osmtogeojson

Converts OSM data to GeoJSON. Try the demo!

• stable
• real OSM polygon detection
• proper OSM multipolygon support
• full support for extended Overpass API geometry modes
• well tested and proven
• fast

This code is used in and maintained by the overpass turbo project.

Usage

command line tool

Installation:

  $ npm install -g osmtogeojson

Usage:

$ osmtogeojson file.osm > file.geojson

Supported command line options are shown with:

$ osmtogeojson --help

When working with extra large data files (≳ 100 MB) it is recommended to run the programm with a little extra memory to avoid process out of memory errors. The easiest way to do this is by running the command as

node 

--max_old_space_size=…

$ node --max_old_space_size=8192 `which osmtogeojson` large.osm > large.geojson

nodejs library

Installation:

$ npm install osmtogeojson

Usage:

var osmtogeojson = require('osmtogeojson');
osmtogeojson(osm_data);

browser library

osmtogeojson(osm_data);

API

osmtogeojson( data, options )

Converts OSM data into GeoJSON.

• data

  : the OSM data. Either as a XML DOM or in OSM JSON.

• options

  : optional. The following options can be used:

  • flatProperties

    : If true, the resulting GeoJSON feature's properties will be a simple key-value list instead of a structured json object (with separate tags and metadata). default: false

  • uninterestingTags

    : Either a blacklist of tag keys or a callback function. Will be used to decide if a feature is interesting enough for its own GeoJSON feature.

  • polygonFeatures

    : Either a json object or callback function that is used to determine if a closed way should be treated as a Polygon or LineString. read more

The result is a javascript object of GeoJSON data:

GeoJSON

The GeoJSON produced by this library will include exactly one GeoJSON-feature for each of the following OSM objects (that is everything that is also visible in overpass turbo's map view):

• all unconnected or interesting tagged nodes (POIs)
• all ways (except uninteresting multipolygon outlines)
• all multipolygons (simple multipolygons with exactly one closed outer way are present via their outer way)

All data is given as a FeatureCollection. Each Feature in the collection has an

id

node/123

properties

• type

  : the OSM data type

• id

  : the OSM id

• tags

  : a collection of all tags

• meta

  : metainformaton about the feature (e.g. version, timestamp, user, etc.)

• relations

  : an array of relations the feature is member of. Each relation is encoded as an object literal containing the following properties:

  role

  (membership role),

  rel

  (the relation's id) and

  reltags

  (contains all tags of the relation)

• tainted

  : this flag is set when the feature's geometry is incomplete (e.g. missing nodes of a way or missing ways of a multipolygon)

If the option

flatProperties

properties