Database.Haskey.Store.InMemory

Binary in-memory storage back-end. Can be used as a storage back-end for the append-only page allocator (see Data.BTree.Alloc).

Storage

data Page t where

A decoded page, of a certain type t of kind PageType.

Constructors

EmptyPage :: Page TypeEmpty

ConcurrentMetaPage :: Root root => ConcurrentMeta root -> Page TypeConcurrentMeta

OverflowPage :: Value v => v -> Page TypeOverflow

LeafNodePage :: (Key k, Value v) => Height Z -> Node Z k v -> Page TypeLeafNode

IndexNodePage :: (Key k, Value v) => Height (S h) -> Node (S h) k v -> Page TypeIndexNode

type MemoryFile = Map PageId ByteString

A file containing a collection of pages.

type MemoryFiles fp = MVar (Map fp MemoryFile)

A collection of Files, each associated with a certain fp handle.

This is shareable amongst multiple threads.

data MemoryStoreConfig

Memory store configuration.

The default configuration can be obtained by using defMemoryStoreConfig.

A configuration with a specific page size can be obtained by using memoryStoreConfigWithPageSize.

Constructors

MemoryStoreConfig

Fields

• memoryStoreConfigPageSize :: !PageSize
• memoryStoreConfigMaxKeySize :: !Word64
• memoryStoreConfigMaxValueSize :: !Word64

Instances

Show MemoryStoreConfig

Methods

showsPrec :: Int -> MemoryStoreConfig -> ShowS

show :: MemoryStoreConfig -> String

showList :: [MemoryStoreConfig] -> ShowS

Monad m => MonadReader MemoryStoreConfig (MemoryStoreT fp m)

Methods

ask :: MemoryStoreT fp m MemoryStoreConfig

local :: (MemoryStoreConfig -> MemoryStoreConfig) -> MemoryStoreT fp m a -> MemoryStoreT fp m a

reader :: (MemoryStoreConfig -> a) -> MemoryStoreT fp m a

defMemoryStoreConfig :: MemoryStoreConfig

The default configuration.

This is an unwrapped memoryStoreConfigWithPageSize with a page size of 4096.

memoryStoreConfigWithPageSize :: PageSize -> Maybe MemoryStoreConfig

Create a configuration with a specific page size.

The maximum key and value sizes are calculated using calculateMaxKeySize and calculateMaxValueSize.

If the page size is too small, Nothing is returned.

data MemoryStoreT fp m a

Monad in which binary storage operations can take place.

Two important instances are StoreM making it a storage back-end, and ConcurrentMetaStoreM making it a storage back-end compatible with the concurrent page allocator.

Instances

Monad m => MonadReader MemoryStoreConfig (MemoryStoreT fp m)

Methods

ask :: MemoryStoreT fp m MemoryStoreConfig

local :: (MemoryStoreConfig -> MemoryStoreConfig) -> MemoryStoreT fp m a -> MemoryStoreT fp m a

reader :: (MemoryStoreConfig -> a) -> MemoryStoreT fp m a

(Applicative m, Monad m, MonadIO m, MonadThrow m, Ord fp, Show fp, Typeable * fp) => StoreM fp (MemoryStoreT fp m)

Methods

openHandle :: fp -> MemoryStoreT fp m ()

lockHandle :: fp -> MemoryStoreT fp m ()

releaseHandle :: fp -> MemoryStoreT fp m ()

flushHandle :: fp -> MemoryStoreT fp m ()

closeHandle :: fp -> MemoryStoreT fp m ()

removeHandle :: fp -> MemoryStoreT fp m ()

nodePageSize :: (Key key, Value val) => MemoryStoreT fp m (Height height -> Node height key val -> PageSize)

maxPageSize :: MemoryStoreT fp m PageSize

maxKeySize :: MemoryStoreT fp m Word64

maxValueSize :: MemoryStoreT fp m Word64

getNodePage :: (Key key, Value val) => fp -> Height height -> Proxy * key -> Proxy * val -> NodeId height key val -> MemoryStoreT fp m (Node height key val)

putNodePage :: (Key key, Value val) => fp -> Height height -> NodeId height key val -> Node height key val -> MemoryStoreT fp m ()

getOverflow :: Value val => fp -> Proxy * val -> MemoryStoreT fp m val

putOverflow :: Value val => fp -> val -> MemoryStoreT fp m ()

listOverflows :: fp -> MemoryStoreT fp m [fp]

Monad m => Monad (MemoryStoreT fp m)

Methods

(>>=) :: MemoryStoreT fp m a -> (a -> MemoryStoreT fp m b) -> MemoryStoreT fp m b

(>>) :: MemoryStoreT fp m a -> MemoryStoreT fp m b -> MemoryStoreT fp m b

return :: a -> MemoryStoreT fp m a

fail :: String -> MemoryStoreT fp m a

Functor m => Functor (MemoryStoreT fp m)

