mongodb/Database/MongoDB/BSON.hs

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{-
Copyright (C) 2010 Scott R Parish <srp@srparish.net>
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-}
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module Database.MongoDB.BSON
(
-- * Types
BsonValue(..),
BsonDoc,
BinarySubType(..),
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-- * BsonDoc Operations
empty,
-- * Type Conversion
fromBson, toBson,
fromBsonDoc, toBsonDoc,
-- * Binary encoding/decoding
getBsonDoc, putBsonDoc,
-- * ObjectId creation
ObjectIdGen, mkObjectIdGen, genObjectId,
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)
where
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import Prelude hiding (lookup)
import qualified Control.Arrow as Arrow
import Control.Exception
import Control.Monad
import Data.Binary
import Data.Binary.Get
import Data.Binary.IEEE754
import Data.Binary.Put
import Data.Bits
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import Data.ByteString.Char8 as C8 hiding (empty)
import qualified Data.ByteString.Lazy as L
import qualified Data.ByteString.Lazy.UTF8 as L8
import qualified Data.ByteString.UTF8 as S8
import Data.Digest.OpenSSL.MD5
import Data.Int
import Data.IORef
import qualified Data.List as List
import qualified Data.Map as Map
import Data.Time.Clock.POSIX
import Data.Typeable
import Database.MongoDB.Util
import Network.BSD
import Numeric
import System.IO.Unsafe
import System.Posix.Process
-- | BsonValue is the type that can be used as a value in a 'BsonDoc'.
data BsonValue
= BsonDouble Double
| BsonString L8.ByteString
| BsonDoc BsonDoc
| BsonArray [BsonValue]
| BsonUndefined
| BsonBinary BinarySubType L.ByteString
| BsonObjectId Integer
| BsonBool !Bool
| BsonDate POSIXTime
| BsonNull
| BsonRegex L8.ByteString String
| BsonJSCode L8.ByteString
| BsonSymbol L8.ByteString
| BsonJSCodeWScope L8.ByteString BsonDoc
| BsonInt32 Int32
| BsonInt64 Int64
| BsonMinKey
| BsonMaxKey
deriving (Show, Eq, Ord)
type BsonDoc = [(L8.ByteString, BsonValue)]
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-- | An empty BsonDoc
empty :: BsonDoc
empty = []
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data DataType =
DataMinKey | -- -1
DataNumber | -- 1
DataString | -- 2
DataDoc | -- 3
DataArray | -- 4
DataBinary | -- 5
DataUndefined | -- 6
DataOid | -- 7
DataBoolean | -- 8
DataDate | -- 9
DataNull | -- 10
DataRegex | -- 11
DataRef | -- 12
DataJSCode | -- 13
DataSymbol | -- 14
DataJSCodeWScope | -- 15
DataInt | -- 16
DataTimestamp | -- 17
DataLong | -- 18
DataMaxKey -- 127
deriving (Show, Read, Enum, Eq, Ord)
toDataType :: Int -> DataType
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toDataType (-1) = DataMinKey
toDataType 127 = DataMaxKey
toDataType d = toEnum d
fromDataType :: DataType -> Int8
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fromDataType DataMinKey = - 1
fromDataType DataMaxKey = 127
fromDataType d = fromIntegral $ fromEnum d
data BinarySubType =
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BSTUNDEFINED1 |
BSTFunction | -- 1
BSTByteArray | -- 2
BSTUUID | -- 3
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BSTUNDEFINED2 |
BSTMD5 | -- 5
BSTUserDefined
deriving (Show, Read, Enum, Eq, Ord)
toBinarySubType :: Int -> BinarySubType
toBinarySubType 0x80 = BSTUserDefined
toBinarySubType d = toEnum d
fromBinarySubType :: BinarySubType -> Int8
fromBinarySubType BSTUserDefined = 0x80
fromBinarySubType d = fromIntegral $ fromEnum d
data ObjectIdGen = ObjectIdGen {
oigMachine :: Integer,
oigInc :: IORef Integer
}
globalObjectIdInc :: IORef Integer
{-# NOINLINE globalObjectIdInc #-}
globalObjectIdInc = unsafePerformIO (newIORef 0)
-- | Create a new 'ObjectIdGen', the structure that must be passed to
-- genObjectId to create a 'ObjectId'.
