JSON /name/ declaration
-genShowJSON :: String -> Q [Dec]
-genShowJSON name = [d| showJSON = JSON.showJSON . $(varE (toRawName name)) |]
+genShowJSON :: String -> Q Dec
+genShowJSON name = do
+ body <- [| JSON.showJSON . $(varE (toRawName name)) |]
+ return $ FunD (mkName "showJSON") [Clause [] (NormalB body) []]
-- | Creates the readJSON member of a JSON instance declaration.
--
let base = nameBase name
showJ <- genShowJSON base
readJ <- genReadJSON base
- return [InstanceD [] (AppT (ConT ''JSON.JSON) (ConT name)) (readJ:showJ)]
+ return [InstanceD [] (AppT (ConT ''JSON.JSON) (ConT name)) [readJ,showJ]]
-- * Template code for opcodes
-- | Transform an underscore_name into a CamelCase one.
camelCase :: String -> String
camelCase = concatMap (ensureUpper . drop 1) .
- groupBy (\_ b -> b /= '_') . ('_':)
+ groupBy (\_ b -> b /= '_' && b /= '-') . ('_':)
-- | Computes the name of a given constructor.
constructorName :: Con -> Q Name
constructorName (RecC name _) = return name
constructorName x = fail $ "Unhandled constructor " ++ show x
+-- | Extract all constructor names from a given type.
+reifyConsNames :: Name -> Q [String]
+reifyConsNames name = do
+ reify_result <- reify name
+ case reify_result of
+ TyConI (DataD _ _ _ cons _) -> mapM (liftM nameBase . constructorName) cons
+ o -> fail $ "Unhandled name passed to reifyConsNames, expected\
+ \ type constructor but got '" ++ show o ++ "'"
+
-- | Builds the generic constructor-to-string function.
--
-- This generates a simple function of the following form:
-- 'genToRaw' to actually generate the function
genConstrToStr :: (String -> String) -> Name -> String -> Q [Dec]
genConstrToStr trans_fun name fname = do
- TyConI (DataD _ _ _ cons _) <- reify name
- cnames <- mapM (liftM nameBase . constructorName) cons
+ cnames <- reifyConsNames name
let svalues = map (Left . trans_fun) cnames
genToRaw ''String (mkName fname) name $ zip cnames svalues
-> Q Clause -- ^ Resulting clause
saveConstructor sname fields = do
let cname = mkName sname
- let fnames = map (mkName . fieldVariable) fields
+ fnames <- mapM (newName . fieldVariable) fields
let pat = conP cname (map varP fnames)
let felems = map (uncurry saveObjectField) (zip fnames fields)
-- now build the OP_ID serialisation
genStrOfKey = genConstrToStr ensureLower
-- | LuxiOp parameter type.
-type LuxiParam = (String, Q Type, Q Exp)
+type LuxiParam = (String, Q Type)
-- | Generates the LuxiOp data type.
--
-- We can't use anything less generic, because the way different
-- operations are serialized differs on both parameter- and top-level.
--
--- There are three things to be defined for each parameter:
+-- There are two things to be defined for each parameter:
--
-- * name
--
-- * type
--
--- * operation; this is the operation performed on the parameter before
--- serialization
---
genLuxiOp :: String -> [(String, [LuxiParam])] -> Q [Dec]
genLuxiOp name cons = do
decl_d <- mapM (\(cname, fields) -> do
- fields' <- mapM (\(_, qt, _) ->
+ fields' <- mapM (\(_, qt) ->
qt >>= \t -> return (NotStrict, t))
fields
return $ NormalC (mkName cname) fields')
cons
- let declD = DataD [] (mkName name) [] decl_d [''Show, ''Read]
+ let declD = DataD [] (mkName name) [] decl_d [''Show, ''Read, ''Eq]
(savesig, savefn) <- genSaveLuxiOp cons
- return [declD, savesig, savefn]
+ req_defs <- declareSADT "LuxiReq" .
+ map (\(str, _) -> ("Req" ++ str, mkName ("luxiReq" ++ str))) $
+ cons
+ return $ [declD, savesig, savefn] ++ req_defs
-- | Generates the \"save\" expression for a single luxi parameter.
saveLuxiField :: Name -> LuxiParam -> Q Exp
-saveLuxiField fvar (_, qt, fn) =
- [| JSON.showJSON ( $(liftM2 appFn fn $ varE fvar) ) |]
+saveLuxiField fvar (_, qt) =
+ [| JSON.showJSON $(varE fvar) |]
-- | Generates the \"save\" clause for entire LuxiOp constructor.
