osm-read-bj
v0.15.0-base64.1
Published
an openstreetmap XML and PBF data parser
Downloads
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Readme
osm-read - an openstreetmap XML and PBF parser for node.js and the browser
- Introduction
- Usage Examples
- Simple Usage Example
- Parse OSM XML from URL Example
- PBF random access parser
- Version Upgrade Guide
- TODOs
- License
- Contact
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
Continuous Integration
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();
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
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
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);
}
});
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!
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.
TODOs
XML parser:
- parse timestamps
License
See file COPYING for details.
Contact
author: Markus Peröbner [email protected]