mkObjectIdGen :: IO ObjectIdGen
mkObjectIdGen = do
host <- liftM (fst . (!! 0) . readHex . List.take 6 . md5sum . C8.pack)
getHostName
return ObjectIdGen {oigMachine = host, oigInc = globalObjectIdInc}
-- | Create a new 'ObjectId'.
genObjectId :: ObjectIdGen -> IO BsonValue
genObjectId oig = do
now <- liftM (truncate . (realToFrac :: POSIXTime -> Double)) getPOSIXTime
pid <- liftM fromIntegral getProcessID
inc <- atomicModifyIORef (oigInc oig) $ \i -> ((i+1) `rem` 0x10000, i)
return $ BsonObjectId
((now `shiftL` 64) .|.
oigMachine oig `shiftL` 40 .|.
(0xffff .&. pid) `shiftL` 24 .|.
(inc `div` 0x100) `shiftL` 8 .|. (inc `rem` 0x100))
-- | Decode binary bytes into 'BsonDoc'.
getBsonDoc :: Get BsonDoc
getBsonDoc = liftM snd getDoc
-- | Encode 'BsonDoc' into binary bytes.
putBsonDoc :: BsonDoc -> Put
putBsonDoc = putObj
getVal :: DataType -> Get (Integer, BsonValue)
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getVal DataNumber = liftM ((,) 8 . BsonDouble) getFloat64le
getVal DataString = do
sLen1 <- getI32
(_sLen2, s) <- getS
return (fromIntegral $ 4 + sLen1, BsonString s)
getVal DataDoc = getDoc >>= \(len, obj) -> return (len, BsonDoc obj)
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getVal DataArray = do
bytes <- getI32
arr <- getInnerArray (bytes - 4)
getNull
return (fromIntegral bytes, BsonArray arr)
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getVal DataBinary = do
len1 <- getI32
st <- getI8
(len, hdrLen) <- if toBinarySubType st == BSTByteArray
then do
len2 <- getI32
assert (len1 - 4 == len2) $ return ()
return (len2, 4 + 1 + 4)
else return (len1, 4 + 1)
bs <- getLazyByteString $ fromIntegral len
return (hdrLen + fromIntegral len, BsonBinary (toBinarySubType st) bs)
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getVal DataUndefined = return (1, BsonUndefined)
getVal DataOid = do
oid1 <- getWord64be
oid2 <- getWord32be
let oid = (fromIntegral oid1 `shiftL` 32) .|. fromIntegral oid2
return (12, BsonObjectId oid)
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getVal DataBoolean = liftM ((,) (1::Integer) . BsonBool . (/= (0::Int))) getI8
getVal DataDate = liftM ((,) 8 . BsonDate . flip (/) 1000 . realToFrac) getI64
getVal DataNull = return (1, BsonNull)
getVal DataRegex = fail "DataJSCode not yet supported" -- TODO
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getVal DataRef = fail "DataRef is deprecated"
getVal DataJSCode = do
sLen1 <- getI32
(_sLen2, s) <- getS
return (fromIntegral $ 4 + sLen1, BsonJSCode s)
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getVal DataSymbol = do
sLen1 <- getI32
(_sLen2, s) <- getS
return (fromIntegral $ 4 + sLen1, BsonString s)
getVal DataJSCodeWScope = do
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sLen1 <- getI32
(_, qry) <- getS
(_, scope) <- getDoc
return (fromIntegral sLen1, BsonJSCodeWScope qry scope)
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getVal DataInt = liftM ((,) 4 . BsonInt32 . fromIntegral) getI32
getVal DataTimestamp = fail "DataTimestamp not yet supported" -- TODO
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getVal DataLong = liftM ((,) 8 . BsonInt64) getI64
getVal DataMinKey = return (0, BsonMinKey)
getVal DataMaxKey = return (0, BsonMaxKey)
getInnerObj :: Int32 -> Get BsonDoc
getInnerObj 1 = return []
getInnerObj bytesLeft = do
typ <- getDataType
(keySz, key) <- getS
(valSz, val) <- getVal typ
rest <- getInnerObj (bytesLeft - 1 - fromIntegral keySz - fromIntegral valSz)
return $ (key, val) : rest
getRawObj :: Get (Integer, BsonDoc)
getRawObj = do
bytes <- getI32
obj <- getInnerObj (bytes - 4)
getNull
return (fromIntegral bytes, obj)
getInnerArray :: Int32 -> Get [BsonValue]
