Safe Haskell	None
Language	Haskell2010

Data.Mergeful.Collection

Contents

Client side
Server side
- The store
- Processing a sync request

Description

A way to synchronise a single item with safe merge conflicts.

The setup is as follows:

A central server is set up to synchronise with
Each client synchronises with the central server, but never with eachother

A client should operate as follows:

The client starts with an initialClientStore.

The client produces a SyncRequest with makeSyncRequest.
The client sends that request to the central server and gets a SyncResponse.
The client then updates its local store with mergeSyncResponseIgnoreProblems.

The central server should operate as follows:

The server starts with an initialServerStore.

The server accepts a SyncRequest.
The server performs operations according to the functionality of processServerSync or processServerSyncCustom.
The server respons with a SyncResponse.

WARNING: This whole approach can break down if a server resets its server times or if a client syncs with two different servers using the same server times.

Synopsis

data ClientStore ci si a = ClientStore {
- clientStoreAddedItems :: Map ci a
- clientStoreSyncedItems :: Map si (Timed a)
- clientStoreSyncedButChangedItems :: Map si (Timed a)
- clientStoreDeletedItems :: Map si ServerTime
}
data Timed a = Timed {
- timedValue :: !a
- timedTime :: !ServerTime
}
newtype ServerTime = ServerTime {
- unServerTime :: Word64
}
initialClientStore :: ClientStore ci si a
clientStoreSize :: ClientStore ci si a -> Word
clientStoreClientIdSet :: ClientStore ci si a -> Set ci
clientStoreUndeletedSyncIdSet :: Ord si => ClientStore ci si a -> Set si
clientStoreSyncIdSet :: Ord si => ClientStore ci si a -> Set si
clientStoreItems :: (Ord ci, Ord si) => ClientStore ci si a -> Map (Either ci si) a
addItemToClientStore :: (Ord ci, Enum ci, Bounded ci) => a -> ClientStore ci si a -> ClientStore ci si a
findFreeSpot :: (Ord ci, Enum ci, Bounded ci) => Map ci a -> ci
markItemDeletedInClientStore :: Ord si => si -> ClientStore ci si a -> ClientStore ci si a
changeItemInClientStore :: Ord si => si -> a -> ClientStore ci si a -> ClientStore ci si a
deleteItemFromClientStore :: Ord ci => ci -> ClientStore ci si a -> ClientStore ci si a
data SyncRequest ci si a = SyncRequest {
- syncRequestNewItems :: !(Map ci a)
- syncRequestKnownItems :: !(Map si ServerTime)
- syncRequestKnownButChangedItems :: !(Map si (Timed a))
- syncRequestDeletedItems :: !(Map si ServerTime)
}
initialSyncRequest :: SyncRequest ci si a
makeSyncRequest :: ClientStore ci si a -> SyncRequest ci si a
data SyncResponse ci si a = SyncResponse {
- syncResponseClientAdded :: !(Map ci (ClientAddition si))
- syncResponseClientChanged :: !(Map si ServerTime)
- syncResponseClientDeleted :: !(Set si)
- syncResponseServerAdded :: !(Map si (Timed a))
- syncResponseServerChanged :: !(Map si (Timed a))
- syncResponseServerDeleted :: !(Set si)
- syncResponseConflicts :: !(Map si (Timed a))
- syncResponseConflictsClientDeleted :: !(Map si (Timed a))
- syncResponseConflictsServerDeleted :: !(Set si)
}
data ClientAddition i = ClientAddition {
- clientAdditionId :: i
- clientAdditionServerTime :: ServerTime
}
data ItemMergeStrategy a = ItemMergeStrategy {
- itemMergeStrategyMergeChangeConflict :: a -> a -> ChangeConflictResolution a
- itemMergeStrategyMergeClientDeletedConflict :: a -> ClientDeletedConflictResolution
- itemMergeStrategyMergeServerDeletedConflict :: a -> ServerDeletedConflictResolution
}
data ChangeConflictResolution a
- = KeepLocal
- | TakeRemote
- | Merged a
data ClientDeletedConflictResolution
- = TakeRemoteChange
- | StayDeleted
data ServerDeletedConflictResolution
- = KeepLocalChange
- | Delete
mergeFromServerStrategy :: ItemMergeStrategy a
mergeFromClientStrategy :: ItemMergeStrategy a
mergeUsingCRDTStrategy :: (a -> a -> a) -> ItemMergeStrategy a
mergeSyncResponseFromServer :: (Ord ci, Ord si) => ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a
mergeSyncResponseFromClient :: (Ord ci, Ord si) => ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a
mergeSyncResponseUsingCRDT :: (Ord ci, Ord si) => (a -> a -> a) -> ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a
mergeSyncResponseUsingStrategy :: (Ord ci, Ord si) => ItemMergeStrategy a -> ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a
data ClientSyncProcessor ci si a (m :: * -> *) = ClientSyncProcessor {
- clientSyncProcessorQuerySyncedButChangedValues :: !(Set si -> m (Map si (Timed a)))
- clientSyncProcessorSyncClientAdded :: !(Map ci (ClientAddition si) -> m ())
- clientSyncProcessorSyncClientChanged :: !(Map si ServerTime -> m ())
- clientSyncProcessorSyncClientDeleted :: !(Set si -> m ())
- clientSyncProcessorSyncMergedConflict :: !(Map si (Timed a) -> m ())
- clientSyncProcessorSyncServerAdded :: !(Map si (Timed a) -> m ())
- clientSyncProcessorSyncServerChanged :: !(Map si (Timed a) -> m ())
- clientSyncProcessorSyncServerDeleted :: !(Set si -> m ())
}
mergeSyncResponseCustom :: (Ord si, Monad m) => ItemMergeStrategy a -> ClientSyncProcessor ci si a m -> SyncResponse ci si a -> m ()
newtype ClientId = ClientId {
- unClientId :: Word64
}
mergeAddedItems :: forall ci si a. (Ord ci, Ord si) => Map ci a -> Map ci (ClientAddition si) -> (Map ci a, Map si (Timed a))
mergeSyncedButChangedItems :: forall i a. Ord i => Map i (Timed a) -> Map i ServerTime -> (Map i (Timed a), Map i (Timed a))
mergeDeletedItems :: Ord i => Map i b -> Set i -> Map i b
mergeSyncedButChangedConflicts :: forall si a. Ord si => (a -> a -> ChangeConflictResolution a) -> Map si (Timed a) -> Map si (Timed a) -> (Map si (Timed a), Map si (Timed a), Map si (Timed a))
mergeClientDeletedConflicts :: (a -> ClientDeletedConflictResolution) -> Map si (Timed a) -> Map si (Timed a)
mergeServerDeletedConflicts :: (a -> ServerDeletedConflictResolution) -> Map si (Timed a) -> Set si
newtype ServerStore si a = ServerStore {
- serverStoreItems :: Map si (Timed a)
}
initialServerStore :: ServerStore si a
processServerSync :: forall ci si a m. (Ord si, Monad m) => m si -> ServerStore si a -> SyncRequest ci si a -> m (SyncResponse ci si a, ServerStore si a)
data ServerSyncProcessor ci si a m = ServerSyncProcessor {
- serverSyncProcessorRead :: !(m (Map si (Timed a)))
- serverSyncProcessorAddItem :: !(a -> m si)
- serverSyncProcessorChangeItem :: !(si -> ServerTime -> a -> m ())
- serverSyncProcessorDeleteItem :: !(si -> m ())
}
processServerSyncCustom :: forall ci si a m. (Ord si, Monad m) => ServerSyncProcessor ci si a m -> SyncRequest ci si a -> m (SyncResponse ci si a)
emptySyncResponse :: SyncResponse ci si a
initialServerTime :: ServerTime
incrementServerTime :: ServerTime -> ServerTime

