hprotoc-1.0.0: Text/ProtocolBuffers/ProtoCompile/MakeReflections.hs
-- | The 'MakeReflections' module takes the 'FileDescriptorProto'
-- output from 'Resolve' and produces a 'ProtoInfo' from
-- 'Reflections'. This also takes a Haskell module prefix and the
-- proto's package namespace as input. The output is suitable
-- for passing to the 'Gen' module to produce the files.
--
-- This acheives several things: It moves the data from a nested tree
-- to flat lists and maps. It moves the group information from the
-- parent Descriptor to the actual Descriptor. It moves the data out
-- of Maybe types. It converts Utf8 to String. Keys known to extend
-- a Descriptor are listed in that Descriptor.
--
-- In building the reflection info new things are computed. It changes
-- dotted names to ProtoName useing the translator from
-- 'makeNameMaps'. It parses the default value from the ByteString to
-- a Haskell type. For fields, the value of the tag on the wire is
-- computed and so is its size on the wire.
module Text.ProtocolBuffers.ProtoCompile.MakeReflections(makeProtoInfo,serializeFDP) where
import qualified Text.DescriptorProtos.DescriptorProto as D(DescriptorProto)
import qualified Text.DescriptorProtos.DescriptorProto as D.DescriptorProto(DescriptorProto(..))
import qualified Text.DescriptorProtos.DescriptorProto.ExtensionRange as D.DescriptorProto(ExtensionRange(ExtensionRange))
import qualified Text.DescriptorProtos.DescriptorProto.ExtensionRange as D.DescriptorProto.ExtensionRange(ExtensionRange(..))
import qualified Text.DescriptorProtos.EnumDescriptorProto as D(EnumDescriptorProto)
import qualified Text.DescriptorProtos.EnumDescriptorProto as D.EnumDescriptorProto(EnumDescriptorProto(..))
import qualified Text.DescriptorProtos.EnumValueDescriptorProto as D(EnumValueDescriptorProto)
import qualified Text.DescriptorProtos.EnumValueDescriptorProto as D.EnumValueDescriptorProto(EnumValueDescriptorProto(..))
import qualified Text.DescriptorProtos.FieldDescriptorProto as D(FieldDescriptorProto)
import qualified Text.DescriptorProtos.FieldDescriptorProto as D.FieldDescriptorProto(FieldDescriptorProto(..))
import qualified Text.DescriptorProtos.FieldDescriptorProto.Label as D.FieldDescriptorProto(Label)
import Text.DescriptorProtos.FieldDescriptorProto.Label as D.FieldDescriptorProto.Label(Label(..))
import qualified Text.DescriptorProtos.FieldDescriptorProto.Type as D.FieldDescriptorProto(Type)
import Text.DescriptorProtos.FieldDescriptorProto.Type as D.FieldDescriptorProto.Type(Type(..))
import qualified Text.DescriptorProtos.FileDescriptorProto as D(FileDescriptorProto(FileDescriptorProto))
import qualified Text.DescriptorProtos.FileDescriptorProto as D.FileDescriptorProto(FileDescriptorProto(..))
import Text.ProtocolBuffers.Basic
import Text.ProtocolBuffers.Identifiers
import Text.ProtocolBuffers.Reflections
import Text.ProtocolBuffers.WireMessage(size'Varint,toWireTag,runPut)
import Text.ProtocolBuffers.ProtoCompile.Resolve(ReMap,NameMap(..))
import qualified Data.Foldable as F(foldr,toList)
import qualified Data.ByteString.Lazy.UTF8 as U(fromString,toString)
import qualified Data.Sequence as Seq(fromList,empty,singleton,null)
import Numeric(readHex,readOct,readDec)
import Data.Monoid(mconcat,mappend)
import qualified Data.Map as M(fromListWith,lookup,keys)
import Data.Maybe(fromMaybe,catMaybes,fromJust)
import System.FilePath
--import Debug.Trace (trace)
imp :: String -> a
imp msg = error $ "Text.ProtocolBuffers.ProtoCompile.MakeReflections: Impossible?\n "++msg
pnPath :: ProtoName -> [FilePath]
pnPath (ProtoName _ a b c) = splitDirectories .flip addExtension "hs" . joinPath . map mName $ a++b++[c]
serializeFDP :: D.FileDescriptorProto -> ByteString
serializeFDP fdp = runPut (wirePut 11 fdp)
toHaskell :: ReMap -> FIName Utf8 -> ProtoName
toHaskell reMap k = case M.lookup k reMap of
Nothing -> imp $ "toHaskell failed to find "++show k++" among "++show (M.keys reMap)
Just pn -> pn
makeProtoInfo :: Bool -> NameMap -> D.FileDescriptorProto -> ProtoInfo
makeProtoInfo unknownField (NameMap (packageName,hPrefix,hParent) reMap)