saveLuxiConstructor :: (String, [LuxiParam]) -> Q Clause
saveLuxiConstructor (sname, fields) = do
let cname = mkName sname
- fnames = map (\(nm, _, _) -> mkName nm) fields
+ fnames = map (mkName . fst) fields
pat = conP cname (map varP fnames)
flist = map (uncurry saveLuxiField) (zip fnames fields)
finval = if null flist
shjson <- objectShowJSON sname
rdjson <- objectReadJSON sname
let instdecl = InstanceD [] (AppT (ConT ''JSON.JSON) (ConT name))
- (rdjson:shjson)
+ [rdjson, shjson]
return $ savedecls ++ [loadsig, loadfn, instdecl]
genSaveObject :: (Name -> Field -> Q Exp)
-> String -> [Field] -> Q [Dec]
genSaveObject save_fn sname fields = do
let name = mkName sname
- let fnames = map (mkName . fieldVariable) fields
+ fnames <- mapM (newName . fieldVariable) fields
let pat = conP name (map varP fnames)
let tdname = mkName ("toDict" ++ sname)
tdsigt <- [t| $(conT name) -> [(String, JSON.JSValue)] |]
saveObjectField :: Name -> Field -> Q Exp
saveObjectField fvar field
- | isContainer = [| [( $nameE , JSON.showJSON . showContainer $ $fvarE)] |]
| fisOptional = [| case $(varE fvar) of
Nothing -> []
Just v -> [( $nameE, JSON.showJSON v)]
|]
| otherwise = case fieldShow field of
Nothing -> [| [( $nameE, JSON.showJSON $fvarE)] |]
- Just fn -> [| [( $nameE, JSON.showJSON . $fn $ $fvarE)] |]
- where isContainer = fieldIsContainer field
- fisOptional = fieldIsOptional field
+ Just fn -> [| let (actual, extra) = $fn $fvarE
+ in extra ++ [( $nameE, JSON.showJSON actual)]
+ |]
+ where fisOptional = fieldIsOptional field
nameE = stringE (fieldName field)
fvarE = varE fvar
-objectShowJSON :: String -> Q [Dec]
-objectShowJSON name =
- [d| showJSON = JSON.showJSON . $(varE . mkName $ "save" ++ name) |]
+objectShowJSON :: String -> Q Dec
+objectShowJSON name = do
+ body <- [| JSON.showJSON . $(varE . mkName $ "save" ++ name) |]
+ return $ FunD (mkName "showJSON") [Clause [] (NormalB body) []]
genLoadObject :: (Field -> Q (Name, Stmt))
-> String -> [Field] -> Q (Dec, Dec)
loadObjectField :: Field -> Q (Name, Stmt)
loadObjectField field = do
let name = fieldVariable field
- fvar = mkName name
+ fvar <- newName name
-- these are used in all patterns below
let objvar = varNameE "o"
objfield = stringE (fieldName field)
[| $(varNameE "fromObjWithDefault") $objvar
$objfield $defv |]
Nothing -> [| $(varNameE "fromObj") $objvar $objfield |]
- bexp <- loadFn field loadexp
+ bexp <- loadFn field loadexp objvar
return (fvar, BindS (VarP fvar) bexp)
fields_p <- mapM (paramFieldTypeInfo field_pfx) fields
let decl_f = RecC name_f fields_f
decl_p = RecC name_p fields_p
- let declF = DataD [] name_f [] [decl_f] [''Show, ''Read]
- declP = DataD [] name_p [] [decl_p] [''Show, ''Read]
+ let declF = DataD [] name_f [] [decl_f] [''Show, ''Read, ''Eq]
+ declP = DataD [] name_p [] [decl_p] [''Show, ''Read, ''Eq]
ser_decls_f <- buildObjectSerialisation sname_f fields
ser_decls_p <- buildPParamSerialisation sname_p fields
fill_decls <- fillParam sname field_pfx fields
shjson <- objectShowJSON sname
rdjson <- objectReadJSON sname
let instdecl = InstanceD [] (AppT (ConT ''JSON.JSON) (ConT name))
- (rdjson:shjson)
+ [rdjson, shjson]
return $ savedecls ++ [loadsig, loadfn, instdecl]
savePParamField :: Name -> Field -> Q Exp
loadPParamField field = do
checkNonOptDef field
let name = fieldName field
- fvar = mkName name
+ fvar <- newName name
-- these are used in all patterns below
let objvar = varNameE "o"
objfield = stringE name
loadexp = [| $(varNameE "maybeFromObj") $objvar $objfield |]
- bexp <- loadFn field loadexp
+ bexp <- loadFn field loadexp objvar
return (fvar, BindS (VarP fvar) bexp)
-- | Builds a simple declaration of type @n_x = fromMaybe f_x p_x@.
projects / ganeti-local / blobdiff