Client side

data ClientStore ci si a Source #

Constructors

ClientStore

Fields

clientStoreAddedItems :: Map ci a
These items are new locally but have not been synced to the server yet.
clientStoreSyncedItems :: Map si (Timed a)
These items have been synced at their respective ServerTimes.
clientStoreSyncedButChangedItems :: Map si (Timed a)
These items have been synced at their respective ServerTimes but modified locally since then.
clientStoreDeletedItems :: Map si ServerTime
These items have been deleted locally after they were synced but the server has not been notified of that yet.

Instances

(Eq ci, Eq a, Eq si) => Eq (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods (==) :: ClientStore ci si a -> ClientStore ci si a -> Bool # (/=) :: ClientStore ci si a -> ClientStore ci si a -> Bool #
(Show ci, Show a, Show si) => Show (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods showsPrec :: Int -> ClientStore ci si a -> ShowS # show :: ClientStore ci si a -> String # showList :: [ClientStore ci si a] -> ShowS #
Generic (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (ClientStore ci si a) :: Type -> Type # Methods from :: ClientStore ci si a -> Rep (ClientStore ci si a) x # to :: Rep (ClientStore ci si a) x -> ClientStore ci si a #
(ToJSONKey ci, ToJSONKey si, ToJSON a) => ToJSON (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSON :: ClientStore ci si a -> Value # toEncoding :: ClientStore ci si a -> Encoding # toJSONList :: [ClientStore ci si a] -> Value # toEncodingList :: [ClientStore ci si a] -> Encoding #
(Ord ci, Ord si, FromJSONKey ci, FromJSONKey si, FromJSON a) => FromJSON (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods parseJSON :: Value -> Parser (ClientStore ci si a) # parseJSONList :: Value -> Parser [ClientStore ci si a] #
(NFData ci, NFData si, NFData a) => NFData (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods rnf :: ClientStore ci si a -> () #
(Validity ci, Validity si, Show ci, Show si, Ord ci, Ord si, Validity a) => Validity (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods validate :: ClientStore ci si a -> Validation #
type Rep (ClientStore ci si a) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (ClientStore ci si a) = D1 (MetaData "ClientStore" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "ClientStore" PrefixI True) ((S1 (MetaSel (Just "clientStoreAddedItems") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Map ci a)) :: S1 (MetaSel (Just "clientStoreSyncedItems") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Map si (Timed a)))) :: (S1 (MetaSel (Just "clientStoreSyncedButChangedItems") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Map si (Timed a))) :*: S1 (MetaSel (Just "clientStoreDeletedItems") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Map si ServerTime)))))

data Timed a Source #

A value along with a server time.