fdp@(D.FileDescriptorProto { D.FileDescriptorProto.name = Just rawName })
= ProtoInfo protoName (pnPath protoName) (toString rawName) keyInfos allMessages allEnums allKeys where
protoName = case hParent of
[] -> case hPrefix of
[] -> imp $ "makeProtoInfo: no hPrefix or hParent in NameMap for: "++show fdp
_ -> ProtoName packageName (init hPrefix) [] (last hPrefix)
_ -> ProtoName packageName hPrefix (init hParent) (last hParent)
keyInfos = Seq.fromList . map (\f -> (keyExtendee' reMap f,toFieldInfo' reMap packageName f))
. F.toList . D.FileDescriptorProto.extension $ fdp
allMessages = concatMap (processMSG packageName False) (F.toList $ D.FileDescriptorProto.message_type fdp)
allEnums = map (makeEnumInfo' reMap packageName) (F.toList $ D.FileDescriptorProto.enum_type fdp)
++ concatMap (processENM packageName) (F.toList $ D.FileDescriptorProto.message_type fdp)
allKeys = M.fromListWith mappend . map (\(k,a) -> (k,Seq.singleton a))
. F.toList . mconcat $ keyInfos : map keys allMessages
processMSG parent msgIsGroup msg =
let getKnownKeys protoName' = fromMaybe Seq.empty (M.lookup protoName' allKeys)
groups = collectedGroups msg
checkGroup x = elem (fromMaybe (imp $ "no message name in makeProtoInfo.processMSG.checkGroup:\n"++show msg)
(D.DescriptorProto.name x))
groups
parent' = fqAppend parent [IName (fromJust (D.DescriptorProto.name msg))]
in makeDescriptorInfo' reMap parent getKnownKeys msgIsGroup unknownField msg
: concatMap (\x -> processMSG parent' (checkGroup x) x)
(F.toList (D.DescriptorProto.nested_type msg))
processENM parent msg = foldr ((:) . makeEnumInfo' reMap parent') nested
(F.toList (D.DescriptorProto.enum_type msg))
where parent' = fqAppend parent [IName (fromJust (D.DescriptorProto.name msg))]
nested = concatMap (processENM parent') (F.toList (D.DescriptorProto.nested_type msg))
makeProtoInfo _ _ _ = imp $ "makeProtoInfo: missing name or package"
makeEnumInfo' :: ReMap -> FIName Utf8 -> D.EnumDescriptorProto -> EnumInfo
makeEnumInfo' reMap parent
e@(D.EnumDescriptorProto.EnumDescriptorProto
{ D.EnumDescriptorProto.name = Just rawName
, D.EnumDescriptorProto.value = value })
= if Seq.null value then imp $ "enum has no values: "++show e
else EnumInfo protoName (pnPath protoName) enumVals
where protoName = toHaskell reMap $ fqAppend parent [IName rawName]
enumVals ::[(EnumCode,String)]
enumVals = F.foldr ((:) . oneValue) [] value
where oneValue :: D.EnumValueDescriptorProto -> (EnumCode,String)
oneValue (D.EnumValueDescriptorProto.EnumValueDescriptorProto
{ D.EnumValueDescriptorProto.name = Just name
, D.EnumValueDescriptorProto.number = Just number })
= (EnumCode number,mName . baseName . toHaskell reMap $ fqAppend (protobufName protoName) [IName name])
oneValue evdp = imp $ "no name or number for evdp passed to makeEnumInfo.oneValue: "++show evdp
makeEnumInfo' _ _ _ = imp "makeEnumInfo: missing name"
keyExtendee' :: ReMap -> D.FieldDescriptorProto.FieldDescriptorProto -> ProtoName
keyExtendee' reMap f = case D.FieldDescriptorProto.extendee f of
Nothing -> imp $ "keyExtendee expected Just but found Nothing: "++show f
Just extName -> toHaskell reMap (FIName extName)
makeDescriptorInfo' :: ReMap -> FIName Utf8
-> (ProtoName -> Seq FieldInfo)
-> Bool -> Bool
-> D.DescriptorProto -> DescriptorInfo
makeDescriptorInfo' reMap parent getKnownKeys msgIsGroup unknownField
(D.DescriptorProto.DescriptorProto
{ D.DescriptorProto.name = Just rawName
, D.DescriptorProto.field = rawFields
, D.DescriptorProto.extension = rawKeys
, D.DescriptorProto.extension_range = extension_range })
= let di = DescriptorInfo protoName (pnPath protoName) msgIsGroup
fieldInfos keyInfos extRangeList (getKnownKeys protoName)
unknownField
in di -- trace (toString rawName ++ "\n" ++ show di ++ "\n\n") $ di
where protoName = toHaskell reMap $ fqAppend parent [IName rawName]
fieldInfos = fmap (toFieldInfo' reMap (protobufName protoName)) rawFields
keyInfos = fmap (\f -> (keyExtendee' reMap f,toFieldInfo' reMap (protobufName protoName) f)) rawKeys
extRangeList = concatMap check unchecked
where check x@(lo,hi) | hi < lo = []
