tilelive

tilelive.js

• Tilelive is a module to help interactions between tilelive source modules.
• A tilelive source is an interface implemented by node modules that deal with reading and writing map tiles.

Implementing modules

• node-mbtiles
• node-tilejson
• tilelive-mapnik
• tilelive-vector
• tilelive-bridge

Usage

Tilelive doesn't ship with any implementing modules by default. To register a module as one tilelive recognizes:

require('[implementation]').registerProtocols(tilelive);

• tilelive.list(source, callback): Lists all tilesets in a directory. source is a folder that is used by registered implementations to search for individual tilesets. callback receives an error object (or null) and a hash hash with keys being Tilestore IDs and values being Tilestore URIs. Example:

{
    "world-light": "mbtiles:///path/to/file/world-light.mbtiles",
    "mapquest": "tilejson:///path/to/file/mapquest.tilejson"
}

• tilelive.findID(source, id, callback): Looks for a particular tileset ID in a directory. callback receives an error object (or null) and the URI of the tileset.

• tilelive.load(uri, callback): Loads the Tilestore object associated with the specified uri. callback receives an error object (or null) and the Tilestore object.

• tilelive.info(uri, callback): Loads the Tilestore object associated with the specified uri and retrieves its metadata in a TileJSON compliant format. callback receives an error object (or null), the metadata hash and the Tilestore object.

• tilelive.all(source, callback): Loads metadata in a TileJSON compliant format for all tilesets in the source directory. callback receives an error object (or null) and an array with TileJSON metadata about each tileset in that directory.

• tilelive.verify(tilejson): Validates a TileJSON object and returns error objects for invalid entries.

Read/write streams

Tilelive provides an implementation of node object streams for copying tiles from one source to another.

// Copy all tiles and metadata from source A to source B.
var get = tilelive.createReadStream(sourceA);
var put = tilelive.createWriteStream(sourceB);
get.pipe(put);
put.on('finish', function() {
    console.log('done!');
});

See tilelive-copy and the streams tests for example usage of copy streams.

Parallel read streams

Tilelive can split a read operation into an arbitrary number of jobs. Pass a job parameter to options when using tilelive.createReadStream or tilelive.deserialize:

var readable = tilelive.createReadStream(src, { type: 'scanline', job: { total: 4, num: 1 } });

This instructs tilelive to only read tiles that would fall into job 1 of 4. A complete read would mean four calls each with a different num.

bin/tilelive-copy

tilelive can be used to copy data between tilestores. For a full list of options, run tilelive-copy.

Tests

To run the tests

npm test

Changelog

5.3.0

• Allows read streams to be split into parallel jobs.