Constructors

Timed
Fields timedValue :: !a timedTime :: !ServerTime

Instances

Eq a => Eq (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Methods (==) :: Timed a -> Timed a -> Bool # (/=) :: Timed a -> Timed a -> Bool #
Show a => Show (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Methods showsPrec :: Int -> Timed a -> ShowS # show :: Timed a -> String # showList :: [Timed a] -> ShowS #
Generic (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Associated Types type Rep (Timed a) :: Type -> Type # Methods from :: Timed a -> Rep (Timed a) x # to :: Rep (Timed a) x -> Timed a #
ToJSON a => ToJSON (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Methods toJSON :: Timed a -> Value # toEncoding :: Timed a -> Encoding # toJSONList :: [Timed a] -> Value # toEncodingList :: [Timed a] -> Encoding #
FromJSON a => FromJSON (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Methods parseJSON :: Value -> Parser (Timed a) # parseJSONList :: Value -> Parser [Timed a] #
NFData a => NFData (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Methods rnf :: Timed a -> () #
Validity a => Validity (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed Methods validate :: Timed a -> Validation #
type Rep (Timed a) Source #
Instance details Defined in Data.Mergeful.Timed type Rep (Timed a) = D1 (MetaData "Timed" "Data.Mergeful.Timed" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "Timed" PrefixI True) (S1 (MetaSel (Just "timedValue") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 a) :*: S1 (MetaSel (Just "timedTime") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 ServerTime)))

newtype ServerTime Source #

A "time", as "measured" by the server.

This is closer to a version number than an actual timestamp, but that distinction should not matter for your usage of this library.

In any case, a client should not be changing this value.

We use a Word64 instead of a natural. This will go wrong after 2^64 versions, but since that will not happen in practice, we will not worry about it. You would have to sync millions of modifications every second until long after the sun consumes the earth for this to be a problem.

Constructors

ServerTime
Fields unServerTime :: Word64

Instances

Eq ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods (==) :: ServerTime -> ServerTime -> Bool # (/=) :: ServerTime -> ServerTime -> Bool #
Ord ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods compare :: ServerTime -> ServerTime -> Ordering # (<) :: ServerTime -> ServerTime -> Bool # (<=) :: ServerTime -> ServerTime -> Bool # (>) :: ServerTime -> ServerTime -> Bool # (>=) :: ServerTime -> ServerTime -> Bool # max :: ServerTime -> ServerTime -> ServerTime # min :: ServerTime -> ServerTime -> ServerTime #
Show ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods showsPrec :: Int -> ServerTime -> ShowS # show :: ServerTime -> String # showList :: [ServerTime] -> ShowS #
Generic ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Associated Types type Rep ServerTime :: Type -> Type # Methods from :: ServerTime -> Rep ServerTime x # to :: Rep ServerTime x -> ServerTime #
ToJSON ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods toJSON :: ServerTime -> Value # toEncoding :: ServerTime -> Encoding # toJSONList :: [ServerTime] -> Value # toEncodingList :: [ServerTime] -> Encoding #
FromJSON ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods parseJSON :: Value -> Parser ServerTime # parseJSONList :: Value -> Parser [ServerTime] #
NFData ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods rnf :: ServerTime -> () #
Validity ServerTime Source #
Instance details Defined in Data.Mergeful.Timed Methods validate :: ServerTime -> Validation #
type Rep ServerTime Source #
Instance details Defined in Data.Mergeful.Timed type Rep ServerTime = D1 (MetaData "ServerTime" "Data.Mergeful.Timed" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" True) (C1 (MetaCons "ServerTime" PrefixI True) (S1 (MetaSel (Just "unServerTime") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Word64)))

initialClientStore :: ClientStore ci si a Source #

A client store to start with.

This store contains no items.

Querying the client store

clientStoreSize :: ClientStore ci si a -> Word Source #

The number of items in a client store

This does not count the deleted items, so that they really look deleted..

clientStoreClientIdSet :: ClientStore ci si a -> Set ci Source #

The set of client ids.

These are only the client ids of the added items that have not been synced yet.

clientStoreUndeletedSyncIdSet :: Ord si => ClientStore ci si a -> Set si Source #

The set of server ids.

This does not include the ids of items that have been marked as deleted.

clientStoreSyncIdSet :: Ord si => ClientStore ci si a -> Set si Source #

The set of server ids.

This includes the ids of items that have been marked as deleted.

clientStoreItems :: (Ord ci, Ord si) => ClientStore ci si a -> Map (Either ci si) a Source #

The set of items in the client store

This map does not include items that have been marked as deleted.

Changing the client store

addItemToClientStore :: (Ord ci, Enum ci, Bounded ci) => a -> ClientStore ci si a -> ClientStore ci si a Source #

Add an item to a client store as an added item.

This will take care of the uniqueness constraint of the cis in the map.

findFreeSpot :: (Ord ci, Enum ci, Bounded ci) => Map ci a -> ci Source #

Find a free client id to use

You shouldn't need this function, addItemToClientStore takes care of this.

The values wrap around when reaching maxBound.

markItemDeletedInClientStore :: Ord si => si -> ClientStore ci si a -> ClientStore ci si a Source #

Mark an item deleted in a client store.

This function will not delete the item, but mark it as deleted instead.

changeItemInClientStore :: Ord si => si -> a -> ClientStore ci si a -> ClientStore ci si a Source #

Replace the given item with a new value.

This function will correctly mark the item as changed, if it exist.

It will not add an item to the store with the given id, because the server may not have been the origin of that id.

deleteItemFromClientStore :: Ord ci => ci -> ClientStore ci si a -> ClientStore ci si a Source #

Delete an unsynced item from a client store.

This function will immediately delete the item, because it has never been synced.

Maxing a sync request

data SyncRequest ci si a Source #

Constructors

SyncRequest

Fields

syncRequestNewItems :: !(Map ci a)
These items are new locally but have not been synced to the server yet.
syncRequestKnownItems :: !(Map si ServerTime)
These items have been synced at their respective ServerTimes.
syncRequestKnownButChangedItems :: !(Map si (Timed a))
These items have been synced at their respective ServerTimes but modified locally since then.
syncRequestDeletedItems :: !(Map si ServerTime)
These items have been deleted locally after they were synced but the server has not been notified of that yet.