getInnerArray 1 = return []
getInnerArray bytesLeft = do
typ <- getDataType
(keySz, _key) <- getS
(valSz, val) <- getVal typ
rest <- getInnerArray
(bytesLeft - 1 - fromIntegral keySz - fromIntegral valSz)
return $ val : rest
getDoc :: Get (Integer, BsonDoc)
getDoc = getRawObj
getDataType :: Get DataType
getDataType = liftM toDataType getI8
putType :: BsonValue -> Put
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putType BsonDouble{} = putDataType DataNumber
putType BsonString{} = putDataType DataString
putType BsonDoc{} = putDataType DataDoc
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putType BsonArray{} = putDataType DataArray
putType BsonBinary{} = putDataType DataBinary
putType BsonUndefined = putDataType DataUndefined
putType BsonObjectId{} = putDataType DataOid
putType BsonBool{} = putDataType DataBoolean
putType BsonDate{} = putDataType DataDate
putType BsonNull = putDataType DataNull
putType BsonRegex{} = putDataType DataRegex
-- putType = putDataType DataRef
putType BsonJSCode {} = putDataType DataJSCode
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putType BsonSymbol{} = putDataType DataSymbol
putType BsonJSCodeWScope{} = putDataType DataJSCodeWScope
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putType BsonInt32 {} = putDataType DataInt
putType BsonInt64 {} = putDataType DataLong
-- putType = putDataType DataTimestamp
putType BsonMinKey = putDataType DataMinKey
putType BsonMaxKey = putDataType DataMaxKey
putVal :: BsonValue -> Put
putVal (BsonDouble d) = putFloat64le d
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putVal (BsonString s) = putStrSz s
putVal (BsonDoc o) = putObj o
putVal (BsonArray es) = putOutterObj bs
where bs = runPut $ forM_ (List.zip [(0::Int) .. ] es) $ \(i, e) ->
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putType e >> putS (L8.fromString $ show i) >> putVal e
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putVal (BsonBinary t bs) = do
putI32 $ fromIntegral $ (if t == BSTByteArray then 4 else 0) + L.length bs
putI8 $ fromBinarySubType t
when (t == BSTByteArray) $ putI32 $ fromIntegral $ L.length bs
putLazyByteString bs
putVal BsonUndefined = putNothing
putVal (BsonObjectId o) = putWord64be (fromIntegral $ o `shiftR` 32) >>
putWord32be (fromIntegral $ o .&. 0xffffffff)
putVal (BsonBool False) = putI8 0
putVal (BsonBool True) = putI8 1
putVal (BsonDate pt) = putI64 $ round $ 1000 * (realToFrac pt :: Double)
putVal BsonNull = putNothing
putVal (BsonRegex r opt)= do putS r
putByteString $ pack $ List.sort opt
putNull
putVal (BsonJSCode c) = putStrSz c
putVal (BsonSymbol s) = putI32 (fromIntegral $ 1 + L8.length s) >> putS s
putVal (BsonJSCodeWScope q s) =
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let bytes = runPut (putStrSz q >> putObj s)
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in putI32 ((+4) $ fromIntegral $ L.length bytes) >> putLazyByteString bytes
putVal (BsonInt32 i) = putI32 i
putVal (BsonInt64 i) = putI64 i
putVal BsonMinKey = putNothing
putVal BsonMaxKey = putNothing
putObj :: BsonDoc -> Put
putObj obj = putOutterObj bs
where bs = runPut $ forM_ obj $ \(k, v) -> putType v >> putS k >> putVal v
putOutterObj :: L.ByteString -> Put
putOutterObj bytes = do
-- the length prefix and null term are included in the length
putI32 $ fromIntegral $ 4 + 1 + L.length bytes
putLazyByteString bytes
putNull
putDataType :: DataType -> Put
putDataType = putI8 . fromDataType
class BsonDocConv a where
-- | Convert a BsonDoc into another form such as a Map or a tuple
-- list with String keys.
fromBsonDoc :: BsonDoc -> a
-- | Convert a Map or a tuple list with String keys into a BsonDoc.
