Database.Mbtiles

This module provides support for reading, writing, and updating an mbtiles database. There is also functionality for reading metadata from the database.

See the associated README.md for basic usage examples.

Types

data MbtilesT m a

MbtilesT monad that will run actions on an MBTiles file.

Instances

MonadTrans MbtilesT

Methods

lift :: Monad m => m a -> MbtilesT m a

Monad m => Monad (MbtilesT m)

Methods

(>>=) :: MbtilesT m a -> (a -> MbtilesT m b) -> MbtilesT m b

(>>) :: MbtilesT m a -> MbtilesT m b -> MbtilesT m b

return :: a -> MbtilesT m a

fail :: String -> MbtilesT m a

Functor m => Functor (MbtilesT m)

Methods

fmap :: (a -> b) -> MbtilesT m a -> MbtilesT m b

(<$) :: a -> MbtilesT m b -> MbtilesT m a

Applicative m => Applicative (MbtilesT m)

Methods

pure :: a -> MbtilesT m a

(<*>) :: MbtilesT m (a -> b) -> MbtilesT m a -> MbtilesT m b

(*>) :: MbtilesT m a -> MbtilesT m b -> MbtilesT m b

(<*) :: MbtilesT m a -> MbtilesT m b -> MbtilesT m a

MonadIO m => MonadIO (MbtilesT m)

Methods

liftIO :: IO a -> MbtilesT m a

type Mbtiles a = MbtilesT IO a

Type specialization of MbtilesT to IO.

type MbtilesMeta = HashMap Text Text

MBTiles files contain metadata in one of their tables. This is a type alias for a mapping between the metadata key and the metadata value.

data MBTilesError

Data type representing various errors that could occur when opening and validating an MBTiles file.

Constructors

DoesNotExist

The MBTiles file does not exist.

InvalidSchema

The MBTiles schema is invalid according to the spec.

InvalidMetadata

The MBTiles metadata table is invalid.

InvalidTiles

The MBTiles tiles table is invaid.

Instances

Eq MBTilesError

Methods

(==) :: MBTilesError -> MBTilesError -> Bool

(/=) :: MBTilesError -> MBTilesError -> Bool

Show MBTilesError

Methods

showsPrec :: Int -> MBTilesError -> ShowS

show :: MBTilesError -> String

showList :: [MBTilesError] -> ShowS

newtype Z

Newtype wrapper around map zoom level.

Constructors

Z Int

Instances

ToField Z

Methods

toField :: Z -> SQLData

newtype X

Newtype wrapper around a tile's x-coordinate.

Constructors

X Int

Instances

ToField X

Methods

toField :: X -> SQLData

newtype Y

Newtype wrapper around a tile's y-coordinate.

Constructors

Y Int

Instances

ToField Y

Methods

toField :: Y -> SQLData

Typeclasses

class ToTile a where

Typeclass representing data types that can be turned into a lazy ByteString and stored as tile data.

Minimal complete definition

toTile

Methods

toTile :: a -> ByteString

Instances

ToTile ByteString

Methods

toTile :: ByteString -> ByteString

ToTile ByteString

Methods

toTile :: ByteString -> ByteString

class FromTile a where

Typeclass representing data types intp which raw tile data can be converted.

Minimal complete definition

fromTile

Methods

fromTile :: ByteString -> a

Instances

FromTile ByteString

Methods

fromTile :: ByteString -> ByteString

FromTile ByteString

Methods

fromTile :: ByteString -> ByteString

The MbtilesT monad transformer

runMbtilesT :: MonadIO m => FilePath -> MbtilesT m a -> m (Either MBTilesError a)

Given a path to an MBTiles file, run the MbtilesT action. This will open a connection to the MBTiles file, run the action, and then close the connection. Some validation will be performed first. Of course, we will check if the MBTiles file actually exists. If it does, we need to validate its schema according to the MBTiles spec.

runMbtiles :: FilePath -> Mbtiles a -> IO (Either MBTilesError a)

Specialized version of runMbtilesT to run in the IO monad.

Mbtiles read/write functionality

getTile :: (MonadIO m, FromTile a) => Z -> X -> Y -> MbtilesT m (Maybe a)

Given a Z, X, and Y parameters, return the corresponding tile data, if it exists.

writeTile :: (MonadIO m, ToTile a) => Z -> X -> Y -> a -> MbtilesT m ()

Write new tile data to the tile at the specified Z, X, and Y parameters. This function assumes that the tile does not already exist.

writeTiles :: (MonadIO m, ToTile a) => [(Z, X, Y, a)] -> MbtilesT m ()

Batch write new tile data to the tile at the specified Z, X, and Y parameters. This function assumes that the tiles do not already exist.

updateTile :: (MonadIO m, ToTile a) => Z -> X -> Y -> a -> MbtilesT m ()

Update existing tile data for the tile at the specified Z, X, and Y parameters. This function assumes that the tile does already exist.

updateTiles :: (MonadIO m, ToTile a) => [(Z, X, Y, a)] -> MbtilesT m ()

Batch update tile data for the tiles at the specified Z, X, and Y parameters. This function assumes that the tiles do already exist.

Mbtiles metadata functionality

getMetadata :: MonadIO m => MbtilesT m MbtilesMeta

Returns the MbtilesMeta that was found in the MBTiles file. This returns all of the currently available metadata for the MBTiles database.

getName :: MonadIO m => MbtilesT m Text

Helper function for getting the specified name of the MBTiles from metadata.

getType :: MonadIO m => MbtilesT m Text

Helper function for getting the type of the MBTiles from metadata.

getVersion :: MonadIO m => MbtilesT m Text

Helper function for getting the version of the MBTiles from metadata.

getDescription :: MonadIO m => MbtilesT m Text

Helper function for getting the description of the MBTiles from metadata.

getFormat :: MonadIO m => MbtilesT m Text

Helper function for getting the format of the MBTiles from metadata.