Instances

(Eq ci, Eq a, Eq si) => Eq (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods (==) :: SyncRequest ci si a -> SyncRequest ci si a -> Bool # (/=) :: SyncRequest ci si a -> SyncRequest ci si a -> Bool #
(Show ci, Show a, Show si) => Show (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods showsPrec :: Int -> SyncRequest ci si a -> ShowS # show :: SyncRequest ci si a -> String # showList :: [SyncRequest ci si a] -> ShowS #
Generic (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (SyncRequest ci si a) :: Type -> Type # Methods from :: SyncRequest ci si a -> Rep (SyncRequest ci si a) x # to :: Rep (SyncRequest ci si a) x -> SyncRequest ci si a #
(ToJSONKey ci, ToJSONKey si, ToJSON a) => ToJSON (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSON :: SyncRequest ci si a -> Value # toEncoding :: SyncRequest ci si a -> Encoding # toJSONList :: [SyncRequest ci si a] -> Value # toEncodingList :: [SyncRequest ci si a] -> Encoding #
(Ord ci, Ord si, FromJSONKey ci, FromJSONKey si, FromJSON a) => FromJSON (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods parseJSON :: Value -> Parser (SyncRequest ci si a) # parseJSONList :: Value -> Parser [SyncRequest ci si a] #
(NFData ci, NFData si, NFData a) => NFData (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods rnf :: SyncRequest ci si a -> () #
(Validity ci, Validity si, Show ci, Show si, Ord ci, Ord si, Validity a) => Validity (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods validate :: SyncRequest ci si a -> Validation #
type Rep (SyncRequest ci si a) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (SyncRequest ci si a) = D1 (MetaData "SyncRequest" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "SyncRequest" PrefixI True) ((S1 (MetaSel (Just "syncRequestNewItems") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map ci a)) :: S1 (MetaSel (Just "syncRequestKnownItems") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si ServerTime))) :: (S1 (MetaSel (Just "syncRequestKnownButChangedItems") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a))) :*: S1 (MetaSel (Just "syncRequestDeletedItems") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si ServerTime)))))

initialSyncRequest :: SyncRequest ci si a Source #

An intial SyncRequest to start with.

It just asks the server to send over whatever it knows.

makeSyncRequest :: ClientStore ci si a -> SyncRequest ci si a Source #

Produce an SyncRequest from a ClientStore.

Send this to the server for synchronisation.

Merging the response

data SyncResponse ci si a Source #

Constructors

SyncResponse

Fields

syncResponseClientAdded :: !(Map ci (ClientAddition si))
The client added these items and server has succesfully been made aware of that.
The client needs to update their server times
syncResponseClientChanged :: !(Map si ServerTime)
The client changed these items and server has succesfully been made aware of that.
The client needs to update their server times
syncResponseClientDeleted :: !(Set si)
The client deleted these items and server has succesfully been made aware of that.
The client can delete them from its deleted items
syncResponseServerAdded :: !(Map si (Timed a))
These items have been added on the server side
The client should add them too.
syncResponseServerChanged :: !(Map si (Timed a))
These items have been modified on the server side.
The client should modify them too.
syncResponseServerDeleted :: !(Set si)
These items were deleted on the server side
The client should delete them too
syncResponseConflicts :: !(Map si (Timed a))
These are conflicts where the server and the client both have an item, but it is different.
The server kept its part of each, the client can either take whatever the server gave them or deal with the conflicts somehow, and then try to re-sync.
syncResponseConflictsClientDeleted :: !(Map si (Timed a))
These are conflicts where the server has an item but the client does not.
The server kept its item, the client can either take whatever the server gave them or deal with the conflicts somehow, and then try to re-sync.
syncResponseConflictsServerDeleted :: !(Set si)
These are conflicts where the server has no item but the client has a modified item.
The server left its item deleted, the client can either delete its items too or deal with the conflicts somehow, and then try to re-sync.

Instances

(Eq ci, Eq si, Eq a) => Eq (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods (==) :: SyncResponse ci si a -> SyncResponse ci si a -> Bool # (/=) :: SyncResponse ci si a -> SyncResponse ci si a -> Bool #
(Show ci, Show si, Show a) => Show (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods showsPrec :: Int -> SyncResponse ci si a -> ShowS # show :: SyncResponse ci si a -> String # showList :: [SyncResponse ci si a] -> ShowS #
Generic (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (SyncResponse ci si a) :: Type -> Type # Methods from :: SyncResponse ci si a -> Rep (SyncResponse ci si a) x # to :: Rep (SyncResponse ci si a) x -> SyncResponse ci si a #
(ToJSON ci, ToJSON si, ToJSONKey ci, ToJSONKey si, ToJSON a) => ToJSON (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSON :: SyncResponse ci si a -> Value # toEncoding :: SyncResponse ci si a -> Encoding # toJSONList :: [SyncResponse ci si a] -> Value # toEncodingList :: [SyncResponse ci si a] -> Encoding #
(Ord ci, Ord si, FromJSON ci, FromJSON si, FromJSONKey ci, FromJSONKey si, FromJSON a) => FromJSON (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods parseJSON :: Value -> Parser (SyncResponse ci si a) # parseJSONList :: Value -> Parser [SyncResponse ci si a] #
(NFData ci, NFData si, NFData a) => NFData (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods rnf :: SyncResponse ci si a -> () #
(Validity ci, Validity si, Show ci, Show si, Ord ci, Ord si, Validity a) => Validity (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods validate :: SyncResponse ci si a -> Validation #
type Rep (SyncResponse ci si a) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (SyncResponse ci si a) = D1 (MetaData "SyncResponse" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "SyncResponse" PrefixI True) (((S1 (MetaSel (Just "syncResponseClientAdded") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map ci (ClientAddition si))) :: S1 (MetaSel (Just "syncResponseClientChanged") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si ServerTime))) :: (S1 (MetaSel (Just "syncResponseClientDeleted") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Set si)) :: S1 (MetaSel (Just "syncResponseServerAdded") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a))))) :: ((S1 (MetaSel (Just "syncResponseServerChanged") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a))) :: S1 (MetaSel (Just "syncResponseServerDeleted") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Set si))) :: (S1 (MetaSel (Just "syncResponseConflicts") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a))) :: (S1 (MetaSel (Just "syncResponseConflictsClientDeleted") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a))) :: S1 (MetaSel (Just "syncResponseConflictsServerDeleted") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Set si)))))))

