Database.DynamoDB.Types

Exceptions

data DynamoException

Exceptions thrown by some dynamodb-simple actions.

Constructors

DynamoException Text

Instances

Show DynamoException

Methods

showsPrec :: Int -> DynamoException -> ShowS

show :: DynamoException -> String

showList :: [DynamoException] -> ShowS

Exception DynamoException

Methods

toException :: DynamoException -> SomeException

fromException :: SomeException -> Maybe DynamoException

displayException :: DynamoException -> String

Marshalling

class DynamoEncodable a where

Typeclass showing that this datatype can be saved to DynamoDB.

Methods

dEncode :: a -> Maybe AttributeValue

Encode data. Return Nothing if attribute should be omitted.

dEncode :: (Show a, Read a) => a -> Maybe AttributeValue

Encode data. Return Nothing if attribute should be omitted.

dDecode :: Maybe AttributeValue -> Maybe a

Decode data. Return Nothing on parsing error, gets Nothing on input if the attribute was missing in the database.

dDecode :: (Show a, Read a) => Maybe AttributeValue -> Maybe a

Decode data. Return Nothing on parsing error, gets Nothing on input if the attribute was missing in the database.

dDecodeEither :: Maybe AttributeValue -> Either Text a

Decode data. Return (Left err) on parsing error, gets Nothing on input if the attribute was missing in the database. The default instance uses dDecode, define this just for better errors

dIsMissing :: a -> Bool

Aid for searching for empty list and hashmap; these can be represented both by empty list and by missing value, if this returns true, enhance search. Also used by joins to weed out empty foreign keys

Instances

DynamoEncodable Bool

Methods

dEncode :: Bool -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Bool

dDecodeEither :: Maybe AttributeValue -> Either Text Bool

dIsMissing :: Bool -> Bool

DynamoEncodable Double

Methods

dEncode :: Double -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Double

dDecodeEither :: Maybe AttributeValue -> Either Text Double

dIsMissing :: Double -> Bool

DynamoEncodable Int

Methods

dEncode :: Int -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Int

dDecodeEither :: Maybe AttributeValue -> Either Text Int

dIsMissing :: Int -> Bool

DynamoEncodable Int16

Methods

dEncode :: Int16 -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Int16

dDecodeEither :: Maybe AttributeValue -> Either Text Int16

dIsMissing :: Int16 -> Bool

DynamoEncodable Int32

Methods

dEncode :: Int32 -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Int32

dDecodeEither :: Maybe AttributeValue -> Either Text Int32

dIsMissing :: Int32 -> Bool

DynamoEncodable Int64

Methods

dEncode :: Int64 -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Int64

dDecodeEither :: Maybe AttributeValue -> Either Text Int64

dIsMissing :: Int64 -> Bool

DynamoEncodable Integer

Methods

dEncode :: Integer -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Integer

dDecodeEither :: Maybe AttributeValue -> Either Text Integer

dIsMissing :: Integer -> Bool

DynamoEncodable Word

Methods

dEncode :: Word -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Word

dDecodeEither :: Maybe AttributeValue -> Either Text Word

dIsMissing :: Word -> Bool

DynamoEncodable ByteString

Methods

dEncode :: ByteString -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe ByteString

dDecodeEither :: Maybe AttributeValue -> Either Text ByteString

dIsMissing :: ByteString -> Bool

DynamoEncodable Scientific

Methods

dEncode :: Scientific -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Scientific

dDecodeEither :: Maybe AttributeValue -> Either Text Scientific

dIsMissing :: Scientific -> Bool

DynamoEncodable Text

Methods

dEncode :: Text -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Text

dDecodeEither :: Maybe AttributeValue -> Either Text Text

dIsMissing :: Text -> Bool

DynamoEncodable Value

Partial encoding/decoding Aeson values. Empty strings get converted to NULL.

Methods

dEncode :: Value -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe Value

dDecodeEither :: Maybe AttributeValue -> Either Text Value

dIsMissing :: Value -> Bool

DynamoEncodable UUID

Methods

dEncode :: UUID -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe UUID

dDecodeEither :: Maybe AttributeValue -> Either Text UUID

dIsMissing :: UUID -> Bool

DynamoEncodable a => DynamoEncodable [a]

DynamoDB cannot represent empty items; [Maybe a] will lose Nothings.

Methods

dEncode :: [a] -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe [a]

dDecodeEither :: Maybe AttributeValue -> Either Text [a]

dIsMissing :: [a] -> Bool

DynamoEncodable a => DynamoEncodable (Maybe a)

Maybe (Maybe a) will not work well; it will join the value in the database.

