Safe Haskell	Safe-Inferred
Language	Haskell2010

Data.Store.Version

Description

This module provides utilities which help ensure that we aren't attempting to de-serialize data that is an older or newer version. The WithVersion utility wraps up a datatype along with a version tag. This version tag can either be provided by the user (namedVersionConfig), or use a computed hash (hashedVersionConfig).

The magic here is using an SYB traversal (Data) to get the structure of all the data-types involved. This info is rendered to text and hashed to yield a hash which describes it.

NOTE that this API is still quite new and so is likely to break compatibility in the future. It should also be expected that the computed hashes may change between major version bumps, though this will be minimized when directly feasible.

Synopsis

newtype StoreVersion = StoreVersion {
- unStoreVersion :: ByteString
}
data VersionConfig a = VersionConfig {
- vcExpectedHash :: Maybe String
- vcManualName :: Maybe String
- vcIgnore :: Set String
- vcRenames :: Map String String
}
hashedVersionConfig :: String -> VersionConfig a
namedVersionConfig :: String -> String -> VersionConfig a
encodeWithVersionQ :: Data a => VersionConfig a -> Q Exp
decodeWithVersionQ :: Data a => VersionConfig a -> Q Exp

Documentation

newtype StoreVersion Source #

Constructors

StoreVersion
Fields unStoreVersion :: ByteString

Instances

Instances details

Data StoreVersion Source #
Instance details Defined in Data.Store.Version Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> StoreVersion -> c StoreVersion # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c StoreVersion # toConstr :: StoreVersion -> Constr # dataTypeOf :: StoreVersion -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c StoreVersion) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c StoreVersion) # gmapT :: (forall b. Data b => b -> b) -> StoreVersion -> StoreVersion # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> StoreVersion -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> StoreVersion -> r # gmapQ :: (forall d. Data d => d -> u) -> StoreVersion -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> StoreVersion -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> StoreVersion -> m StoreVersion # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> StoreVersion -> m StoreVersion # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> StoreVersion -> m StoreVersion #
Generic StoreVersion Source #
Instance details Defined in Data.Store.Version Associated Types type Rep StoreVersion :: Type -> Type # Methods from :: StoreVersion -> Rep StoreVersion x # to :: Rep StoreVersion x -> StoreVersion #
Show StoreVersion Source #
Instance details Defined in Data.Store.Version Methods showsPrec :: Int -> StoreVersion -> ShowS # show :: StoreVersion -> String # showList :: [StoreVersion] -> ShowS #
Eq StoreVersion Source #
Instance details Defined in Data.Store.Version Methods (==) :: StoreVersion -> StoreVersion -> Bool # (/=) :: StoreVersion -> StoreVersion -> Bool #
Ord StoreVersion Source #
Instance details Defined in Data.Store.Version Methods compare :: StoreVersion -> StoreVersion -> Ordering # (<) :: StoreVersion -> StoreVersion -> Bool # (<=) :: StoreVersion -> StoreVersion -> Bool # (>) :: StoreVersion -> StoreVersion -> Bool # (>=) :: StoreVersion -> StoreVersion -> Bool # max :: StoreVersion -> StoreVersion -> StoreVersion # min :: StoreVersion -> StoreVersion -> StoreVersion #
Store StoreVersion Source #
Instance details Defined in Data.Store.Version Methods size :: Size StoreVersion Source # poke :: StoreVersion -> Poke () Source # peek :: Peek StoreVersion Source #
type Rep StoreVersion Source #
Instance details Defined in Data.Store.Version type Rep StoreVersion = D1 ('MetaData "StoreVersion" "Data.Store.Version" "store-0.7.18-JKaeHVOO5ISLnJjhQgwn0u" 'True) (C1 ('MetaCons "StoreVersion" 'PrefixI 'True) (S1 ('MetaSel ('Just "unStoreVersion") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ByteString)))

data VersionConfig a Source #

Configuration for the version checking of a particular type.

Constructors

VersionConfig
Fields vcExpectedHash :: Maybe String When set, specifies the hash which is expected to be computed. vcManualName :: Maybe String When set, specifies the name to instead use to tag the data. vcIgnore :: Set String DataTypes to ignore. vcRenames :: Map String String Allowed renamings of datatypes, useful when they move.

Instances

Instances details

Data a => Data (VersionConfig a) Source #
Instance details Defined in Data.Store.Version Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> VersionConfig a -> c (VersionConfig a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (VersionConfig a) # toConstr :: VersionConfig a -> Constr # dataTypeOf :: VersionConfig a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (VersionConfig a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (VersionConfig a)) # gmapT :: (forall b. Data b => b -> b) -> VersionConfig a -> VersionConfig a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> VersionConfig a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> VersionConfig a -> r # gmapQ :: (forall d. Data d => d -> u) -> VersionConfig a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> VersionConfig a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> VersionConfig a -> m (VersionConfig a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> VersionConfig a -> m (VersionConfig a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> VersionConfig a -> m (VersionConfig a) #
Generic (VersionConfig a) Source #
Instance details Defined in Data.Store.Version Associated Types type Rep (VersionConfig a) :: Type -> Type # Methods from :: VersionConfig a -> Rep (VersionConfig a) x # to :: Rep (VersionConfig a) x -> VersionConfig a #
Show (VersionConfig a) Source #
Instance details Defined in Data.Store.Version Methods showsPrec :: Int -> VersionConfig a -> ShowS # show :: VersionConfig a -> String # showList :: [VersionConfig a] -> ShowS #
Eq (VersionConfig a) Source #
Instance details Defined in Data.Store.Version Methods (==) :: VersionConfig a -> VersionConfig a -> Bool # (/=) :: VersionConfig a -> VersionConfig a -> Bool #
type Rep (VersionConfig a) Source #
Instance details Defined in Data.Store.Version type Rep (VersionConfig a) = D1 ('MetaData "VersionConfig" "Data.Store.Version" "store-0.7.18-JKaeHVOO5ISLnJjhQgwn0u" 'False) (C1 ('MetaCons "VersionConfig" 'PrefixI 'True) ((S1 ('MetaSel ('Just "vcExpectedHash") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Maybe String)) :: S1 ('MetaSel ('Just "vcManualName") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Maybe String))) :: (S1 ('MetaSel ('Just "vcIgnore") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Set String)) :*: S1 ('MetaSel ('Just "vcRenames") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Map String String)))))

hashedVersionConfig :: String -> VersionConfig a Source #

namedVersionConfig :: String -> String -> VersionConfig a Source #

encodeWithVersionQ :: Data a => VersionConfig a -> Q Exp Source #

decodeWithVersionQ :: Data a => VersionConfig a -> Q Exp Source #