data ClientAddition i Source #

Constructors

ClientAddition
Fields clientAdditionId :: i clientAdditionServerTime :: ServerTime

Instances

Eq i => Eq (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Methods (==) :: ClientAddition i -> ClientAddition i -> Bool # (/=) :: ClientAddition i -> ClientAddition i -> Bool #
Show i => Show (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Methods showsPrec :: Int -> ClientAddition i -> ShowS # show :: ClientAddition i -> String # showList :: [ClientAddition i] -> ShowS #
Generic (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (ClientAddition i) :: Type -> Type # Methods from :: ClientAddition i -> Rep (ClientAddition i) x # to :: Rep (ClientAddition i) x -> ClientAddition i #
ToJSON i => ToJSON (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSON :: ClientAddition i -> Value # toEncoding :: ClientAddition i -> Encoding # toJSONList :: [ClientAddition i] -> Value # toEncodingList :: [ClientAddition i] -> Encoding #
FromJSON i => FromJSON (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Methods parseJSON :: Value -> Parser (ClientAddition i) # parseJSONList :: Value -> Parser [ClientAddition i] #
NFData i => NFData (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Methods rnf :: ClientAddition i -> () #
Validity i => Validity (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection Methods validate :: ClientAddition i -> Validation #
type Rep (ClientAddition i) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (ClientAddition i) = D1 (MetaData "ClientAddition" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "ClientAddition" PrefixI True) (S1 (MetaSel (Just "clientAdditionId") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 i) :*: S1 (MetaSel (Just "clientAdditionServerTime") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 ServerTime)))

data ItemMergeStrategy a Source #

A strategy to merge conflicts for item synchronisation

Constructors

ItemMergeStrategy

Fields

itemMergeStrategyMergeChangeConflict :: a -> a -> ChangeConflictResolution a
How to merge modification conflicts
The first argument is the client item and the second argument is the server item.
itemMergeStrategyMergeClientDeletedConflict :: a -> ClientDeletedConflictResolution
How to merge conflicts where the client deleted an item that the server modified
itemMergeStrategyMergeServerDeletedConflict :: a -> ServerDeletedConflictResolution
How to merge conflicts where the server deleted an item that the client modified

Instances

Generic (ItemMergeStrategy a) Source #
Instance details Defined in Data.Mergeful.Item Associated Types type Rep (ItemMergeStrategy a) :: Type -> Type # Methods from :: ItemMergeStrategy a -> Rep (ItemMergeStrategy a) x # to :: Rep (ItemMergeStrategy a) x -> ItemMergeStrategy a #
type Rep (ItemMergeStrategy a) Source #
Instance details Defined in Data.Mergeful.Item type Rep (ItemMergeStrategy a) = D1 (MetaData "ItemMergeStrategy" "Data.Mergeful.Item" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "ItemMergeStrategy" PrefixI True) (S1 (MetaSel (Just "itemMergeStrategyMergeChangeConflict") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (a -> a -> ChangeConflictResolution a)) :: (S1 (MetaSel (Just "itemMergeStrategyMergeClientDeletedConflict") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (a -> ClientDeletedConflictResolution)) :: S1 (MetaSel (Just "itemMergeStrategyMergeServerDeletedConflict") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (a -> ServerDeletedConflictResolution)))))

data ChangeConflictResolution a Source #

Constructors

KeepLocal
TakeRemote
Merged a

Instances

Eq a => Eq (ChangeConflictResolution a) Source #
Instance details Defined in Data.Mergeful.Item Methods (==) :: ChangeConflictResolution a -> ChangeConflictResolution a -> Bool # (/=) :: ChangeConflictResolution a -> ChangeConflictResolution a -> Bool #
Show a => Show (ChangeConflictResolution a) Source #
Instance details Defined in Data.Mergeful.Item Methods showsPrec :: Int -> ChangeConflictResolution a -> ShowS # show :: ChangeConflictResolution a -> String # showList :: [ChangeConflictResolution a] -> ShowS #
Generic (ChangeConflictResolution a) Source #
Instance details Defined in Data.Mergeful.Item Associated Types type Rep (ChangeConflictResolution a) :: Type -> Type # Methods from :: ChangeConflictResolution a -> Rep (ChangeConflictResolution a) x # to :: Rep (ChangeConflictResolution a) x -> ChangeConflictResolution a #
type Rep (ChangeConflictResolution a) Source #
Instance details Defined in Data.Mergeful.Item type Rep (ChangeConflictResolution a) = D1 (MetaData "ChangeConflictResolution" "Data.Mergeful.Item" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "KeepLocal" PrefixI False) (U1 :: Type -> Type) :+: (C1 (MetaCons "TakeRemote" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "Merged" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a))))