Methods

fmap :: (a -> b) -> MemoryStoreT fp m a -> MemoryStoreT fp m b

(<$) :: a -> MemoryStoreT fp m b -> MemoryStoreT fp m a

Applicative m => Applicative (MemoryStoreT fp m)

Methods

pure :: a -> MemoryStoreT fp m a

(<*>) :: MemoryStoreT fp m (a -> b) -> MemoryStoreT fp m a -> MemoryStoreT fp m b

(*>) :: MemoryStoreT fp m a -> MemoryStoreT fp m b -> MemoryStoreT fp m b

(<*) :: MemoryStoreT fp m a -> MemoryStoreT fp m b -> MemoryStoreT fp m a

MonadIO m => MonadIO (MemoryStoreT fp m)

Methods

liftIO :: IO a -> MemoryStoreT fp m a

MonadThrow m => MonadThrow (MemoryStoreT fp m)

Methods

throwM :: Exception e => e -> MemoryStoreT fp m a

MonadCatch m => MonadCatch (MemoryStoreT fp m)

Methods

catch :: Exception e => MemoryStoreT fp m a -> (e -> MemoryStoreT fp m a) -> MemoryStoreT fp m a

MonadMask m => MonadMask (MemoryStoreT fp m)

Methods

mask :: ((forall a. MemoryStoreT fp m a -> MemoryStoreT fp m a) -> MemoryStoreT fp m b) -> MemoryStoreT fp m b

uninterruptibleMask :: ((forall a. MemoryStoreT fp m a -> MemoryStoreT fp m a) -> MemoryStoreT fp m b) -> MemoryStoreT fp m b

(Applicative m, Monad m, MonadIO m, MonadCatch m) => ConcurrentMetaStoreM (MemoryStoreT FilePath m)

Methods

putConcurrentMeta :: Root root => FilePath -> ConcurrentMeta root -> MemoryStoreT FilePath m ()

readConcurrentMeta :: Root root => FilePath -> Proxy * root -> MemoryStoreT FilePath m (Maybe (ConcurrentMeta root))

runMemoryStoreT

Arguments

:: MemoryStoreT fp m a

Action to run

-> MemoryStoreConfig

Configuration

-> MemoryFiles fp

Data

-> m a

Run the storage operations in the MemoryStoreT monad, given a collection of Files.

newEmptyMemoryStore :: IO (MemoryFiles hnd)

Construct a store with an empty database with name of type hnd.

Exceptions

newtype FileNotFoundError hnd

Exception thrown when a file is accessed that doesn't exist.

Constructors

FileNotFoundError hnd

Instances

Show hnd => Show (FileNotFoundError hnd)

Methods

showsPrec :: Int -> FileNotFoundError hnd -> ShowS

show :: FileNotFoundError hnd -> String

showList :: [FileNotFoundError hnd] -> ShowS

(Typeable * hnd, Show hnd) => Exception (FileNotFoundError hnd)

Methods

toException :: FileNotFoundError hnd -> SomeException

fromException :: SomeException -> Maybe (FileNotFoundError hnd)

displayException :: FileNotFoundError hnd -> String

data PageNotFoundError hnd

Exception thrown when a page that is accessed doesn't exist.

Constructors

PageNotFoundError hnd PageId

Instances

Show hnd => Show (PageNotFoundError hnd)

Methods

showsPrec :: Int -> PageNotFoundError hnd -> ShowS

show :: PageNotFoundError hnd -> String

showList :: [PageNotFoundError hnd] -> ShowS

(Typeable * hnd, Show hnd) => Exception (PageNotFoundError hnd)

Methods

toException :: PageNotFoundError hnd -> SomeException

fromException :: SomeException -> Maybe (PageNotFoundError hnd)

displayException :: PageNotFoundError hnd -> String

data WrongNodeTypeError

Exception thrown when a node cannot be cast to the right type.

As used in getNodePage.

Constructors

WrongNodeTypeError

Instances

Show WrongNodeTypeError

Methods

showsPrec :: Int -> WrongNodeTypeError -> ShowS

show :: WrongNodeTypeError -> String

showList :: [WrongNodeTypeError] -> ShowS

Exception WrongNodeTypeError

Methods

toException :: WrongNodeTypeError -> SomeException

fromException :: SomeException -> Maybe WrongNodeTypeError

displayException :: WrongNodeTypeError -> String

data WrongOverflowValueError

Exception thrown when a value from an overflow page cannot be cast.

As used in getOverflow.

Constructors

WrongOverflowValueError

Instances

Show WrongOverflowValueError

Methods

showsPrec :: Int -> WrongOverflowValueError -> ShowS

show :: WrongOverflowValueError -> String

showList :: [WrongOverflowValueError] -> ShowS

Exception WrongOverflowValueError

Methods

toException :: WrongOverflowValueError -> SomeException

fromException :: SomeException -> Maybe WrongOverflowValueError

displayException :: WrongOverflowValueError -> String