NodeJS pure OSM Query Engine..

Hi all,

Out of frustration on getting a Tile Server running I’ve been making a NodeJS OSM Query engine, so later I can also create a pure NodeJS Tile Server.
It requires no DB support, so basically should work on any OS/device that NodeJS runs on, I basically created a custom Database engine…

The process first requires you to convert the binary OSM data into a NodeJS friendly file format…
I’ve currently got Indexes for Node / Way / Relation ID’s, and TAG’s… I’ve yet to do a spatial index but that shouldn’t be too bad…

The size of the converted data is only about twice that of the original PBF file, eg. for world it’s about 50 gig. This is with uid, user, version, changeset, timestamp, create_by removed, but I don’t think it’s much bigger with them kept in.

As an example of what can currently be done, eg. this just averages all the lat/lons for ways with natural=wood… A strange query I know!! :slight_smile:

function testWithCache() {
    var j = new JDataRead({filePath: path.join(fn + '.build', 'jdata')});
    return j.init().then(function () {
        //simple test, query db for all ways with tag natural=wood
        //then loop and read all the nodes for each way...
        function testJDataRead6() {
            var totNodes = 0, avlat = 0, avlon = 0;
            return j.findTagAndValue('way', 'natural', 'wood').then(function (ways) {
                return common.promise_loop(0, ways.length, function (i) {
                    var way = ways[i];
                    return j.getByIds('node', way.nodeRefs).then(function (nodes) {
                        var l, node;
                        for (l = 0; l < nodes.length; l += 1) {
                            node = nodes[l];
                            //lets do something weird with, node..
                            //sum the lat & lot's up to get an average at the end..
                            avlat +=;
                            avlon += node.lon;
                            totNodes += 1;
                        return promise.resolve();
            }).then(function () {
                console.log(totNodes, avlat / totNodes, avlon / totNodes);
        //run mutlple times to see what cache does

Using east-yorkshire-with-hull-latest.osm.pbf converted the above would result in →

[D:\webdev2\tests\OSM\index.js:581] 29194 53.85765228973043 -0.43414646313283384
[console.js:84] t1: 2848ms
[D:\webdev2\tests\OSM\index.js:581] 29194 53.85765228973043 -0.43414646313283384
[console.js:84] t1: 1062ms
[D:\webdev2\tests\OSM\index.js:581] 29194 53.85765228973043 -0.43414646313283384
[console.js:84] t1: 1035ms
[D:\webdev2\tests\OSM\index.js:581] 29194 53.85765228973043 -0.43414646313283384
[console.js:84] t1: 1030ms

IOW: the first pass were the cache is empty it’s reading all the nodes for these ways at about 10,000 nodes/per second, with cache nearly 30,000 nodes/per second. And this is only using a single core of a Q9400, (hard drive)

I’ve no idea what speed PostgreSQL reads at but for a Pure javascript(NodeJS) I think that seems pretty good, especially when you consider it’s reading ways and then doing a kind of inner join on nodeRefs.

Once a query has been done, working with the data couldn’t be easer as it’s just a standard javascript object, eg. For way ref 288294538 you would get something like →

  id: 288294538,
  tags: { 
       wood: 'deciduous', 
       natural: 'wood' 
  nodeRefs: [ 2918568430, 2918568371, 2918568374, 2918568431, 2918568430 ] 

Now the reason for my Post, I’m happy to make my work opensource, but I doubt I’d have much time to maintain it etc. So I’m wondering if there are any NodeJS users out there who would be happy to take this on as a project?. I’m hoping to have a basic Tile Server running in NodeJS first though, and to tidy up what I’ve already done!!



Hi kpj_comp

I have been on github for a while now and what I can tell you is if you do not have enough time to maintain it then just put it up in a repo, write a README and say that you do not have time to maintain it. If people find it useful they can easily fork it and just move on. One important thing is to choose a appropriate license for it like AGPLv3 or other Open Source licenses.

To your project itself: I have no idea if your NodeJS module will be of much use. Also, we have already some great query languages like OverpassQL.

Hi @ypid,

I’m happy to keep my project internal for now, I’ve posted a comment on here and there has not been any response. If anybody is ever interested in such a project hopefully google will pop this thread up.

Like I said I created this out of frustration with what’s already out there. Using osm2pgsql was taking days, and making my Hard Drives sound like they were going to POP. I’ve now managed to import the world, and it took less than a day using a single Core of a Q9400. I’ve not done much since then like, as I also have to do work that pays the bills. :slight_smile:

I’m doing this project as a nice challenge for myself anyway, having such a big dataset to play with seems like fun… Next challenge get the coastline data and generate a simple Tile Server, I have some ideas of my own here rather than generating Shape files…

I just suggested it as it would be much easier to look over the current state of the project. It might also happen that someone discovers this thread like 3 years from now and you are not around for example. I am just saying. Putting the code up somewhere is always a good thing especially when you already intend to make it open source and also already have an account on github if I saw that correctly :wink:

PS: I have also tried to import the planet some time ago. The script run for more than two weeks and did not terminate. So I killed it and moved to the next thing (not sure why I started with the whole planet … Stupid idea.).