Copyright	(c) 2011 MailRank Inc.
License	Apache
Maintainer	Mark Hibberd <mark@hibberd.id.au>, Nathan Hunter <nhunter@janrain.com>
Stability	experimental
Portability	portable
Safe Haskell	None
Language	Haskell2010

Network.Riak.Resolvable

Description

Storage and retrieval of data with automatic conflict resolution.

Synopsis

class Show a => Resolvable a where
- resolve :: a -> a -> a
newtype ResolvableMonoid a = RM {
- unRM :: a
}
data ResolutionFailure = RetriesExceeded

Documentation

class Show a => Resolvable a where Source #

A type that can automatically resolve a vector clock conflict between two or more versions of a value.

Instances must be symmetric in their behaviour, such that the following law is obeyed:

resolve a b == resolve b a

Otherwise, there are no restrictions on the behaviour of resolve. The result may be a, b, a value derived from a and b, or something else.

If several conflicting siblings are found, resolve will be applied over all of them using a fold, to yield a single "winner".

Methods

resolve :: a -> a -> a Source #

Resolve a conflict between two values.

Instances

Instances details

Resolvable a => Resolvable (Maybe a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods resolve :: Maybe a -> Maybe a -> Maybe a Source #
(Show a, Monoid a) => Resolvable (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods resolve :: ResolvableMonoid a -> ResolvableMonoid a -> ResolvableMonoid a Source #

newtype ResolvableMonoid a Source #

A newtype wrapper that uses the mappend method of a type's Monoid instance to perform vector clock conflict resolution.

Constructors

RM
Fields unRM :: a

Instances

Instances details

Eq a => Eq (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods (==) :: ResolvableMonoid a -> ResolvableMonoid a -> Bool # (/=) :: ResolvableMonoid a -> ResolvableMonoid a -> Bool #
Data a => Data (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ResolvableMonoid a -> c (ResolvableMonoid a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (ResolvableMonoid a) # toConstr :: ResolvableMonoid a -> Constr # dataTypeOf :: ResolvableMonoid a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (ResolvableMonoid a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (ResolvableMonoid a)) # gmapT :: (forall b. Data b => b -> b) -> ResolvableMonoid a -> ResolvableMonoid a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ResolvableMonoid a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ResolvableMonoid a -> r # gmapQ :: (forall d. Data d => d -> u) -> ResolvableMonoid a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> ResolvableMonoid a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> ResolvableMonoid a -> m (ResolvableMonoid a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ResolvableMonoid a -> m (ResolvableMonoid a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ResolvableMonoid a -> m (ResolvableMonoid a) #
Ord a => Ord (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods compare :: ResolvableMonoid a -> ResolvableMonoid a -> Ordering # (<) :: ResolvableMonoid a -> ResolvableMonoid a -> Bool # (<=) :: ResolvableMonoid a -> ResolvableMonoid a -> Bool # (>) :: ResolvableMonoid a -> ResolvableMonoid a -> Bool # (>=) :: ResolvableMonoid a -> ResolvableMonoid a -> Bool # max :: ResolvableMonoid a -> ResolvableMonoid a -> ResolvableMonoid a # min :: ResolvableMonoid a -> ResolvableMonoid a -> ResolvableMonoid a #
Read a => Read (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods readsPrec :: Int -> ReadS (ResolvableMonoid a) # readList :: ReadS [ResolvableMonoid a] # readPrec :: ReadPrec (ResolvableMonoid a) # readListPrec :: ReadPrec [ResolvableMonoid a] #
Show a => Show (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods showsPrec :: Int -> ResolvableMonoid a -> ShowS # show :: ResolvableMonoid a -> String # showList :: [ResolvableMonoid a] -> ShowS #
Semigroup a => Semigroup (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods (<>) :: ResolvableMonoid a -> ResolvableMonoid a -> ResolvableMonoid a # sconcat :: NonEmpty (ResolvableMonoid a) -> ResolvableMonoid a # stimes :: Integral b => b -> ResolvableMonoid a -> ResolvableMonoid a #
Monoid a => Monoid (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods mempty :: ResolvableMonoid a # mappend :: ResolvableMonoid a -> ResolvableMonoid a -> ResolvableMonoid a # mconcat :: [ResolvableMonoid a] -> ResolvableMonoid a #
ToJSON a => ToJSON (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods toJSON :: ResolvableMonoid a -> Value # toEncoding :: ResolvableMonoid a -> Encoding # toJSONList :: [ResolvableMonoid a] -> Value # toEncodingList :: [ResolvableMonoid a] -> Encoding #
FromJSON a => FromJSON (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods parseJSON :: Value -> Parser (ResolvableMonoid a) # parseJSONList :: Value -> Parser [ResolvableMonoid a] #
(Show a, Monoid a) => Resolvable (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods resolve :: ResolvableMonoid a -> ResolvableMonoid a -> ResolvableMonoid a Source #
IsContent a => IsContent (ResolvableMonoid a) Source #
Instance details Defined in Network.Riak.Value Methods parseContent :: RpbContent -> Parser (ResolvableMonoid a) Source # toContent :: ResolvableMonoid a -> RpbContent Source #

data ResolutionFailure Source #

Automated conflict resolution failed.

Constructors

RetriesExceeded

Too many attempts were made to resolve a conflict, with each attempt resulting in another conflict.

The number of retries that the library will attempt is high (64). This makes it extremely unlikely that this exception will be thrown during normal application operation. Instead, this exception is most likely to be thrown as a result of a bug in your application code, for example if your resolve function is misbehaving.

Instances

Instances details

Eq ResolutionFailure Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods (==) :: ResolutionFailure -> ResolutionFailure -> Bool # (/=) :: ResolutionFailure -> ResolutionFailure -> Bool #
Show ResolutionFailure Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods showsPrec :: Int -> ResolutionFailure -> ShowS # show :: ResolutionFailure -> String # showList :: [ResolutionFailure] -> ShowS #
Exception ResolutionFailure Source #
Instance details Defined in Network.Riak.Resolvable.Internal Methods toException :: ResolutionFailure -> SomeException # fromException :: SomeException -> Maybe ResolutionFailure # displayException :: ResolutionFailure -> String #