Methods

dEncode :: Maybe a -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe (Maybe a)

dDecodeEither :: Maybe AttributeValue -> Either Text (Maybe a)

dIsMissing :: Maybe a -> Bool

(Ord a, DynamoScalar v a) => DynamoEncodable (Set a)

Methods

dEncode :: Set a -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe (Set a)

dDecodeEither :: Maybe AttributeValue -> Either Text (Set a)

dIsMissing :: Set a -> Bool

(IsText t, DynamoEncodable a) => DynamoEncodable (HashMap t a)

Methods

dEncode :: HashMap t a -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe (HashMap t a)

dDecodeEither :: Maybe AttributeValue -> Either Text (HashMap t a)

dIsMissing :: HashMap t a -> Bool

DynamoEncodable a => DynamoEncodable (Tagged * v a)

Methods

dEncode :: Tagged * v a -> Maybe AttributeValue

dDecode :: Maybe AttributeValue -> Maybe (Tagged * v a)

dDecodeEither :: Maybe AttributeValue -> Either Text (Tagged * v a)

dIsMissing :: Tagged * v a -> Bool

class ScalarAuto v => DynamoScalar (v :: ScalarAttributeType) a | a -> v where

Typeclass signifying that this is a scalar attribute and can be used as a hash/sort key.

instance DynamoScalar Network.AWS.DynamoDB.Types.S T.Text where
   scalarEncode = ScS
   scalarDecode (ScS txt) = Just txt

Methods

scalarEncode :: a -> ScalarValue v

Scalars must have total encoding function

scalarEncode :: (Show a, Read a, v ~ S) => a -> ScalarValue v

Scalars must have total encoding function

scalarDecode :: ScalarValue v -> Maybe a

scalarDecode :: (Show a, Read a, v ~ S) => ScalarValue v -> Maybe a

Instances

DynamoScalar S Text

Methods

scalarEncode :: Text -> ScalarValue S

scalarDecode :: ScalarValue S -> Maybe Text

DynamoScalar S UUID

Methods

scalarEncode :: UUID -> ScalarValue S

scalarDecode :: ScalarValue S -> Maybe UUID

DynamoScalar N Double

Don't use Double as a part of primary key in a table. It is included here for convenience to be used as a range key in indexes.

Methods

scalarEncode :: Double -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Double

DynamoScalar N Int

Methods

scalarEncode :: Int -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Int

DynamoScalar N Int16

Methods

scalarEncode :: Int16 -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Int16

DynamoScalar N Int32

Methods

scalarEncode :: Int32 -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Int32

DynamoScalar N Int64

Methods

scalarEncode :: Int64 -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Int64

DynamoScalar N Integer

Methods

scalarEncode :: Integer -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Integer

DynamoScalar N Word

Methods

scalarEncode :: Word -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Word

DynamoScalar N Scientific

Double as a primary key isn't generally a good thing as equality on double is sometimes a little dodgy. Use scientific instead.

Methods

scalarEncode :: Scientific -> ScalarValue N

scalarDecode :: ScalarValue N -> Maybe Scientific

DynamoScalar B ByteString

Methods

scalarEncode :: ByteString -> ScalarValue B

scalarDecode :: ScalarValue B -> Maybe ByteString

DynamoScalar v a => DynamoScalar v (Tagged * x a)

Helper for tagged values

Methods

scalarEncode :: Tagged * x a -> ScalarValue v

scalarDecode :: ScalarValue v -> Maybe (Tagged * x a)

data ScalarValue (v :: ScalarAttributeType) where

Datatype for encoding scalar values

Constructors

ScS :: !Text -> ScalarValue S

ScN :: !Scientific -> ScalarValue N

ScB :: !ByteString -> ScalarValue B

class (Eq a, Hashable a) => IsText a where

Class to limit certain operations to text-like only in queries. Members of this class can be keys to HashMap.

Minimal complete definition

toText, fromText

Methods

toText :: a -> Text

fromText :: Text -> a

Instances

IsText Text

Methods

toText :: Text -> Text

fromText :: Text -> Text

(Hashable (Tagged * t a), IsText a) => IsText (Tagged * t a)

Methods

toText :: Tagged * t a -> Text

fromText :: Text -> Tagged * t a

class IsNumber a

Class to limit +=. and -=. for updates.

Instances

IsNumber Double

IsNumber Int

IsNumber Integer

IsNumber a => IsNumber (Tagged * t a)

Query datatype

data RangeOper a where

Operation on range key for query.

Constructors

RangeEquals :: a -> RangeOper a

RangeLessThan :: a -> RangeOper a

RangeLessThanE :: a -> RangeOper a

RangeGreaterThan :: a -> RangeOper a

RangeGreaterThanE :: a -> RangeOper a

RangeBetween :: a -> a -> RangeOper a

RangeBeginsWith :: IsText a => a -> RangeOper a

Utility functions

dType :: forall a v. DynamoScalar v a => Proxy a -> ScalarAttributeType

dScalarEncode :: DynamoScalar v a => a -> AttributeValue