osm-read - an openstreetmap XML and PBF parser for node.js and the browser

1. Introduction
2. Usage Examples
   1. Simple Usage Example
   2. Parse OSM XML from URL Example
   3. PBF random access parser
3. Version Upgrade Guide
4. TODOs
5. License
6. Contact

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Introduction

osm-read parses openstreetmap XML and PBF files as described in http://wiki.openstreetmap.org/wiki/OSM_XML and http://wiki.openstreetmap.org/wiki/PBF_Format

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Continuous Integration

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Simple Usage Example

The following code is used to parse openstreetmap XML or PBF files in a SAX parser like callback way.

var parser = osmread.parse({
    filePath: 'path/to/osm.xml',
    endDocument: function(){
        console.log('document end');
    },
    bounds: function(bounds){
        console.log('bounds: ' + JSON.stringify(bounds));
    },
    node: function(node){
        console.log('node: ' + JSON.stringify(node));
    },
    way: function(way){
        console.log('way: ' + JSON.stringify(way));
    },
    relation: function(relation){
        console.log('relation: ' + JSON.stringify(relation));
    },
    error: function(msg){
        console.log('error: ' + msg);
    }
});

// you can pause the parser
parser.pause();

// and resume it again
parser.resume();

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Parse PBF in the browser

The browser bundle 'osm-read-pbf.js' provides a global variable 'pbfParser' with a 'parse' method.

Example, see also example/pbf.html:

<script src="../osm-read-pbf.js"></script>
<script>
    pbfParser.parse({
        filePath: 'test.pbf',
        endDocument: function(){
            console.log('document end');
        },
        node: function(node){
            console.log('node: ' + JSON.stringify(node));
        },
        way: function(way){
            console.log('way: ' + JSON.stringify(way));
        },
        relation: function(relation){
            console.log('relation: ' + JSON.stringify(relation));
        },
        error: function(msg){
            console.error('error: ' + msg);
            throw msg;
        }
    });
</script>

As an alternative to passing an URL in "filePath", the option "buffer" can be used to pass an already loaded ArrayBuffer object:

var buf = ... // e.g. xhr.response

pbfParser.parse({
    buffer: buf,
...

A third alternative is to let the user choose a local file using the HTML5 File API, passing the file object as "file" option:

<input type="file" id="file" accept=".pbf">
<script>
    document.getElementById("file").addEventListener("change", parse, false);

    function parse(evt) {
        var file = evt.target.files[0];

        pbfParser.parse({
            file: file,
        ...

See also example/file.html

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Build

Build or update the browser bundle osm-read-pbf.js with browserify:

$ npm run browserify

To install browserify (http://browserify.org/):

$ npm install -g browserify

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Parse OSM XML from URL Example

Currently you can only parse OSM data in XML from URLs. Here's an example:

osmread.parse({
    url: 'http://overpass-api.de/api/interpreter?data=node(51.93315273540566%2C7.567176818847656%2C52.000418429293326%2C7.687854766845703)%5Bhighway%3Dtraffic_signals%5D%3Bout%3B',
    format: 'xml',
    endDocument: function(){
        console.log('document end');
    },
    bounds: function(bounds){
        console.log('bounds: ' + JSON.stringify(bounds));
    },
    node: function(node){
        console.log('node: ' + JSON.stringify(node));
    },
    way: function(way){
        console.log('way: ' + JSON.stringify(way));
    },
    relation: function(relation){
        console.log('relation: ' + JSON.stringify(relation));
    },
    error: function(msg){
        console.log('error: ' + msg);
    }
});

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PBF random access parser

The following code allows to create a random access openstreetmap PBF file parser:

osmread.createPbfParser({
    filePath: 'path/to/osm.pbf',
    callback: function(err, parser){
        var headers;

        if(err){
            // TODO handle error
        }

        headers = parser.findFileBlocksByBlobType('OSMHeader');

        parser.readBlock(headers[0], function(err, block){
            console.log('header block');
            console.log(block);

            parser.close(function(err){
                if(err){
                    // TODO handle error
                }
            });
        });
    }
});

Don't forget to close the parser after usage!

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Version Upgrade Guide

Sometimes APIs change... they break your code but things get easier for the rest of us. I'm sorry if a version upgrade gives you some extra hours. To makes things a little less painfull you can find migration instructions in the file ChangeLog.

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TODOs

XML parser:

• parse timestamps

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License

See file COPYING for details.

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Contact

author: Markus Peröbner markus.peroebner@gmail.com