data ClientDeletedConflictResolution Source #

Constructors

TakeRemoteChange
StayDeleted

Instances

Eq ClientDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item Methods (==) :: ClientDeletedConflictResolution -> ClientDeletedConflictResolution -> Bool # (/=) :: ClientDeletedConflictResolution -> ClientDeletedConflictResolution -> Bool #
Show ClientDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item Methods showsPrec :: Int -> ClientDeletedConflictResolution -> ShowS # show :: ClientDeletedConflictResolution -> String # showList :: [ClientDeletedConflictResolution] -> ShowS #
Generic ClientDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item Associated Types type Rep ClientDeletedConflictResolution :: Type -> Type # Methods from :: ClientDeletedConflictResolution -> Rep ClientDeletedConflictResolution x # to :: Rep ClientDeletedConflictResolution x -> ClientDeletedConflictResolution #
type Rep ClientDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item type Rep ClientDeletedConflictResolution = D1 (MetaData "ClientDeletedConflictResolution" "Data.Mergeful.Item" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "TakeRemoteChange" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "StayDeleted" PrefixI False) (U1 :: Type -> Type))

data ServerDeletedConflictResolution Source #

Constructors

KeepLocalChange
Delete

Instances

Eq ServerDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item Methods (==) :: ServerDeletedConflictResolution -> ServerDeletedConflictResolution -> Bool # (/=) :: ServerDeletedConflictResolution -> ServerDeletedConflictResolution -> Bool #
Show ServerDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item Methods showsPrec :: Int -> ServerDeletedConflictResolution -> ShowS # show :: ServerDeletedConflictResolution -> String # showList :: [ServerDeletedConflictResolution] -> ShowS #
Generic ServerDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item Associated Types type Rep ServerDeletedConflictResolution :: Type -> Type # Methods from :: ServerDeletedConflictResolution -> Rep ServerDeletedConflictResolution x # to :: Rep ServerDeletedConflictResolution x -> ServerDeletedConflictResolution #
type Rep ServerDeletedConflictResolution Source #
Instance details Defined in Data.Mergeful.Item type Rep ServerDeletedConflictResolution = D1 (MetaData "ServerDeletedConflictResolution" "Data.Mergeful.Item" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "KeepLocalChange" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "Delete" PrefixI False) (U1 :: Type -> Type))

mergeFromServerStrategy :: ItemMergeStrategy a Source #

A merge strategy that takes whatever the server gave the client.

Pro: Clients will converge on the same value.

Con: Conflicting updates will be lost.

mergeFromClientStrategy :: ItemMergeStrategy a Source #

A merge strategy that keeps whatever the client had.

Pro: does not lose data

Con: Clients will diverge when a conflict occurs

mergeUsingCRDTStrategy :: (a -> a -> a) -> ItemMergeStrategy a Source #

A merge strategy that uses a CRDT merging function to merge items.

In case of other-than-change conflicts, this will be the same as the mergeFromServerStrategy strategy. If this is not what you want, create your own ItemMergeStrategy manually.

mergeSyncResponseFromServer :: (Ord ci, Ord si) => ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a Source #

Merge a SyncResponse into the current ClientStore by taking whatever the server gave the client in case of conflict.

Pro: Clients will converge on the same value.

Con: Conflicting updates will be lost.

mergeSyncResponseFromClient :: (Ord ci, Ord si) => ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a Source #

Merge a SyncResponse into the current ClientStore by keeping whatever the client had in case of conflict.

Pro: No data will be lost

Con: Clients will diverge when conflicts occur.

mergeSyncResponseUsingCRDT :: (Ord ci, Ord si) => (a -> a -> a) -> ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a Source #

Merge a SyncResponse into the current ClientStore by using the given GADT merging function in case of conflict

mergeSyncResponseUsingStrategy :: (Ord ci, Ord si) => ItemMergeStrategy a -> ClientStore ci si a -> SyncResponse ci si a -> ClientStore ci si a Source #

Merge an SyncResponse into the current ClientStore with the given merge strategy.

In order for clients to converge on the same collection correctly, this function must be:

Associative
Idempotent
The same on all clients

This function ignores mismatches.

data ClientSyncProcessor ci si a (m :: * -> *) Source #

Constructors

ClientSyncProcessor

Fields

clientSyncProcessorQuerySyncedButChangedValues :: !(Set si -> m (Map si (Timed a)))
Get the synced values with keys in the given set
clientSyncProcessorSyncClientAdded :: !(Map ci (ClientAddition si) -> m ())
Complete additions that were acknowledged by the server. This involves saving the server id and the server time
clientSyncProcessorSyncClientChanged :: !(Map si ServerTime -> m ())
Complete changes that were acknowledged by the server This involves updating the server time
clientSyncProcessorSyncClientDeleted :: !(Set si -> m ())
Complete deletions that were acknowledged by the server This means deleting these tombstoned items entirely
clientSyncProcessorSyncMergedConflict :: !(Map si (Timed a) -> m ())
Store the items that were in a conflict but the conflict was resolved correctly. These items should be marked as changed.
clientSyncProcessorSyncServerAdded :: !(Map si (Timed a) -> m ())
clientSyncProcessorSyncServerChanged :: !(Map si (Timed a) -> m ())
clientSyncProcessorSyncServerDeleted :: !(Set si -> m ())