toBsonDoc :: a -> BsonDoc
instance BsonDocConv [(L8.ByteString, BsonValue)] where
fromBsonDoc = id
toBsonDoc = id
instance BsonDocConv [(String, BsonValue)] where
fromBsonDoc = List.map $ Arrow.first L8.toString
toBsonDoc = List.map $ Arrow.first L8.fromString
instance BsonDocConv (Map.Map L8.ByteString BsonValue) where
fromBsonDoc = Map.fromList
toBsonDoc = Map.toList
instance BsonDocConv (Map.Map String BsonValue) where
fromBsonDoc = Map.fromList . fromBsonDoc
toBsonDoc = toBsonDoc . Map.toList
data BsonUnsupportedConversion = BsonUnsupportedConversion
deriving (Eq, Show, Read)
bsonUnsupportedConversion :: TyCon
bsonUnsupportedConversion =
mkTyCon "Database.MongoDB.BSON.BsonUnsupportedConversion "
instance Typeable BsonUnsupportedConversion where
typeOf _ = mkTyConApp bsonUnsupportedConversion []
instance Exception BsonUnsupportedConversion
throwUnsupConv :: a
throwUnsupConv = throw BsonUnsupportedConversion
class BsonConv a where
-- | Convert a native Haskell type into a BsonValue.
toBson :: a -> BsonValue
-- | Convert a BsonValue into a native Haskell type.
fromBson :: BsonValue -> a
instance BsonConv Double where
toBson = BsonDouble
fromBson (BsonDouble d) = d
fromBson _ = throwUnsupConv
instance BsonConv Float where
toBson = BsonDouble . realToFrac
fromBson (BsonDouble d) = realToFrac d
fromBson _ = throwUnsupConv
instance BsonConv L8.ByteString where
toBson = BsonString
fromBson (BsonString s) = s
fromBson _ = throwUnsupConv
instance BsonConv String where
toBson = BsonString . L8.fromString
fromBson (BsonString s) = L8.toString s
fromBson _ = throwUnsupConv
instance BsonConv S8.ByteString where
toBson bs = BsonString $ L.fromChunks [bs]
fromBson (BsonString s) = C8.concat $ L.toChunks s
fromBson _ = throwUnsupConv
instance BsonConv BsonDoc where
toBson = BsonDoc
fromBson (BsonDoc d) = d
fromBson _ = throwUnsupConv
instance BsonConv [(String, BsonValue)] where
toBson = toBson . toBsonDoc
fromBson (BsonDoc d) = fromBsonDoc d
fromBson _ = throwUnsupConv
instance BsonConv (Map.Map L8.ByteString BsonValue) where
toBson = toBson . toBsonDoc
fromBson (BsonDoc d) = fromBsonDoc d
fromBson _ = throwUnsupConv
instance BsonConv (Map.Map String BsonValue) where
toBson = toBson . toBsonDoc
fromBson (BsonDoc d) = fromBsonDoc d
fromBson _ = throwUnsupConv
instance BsonConv POSIXTime where
toBson = BsonDate
fromBson (BsonDate d) = d
fromBson _ = throwUnsupConv
instance BsonConv Bool where
toBson = BsonBool
fromBson (BsonBool b) = b
fromBson _ = throwUnsupConv
instance BsonConv Int where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Int8 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Int16 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Int32 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Int64 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Integer where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Word where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Word8 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Word16 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Word32 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv Word64 where
toBson i | i >= fromIntegral (minBound::Int32) &&
i <= fromIntegral (maxBound::Int32) = BsonInt32 $ fromIntegral i
| otherwise = BsonInt64 $ fromIntegral i
fromBson (BsonInt32 i) = fromIntegral i
fromBson (BsonInt64 i) = fromIntegral i
fromBson _ = throwUnsupConv
instance BsonConv [Double] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Float] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Int] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Int8] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Int16] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Int32] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Int64] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Integer] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Word] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Word8] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Word16] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Word32] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Word64] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [Bool] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [POSIXTime] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [String] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [L8.ByteString] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [S8.ByteString] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
instance BsonConv [BsonDoc] where
toBson = BsonArray . List.map toBson
fromBson (BsonArray ss) = List.map fromBson ss
fromBson _ = throwUnsupConv
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instance (BsonConv a) => BsonConv (Maybe a) where
toBson Nothing = BsonNull
toBson (Just a) = toBson a
fromBson BsonNull = Nothing
fromBson a = Just $ fromBson a