OpenMapTiles

Download maps from openmaptiles. We setup the mapserver using Docker as given in the Docs.

POI Data

We need to setup a POI server where we can query for the neighbourhood attractions and get a response.

We will load all the POI data as GeoJSON data into MongoDb. MongoDB has built geojson queries which we will be using.

Download Data

We will download all the openstreet map data from Geofabrik

Extracting Data

We need to extract the POI data from the File downloaded. We need to use a tool called Osmosis for this.

The command to extract the data looks like so

osmosis --read-pbf europe-latest.osm.pbf \
        --tf accept-nodes \
        aerialway=station \
        aeroway=aerodrome,helipad,heliport \
        amenity=* building=school,university craft=* emergency=* \
        highway=bus_stop,rest_area,services \
        historic=* leisure=* office=* \
        public_transport=stop_position,stop_area railway=station \
        shop=* tourism=* \
        --tf reject-ways --tf reject-relations \
        --write-xml Europe.nodes.osm

We can remove some nodes if we dont want them. The downloaded files contain all data from India but there are some data we dont need. We will scrup the data using osmconvert

In MAC we can run

wget -O - http://m.m.i24.cc/osmconvert.c | cc -x c - -lz -O3 -o osmconvert Then move the file to mv osmconvert /usr/local/bin

Now we can run the following to scrub data

osmconvert India.nodes.osm — drop-ways — drop-author — drop-relations — drop-versions India.poi.osm

Converting to GeoJSON data

For converting the .osm file to GEOJSON we use a tool ogr2ogr This can be installed using brew install gdal

We are now ready with the GEOJSON data. We will upload this to mongoDB using the npm library

geojson-to-mongo

The npm script reads the GeoJSON file we created and uploads it to mongodb.

Once the Data Is Loaded into MongoDB we can query using GeoJSON queries.

Example:

  var query = {
    $and: [
      {
        geometry: {
          $near: {
            $geometry: {
              type: "Point",
              coordinates: [options.lat, options.lng]
            },
            $maxDistance: 2000,
            $minDistance: 0
          }
        }
      },
      {
        "properties.other_tags": { $regex: "historic" }
      }
    ]
  };

Extracting details of POI

The POI data extracted has a wikidata id and wikipedia link within them. We will use that to enrich the POI with Wikipedia Extracts and Images

We can query the Wikipedia Rest API