abstract-point-store

abstract-point-store

Test suite & interface to implement a geographic (2D) point storage backend.

Background

An abstract point store is a data store that allows you to store, delete, and make spatial queries over many points. A point has 2 (or more) dimensional coordinates, and a value associated with it (that is compatible with the comparable-storable-types set of types).

Install

npm install abstract-point-store

Some modules that use this

• kdb-tree-store
• grid-point-store
• (COMING SOON) geohash-point-store

If you write a new one, send a PR adding it.

API

pointStore = new PointStore(opts)

Create a new point store. opts include:

• (required) opts.types: a size-3 array of comparable-storable-types strings: X coord, Y coord, value.
• (optional) opts.store: a point-store-specific storage backend for the spatial data.

pointStore.insert(pt, value[ ,cb])

pt is a size-2 array with the coordinates of the point. value is the value to be associated with this point.

pointStore.remove(pt[, opts][, cb])

Remove all points at location pt ([x, y]).

Valid opts include:

• (optional) opts.value: Only delete points at this location with this specific value.

pointStore.query(bbox[, opts][, cb])

Query for points with bbox, a size-2 array of the shape [[minX,maxX],[minY,maxY]].

Results are given as an array of points in cb(err, results). Each element in results has a point and value property.

Test suite

Publishing a test suite as a module lets multiple modules all ensure compatibility since they use the same test suite.

To use the test suite from this module you can require('abstract-point-store/tests').

An example of this can be found in the grid-point-store test setup.

To run the tests simply pass your test module (tap or tape or any other compatible modules are supported) and your store's constructor (or a setup function) in:

var tests = require('abstract-point-store/tests')
tests(require('tape'), require('your-custom-point-store'), instance-of-needed-storage-backend)

Acknowledgements

• @mafintosh and @Feross for abstract-chunk-store, which this README is heavily borrowed from.
• @maxogden for starting the immensely useful abstract-***-store pattern.
• @substack for all of the kdb-tree-store tests that served as a base for this module.

License

ISC