Instances

Generic (ClientSyncProcessor ci si a m) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (ClientSyncProcessor ci si a m) :: Type -> Type # Methods from :: ClientSyncProcessor ci si a m -> Rep (ClientSyncProcessor ci si a m) x # to :: Rep (ClientSyncProcessor ci si a m) x -> ClientSyncProcessor ci si a m #
type Rep (ClientSyncProcessor ci si a m) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (ClientSyncProcessor ci si a m) = D1 (MetaData "ClientSyncProcessor" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "ClientSyncProcessor" PrefixI True) (((S1 (MetaSel (Just "clientSyncProcessorQuerySyncedButChangedValues") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Set si -> m (Map si (Timed a)))) :: S1 (MetaSel (Just "clientSyncProcessorSyncClientAdded") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map ci (ClientAddition si) -> m ()))) :: (S1 (MetaSel (Just "clientSyncProcessorSyncClientChanged") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si ServerTime -> m ())) :: S1 (MetaSel (Just "clientSyncProcessorSyncClientDeleted") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Set si -> m ())))) :: ((S1 (MetaSel (Just "clientSyncProcessorSyncMergedConflict") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a) -> m ())) :: S1 (MetaSel (Just "clientSyncProcessorSyncServerAdded") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a) -> m ()))) :: (S1 (MetaSel (Just "clientSyncProcessorSyncServerChanged") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Map si (Timed a) -> m ())) :*: S1 (MetaSel (Just "clientSyncProcessorSyncServerDeleted") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Set si -> m ()))))))

mergeSyncResponseCustom :: (Ord si, Monad m) => ItemMergeStrategy a -> ClientSyncProcessor ci si a m -> SyncResponse ci si a -> m () Source #

Utility functions for implementing pure client-side merging

newtype ClientId Source #

A Client-side identifier for items.

These only need to be unique at the client.

Constructors

ClientId
Fields unClientId :: Word64

Instances

Bounded ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods minBound :: ClientId # maxBound :: ClientId #
Enum ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods succ :: ClientId -> ClientId # pred :: ClientId -> ClientId # toEnum :: Int -> ClientId # fromEnum :: ClientId -> Int # enumFrom :: ClientId -> [ClientId] # enumFromThen :: ClientId -> ClientId -> [ClientId] # enumFromTo :: ClientId -> ClientId -> [ClientId] # enumFromThenTo :: ClientId -> ClientId -> ClientId -> [ClientId] #
Eq ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods (==) :: ClientId -> ClientId -> Bool # (/=) :: ClientId -> ClientId -> Bool #
Ord ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods compare :: ClientId -> ClientId -> Ordering # (<) :: ClientId -> ClientId -> Bool # (<=) :: ClientId -> ClientId -> Bool # (>) :: ClientId -> ClientId -> Bool # (>=) :: ClientId -> ClientId -> Bool # max :: ClientId -> ClientId -> ClientId # min :: ClientId -> ClientId -> ClientId #
Show ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods showsPrec :: Int -> ClientId -> ShowS # show :: ClientId -> String # showList :: [ClientId] -> ShowS #
Generic ClientId Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep ClientId :: Type -> Type # Methods from :: ClientId -> Rep ClientId x # to :: Rep ClientId x -> ClientId #
ToJSON ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSON :: ClientId -> Value # toEncoding :: ClientId -> Encoding # toJSONList :: [ClientId] -> Value # toEncodingList :: [ClientId] -> Encoding #
ToJSONKey ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSONKey :: ToJSONKeyFunction ClientId # toJSONKeyList :: ToJSONKeyFunction [ClientId] #
FromJSON ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods parseJSON :: Value -> Parser ClientId # parseJSONList :: Value -> Parser [ClientId] #
FromJSONKey ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods fromJSONKey :: FromJSONKeyFunction ClientId # fromJSONKeyList :: FromJSONKeyFunction [ClientId] #
NFData ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods rnf :: ClientId -> () #
Validity ClientId Source #
Instance details Defined in Data.Mergeful.Collection Methods validate :: ClientId -> Validation #
type Rep ClientId Source #
Instance details Defined in Data.Mergeful.Collection type Rep ClientId = D1 (MetaData "ClientId" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" True) (C1 (MetaCons "ClientId" PrefixI True) (S1 (MetaSel (Just "unClientId") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Word64)))

mergeAddedItems :: forall ci si a. (Ord ci, Ord si) => Map ci a -> Map ci (ClientAddition si) -> (Map ci a, Map si (Timed a)) Source #

Merge the local added items with the ones that the server has acknowledged as added.

mergeSyncedButChangedItems :: forall i a. Ord i => Map i (Timed a) -> Map i ServerTime -> (Map i (Timed a), Map i (Timed a)) Source #

Merge the local synced but changed items with the ones that the server has acknowledged as changed.

mergeDeletedItems :: Ord i => Map i b -> Set i -> Map i b Source #

Merge the local deleted items with the ones that the server has acknowledged as deleted.

Utility functions for implementing custom client-side merging

mergeSyncedButChangedConflicts Source #

Arguments

:: Ord si
=> (a -> a -> ChangeConflictResolution a)
-> Map si (Timed a)	The conflicting items on the client side
-> Map si (Timed a)	The conflicting items on the server side
-> (Map si (Timed a), Map si (Timed a), Map si (Timed a))	Unresolved conflicts on the left, merged conflicts in the middle, resolved conflicts on the right The unresolved conflicts should remain as-is The merged conflicts should be updated and marked as changed The resolved conflicts should be updated and marked as unchanged

Resolve change conflicts

mergeClientDeletedConflicts Source #

Arguments

:: (a -> ClientDeletedConflictResolution)
-> Map si (Timed a)	The conflicting items on the server side
-> Map si (Timed a)	A map of items that need to be updated on the client.