| hi<19000 || 19999<lo = [x]
| otherwise = concatMap check [(lo,18999),(20000,hi)]
unchecked = F.foldr ((:) . extToPair) [] extension_range
extToPair (D.DescriptorProto.ExtensionRange
{ D.DescriptorProto.ExtensionRange.start = mStart
, D.DescriptorProto.ExtensionRange.end = mEnd }) =
(maybe minBound FieldId mStart, maybe maxBound (FieldId . pred) mEnd)
makeDescriptorInfo' _ _ _ _ _ _ = imp $ "makeDescriptorInfo: missing name"
toFieldInfo' :: ReMap -> FIName Utf8 -> D.FieldDescriptorProto -> FieldInfo
toFieldInfo' reMap parent
f@(D.FieldDescriptorProto.FieldDescriptorProto
{ D.FieldDescriptorProto.name = Just name
, D.FieldDescriptorProto.number = Just number
, D.FieldDescriptorProto.label = Just label
, D.FieldDescriptorProto.type' = Just type'
, D.FieldDescriptorProto.type_name = mayTypeName
, D.FieldDescriptorProto.default_value = mayRawDef })
= fieldInfo
where mayDef = parseDefaultValue f
fieldInfo = let (ProtoName x a b c) = toHaskell reMap $ fqAppend parent [IName name]
protoFName = ProtoFName x a b (mangle c)
fieldId = (FieldId (fromIntegral number))
fieldType = (FieldType (fromEnum type'))
wt = toWireTag fieldId fieldType
wtLength = size'Varint (getWireTag wt)
in FieldInfo protoFName
fieldId
wt
wtLength
(label == LABEL_REQUIRED)
(label == LABEL_REPEATED)
fieldType
(fmap (toHaskell reMap . FIName) mayTypeName)
(fmap utf8 mayRawDef)
mayDef
toFieldInfo' _ _ f = imp $ "toFieldInfo: missing info in "++show f
collectedGroups :: D.DescriptorProto -> [Utf8]
collectedGroups = catMaybes
. map D.FieldDescriptorProto.type_name
. filter (\f -> D.FieldDescriptorProto.type' f == Just TYPE_GROUP)
. F.toList
. D.DescriptorProto.field
-- "Nothing" means no value specified
-- A failure to parse a provided value will result in an error at the moment
parseDefaultValue :: D.FieldDescriptorProto -> Maybe HsDefault
parseDefaultValue f@(D.FieldDescriptorProto.FieldDescriptorProto
{ D.FieldDescriptorProto.type' = type'
, D.FieldDescriptorProto.default_value = mayRawDef })
= do bs <- mayRawDef
t <- type'
todo <- case t of
TYPE_MESSAGE -> Nothing
TYPE_GROUP -> Nothing
TYPE_ENUM -> Just parseDefEnum
TYPE_BOOL -> Just parseDefBool
TYPE_BYTES -> Just parseDefBytes
TYPE_DOUBLE -> Just parseDefDouble
TYPE_FLOAT -> Just parseDefFloat
TYPE_STRING -> Just parseDefString
_ -> Just parseDefInteger
case todo (utf8 bs) of
Nothing -> error $ "Could not parse as type "++ show t ++"the default value "++ show mayRawDef ++" for field "++show f
Just value -> return value
--- From here down is code used to parse the format of the default values in the .proto files
parseDefEnum :: ByteString -> Maybe HsDefault
parseDefEnum = Just . HsDef'Enum . U.toString
{-# INLINE mayRead #-}
mayRead :: ReadS a -> String -> Maybe a
mayRead f s = case f s of [(a,"")] -> Just a; _ -> Nothing
parseDefDouble :: ByteString -> Maybe HsDefault
parseDefDouble bs = fmap (HsDef'Rational . toRational)
. mayRead reads' . U.toString $ bs
where reads' :: ReadS Double
reads' = readSigned' reads
parseDefFloat :: ByteString -> Maybe HsDefault
parseDefFloat bs = fmap (HsDef'Rational . toRational)
. mayRead reads' . U.toString $ bs
where reads' :: ReadS Float
reads' = readSigned' reads
parseDefString :: ByteString -> Maybe HsDefault
parseDefString bs = Just (HsDef'ByteString bs)
parseDefBytes :: ByteString -> Maybe HsDefault
parseDefBytes bs = Just (HsDef'ByteString bs)
parseDefInteger :: ByteString -> Maybe HsDefault
parseDefInteger bs = fmap HsDef'Integer . mayRead checkSign . U.toString $ bs
where checkSign = readSigned' checkBase
checkBase ('0':'x':xs) = readHex xs
checkBase ('0':xs) = readOct xs
checkBase xs = readDec xs
parseDefBool :: ByteString -> Maybe HsDefault
parseDefBool bs | bs == U.fromString "true" = Just (HsDef'Bool True)
| bs == U.fromString "false" = Just (HsDef'Bool False)
| otherwise = Nothing
-- The Numeric.readSigned does not handle '+' for some odd reason
readSigned' :: (Num a) => ([Char] -> [(a, t)]) -> [Char] -> [(a, t)]
readSigned' f ('-':xs) = map (\(v,s) -> (-v,s)) . f $ xs
readSigned' f ('+':xs) = f xs
readSigned' f xs = f xs