Resolve client deleted conflicts

mergeServerDeletedConflicts Source #

Arguments

:: (a -> ServerDeletedConflictResolution)
-> Map si (Timed a)	The conflicting items on the client side
-> Set si	The result is a map of items that need to be deleted on the client.

Resolve server deleted conflicts

Server side

The store

newtype ServerStore si a Source #

Constructors

ServerStore
Fields serverStoreItems :: Map si (Timed a) A map of items, named using an `si`, together with the `ServerTime` at which they were last synced.

Instances

(Eq si, Eq a) => Eq (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods (==) :: ServerStore si a -> ServerStore si a -> Bool # (/=) :: ServerStore si a -> ServerStore si a -> Bool #
(Show si, Show a) => Show (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods showsPrec :: Int -> ServerStore si a -> ShowS # show :: ServerStore si a -> String # showList :: [ServerStore si a] -> ShowS #
Generic (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (ServerStore si a) :: Type -> Type # Methods from :: ServerStore si a -> Rep (ServerStore si a) x # to :: Rep (ServerStore si a) x -> ServerStore si a #
(ToJSON a, ToJSONKey si) => ToJSON (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods toJSON :: ServerStore si a -> Value # toEncoding :: ServerStore si a -> Encoding # toJSONList :: [ServerStore si a] -> Value # toEncodingList :: [ServerStore si a] -> Encoding #
(FromJSONKey si, Ord si, FromJSON a) => FromJSON (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods parseJSON :: Value -> Parser (ServerStore si a) # parseJSONList :: Value -> Parser [ServerStore si a] #
(NFData si, NFData a) => NFData (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods rnf :: ServerStore si a -> () #
(Validity si, Show si, Ord si, Validity a) => Validity (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection Methods validate :: ServerStore si a -> Validation #
type Rep (ServerStore si a) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (ServerStore si a) = D1 (MetaData "ServerStore" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" True) (C1 (MetaCons "ServerStore" PrefixI True) (S1 (MetaSel (Just "serverStoreItems") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Map si (Timed a)))))

initialServerStore :: ServerStore si a Source #

A server store to start with

This store contains no items.

Processing a sync request

processServerSync Source #

Arguments

:: (Ord si, Monad m)
=> m si	The action that is guaranteed to generate unique identifiers
-> ServerStore si a
-> SyncRequest ci si a
-> m (SyncResponse ci si a, ServerStore si a)

Serve an SyncRequest using the current ServerStore, producing an SyncResponse and a new ServerStore.

data ServerSyncProcessor ci si a m Source #

Constructors

ServerSyncProcessor
Fields serverSyncProcessorRead :: !(m (Map si (Timed a))) Read all items serverSyncProcessorAddItem :: !(a -> m si) Add an item with `initialServerTime` serverSyncProcessorChangeItem :: !(si -> ServerTime -> a -> m ()) Update an item serverSyncProcessorDeleteItem :: !(si -> m ()) Delete an item

Instances

Generic (ServerSyncProcessor ci si a m) Source #
Instance details Defined in Data.Mergeful.Collection Associated Types type Rep (ServerSyncProcessor ci si a m) :: Type -> Type # Methods from :: ServerSyncProcessor ci si a m -> Rep (ServerSyncProcessor ci si a m) x # to :: Rep (ServerSyncProcessor ci si a m) x -> ServerSyncProcessor ci si a m #
type Rep (ServerSyncProcessor ci si a m) Source #
Instance details Defined in Data.Mergeful.Collection type Rep (ServerSyncProcessor ci si a m) = D1 (MetaData "ServerSyncProcessor" "Data.Mergeful.Collection" "mergeful-0.2.0.0-Czn7HU9ZrLaB0R8xfAleR6" False) (C1 (MetaCons "ServerSyncProcessor" PrefixI True) ((S1 (MetaSel (Just "serverSyncProcessorRead") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (m (Map si (Timed a)))) :: S1 (MetaSel (Just "serverSyncProcessorAddItem") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (a -> m si))) :: (S1 (MetaSel (Just "serverSyncProcessorChangeItem") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (si -> ServerTime -> a -> m ())) :*: S1 (MetaSel (Just "serverSyncProcessorDeleteItem") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (si -> m ())))))

processServerSyncCustom Source #

Arguments

:: (Ord si, Monad m)
=> ServerSyncProcessor ci si a m	Your server sync processor
-> SyncRequest ci si a
-> m (SyncResponse ci si a)

Process a server sync

Implementation Details

Expand

There are four cases for the items in the sync request

Added (A)
Synced (S)
Changed (C)
Deleted (D)

Each of them present options and may require action on the sever side:

Added:
- Client Added (CA) (This is the only case where a new identifier needs to be generated.)
Synced:
- Server Changed (SC) (Nothing)
- Server Deleted (SD) (Nothing)
Changed:
- Client Changed (CC) (Update value and increment server time)
- Change Conflict (CConf) (Nothing)
- Server Deleted Conflict (SDC) (Nothing)
Deleted:
- Client Deleted (CD) (Delete the item)
- Client Deleted Conflict (CDC) (Nothing)
Extra:
- Server Added (SA) (Nothing)

For more detailed comments of the nine cases, see the source of processServerItemSync in the Data.Mergeful.Item.

emptySyncResponse :: SyncResponse ci si a Source #

A sync response to start with.

It is entirely empty.

initialServerTime :: ServerTime Source #

A server time to start with.

incrementServerTime :: ServerTime -> ServerTime Source #

Increment a server time.