GIS » Gisaf

h1. Software

Gisaf (for, eg, GIS Auroville Front-end) is a web application that is under development.

[[User manual]]

[[Server]]

[[Client]]

[[Stack]]

[[Mapbox]]

h2. Database

Gisaf uses a Postgis database.

h3. Creation

To create an appropriate database, run these commands:

<pre>

createuser avgis -P

createdb avgis -O avgis

psql avgis -c "CREATE EXTENSION postgis;"

</pre>

h3. Notes

The geometry features' metadata MUST be set with the proper SRID, which can be tricky. See below.

h3. Import files

h2. Development

See the README file

h2. Configuration

TODO: more about parameters of the conf file

h3. Map

The default view of the map can be configured in the gisaf yaml config, eg:

<pre>

map:

  openMapTilesKey: cS3lrAfYXoM4MDooT6aS

  zoom: 14

  pitch: 45

  lat: 12.0000

  lng: 79.8106

  bearing: 0

  style: OSM (vector)

  opacity: 0.3

  tilesUrl: /tiles/data/india-vector.json

</pre>

h3. Production

Gisaf reads the file @/etc/gisaf/prod.yml@ at boot.

h3. Development

Gisaf reads the @~/.gisaf/prod.yml@ file at boot.

h2. Third party

h3. TileServer

"TileServer-gl":https://github.com/klokantech/tileserver-gl is a small node application that can serve vector tiles (mbtiles) for mapbox without the need for an external provider.

The maps Gisaf base layers (the definition file being located in @gisaf-app/src/app/map/base_styles.ts@) in can be parametered such that a base layer is hosted locally (see the gisaf config file).

h4. Install tileserver-gl-light

Unfortunately, it requires a much older version of node (6.x).

<pre>

yarn global add tileserver-gl-light

</pre>

h4. Download the mbtiles

From: https://openmaptiles.com/downloads/planet/ , and store the relevant one on the server's filesystem (eg. @/usr/local/2017-07-03_asia_india.mbtiles@)

h4. Service

A systemd service configuration file, in @/etc/systemd/system/tileserver-gl-light.service@:

<pre>

[Service]

ExecStart=/usr/bin/node /usr/lib/node_modules/tileserver-gl-light/src/main.js --cors true -c /etc/tileserver/conf.json

Restart=always

User=www-data

Group=www-data

Environment=NODE_ENV=production

[Install]

WantedBy=multi-user.target

</pre>

h4. Configuration

Eg, in @/etc/tileserver/conf.json@:

<pre>

{

  "options": {

    "paths": {

      "root": "",

      "sprites": "/usr/lib/node_modules/tileserver-gl-light/node_modules/tileserver-gl-styles/styles/osm-bright"

    },

    "domains": [

      "gis.auroville.org.in"

    ],

    "styles": {}

  },

  "data": {

    "india-vector": {

      "mbtiles": "/usr/local/2017-07-03_asia_india.mbtiles"

    }

  }

}

</pre>

h4. Run the service

<pre>

systemctl enable --now tileserver-gl-light.service

</pre>

h4. nginx proxy

In order the mbtiles to be served by tileserver, add in the nginx conf (adjust eventually):

<pre>

    location /tiles/ {

        proxy_pass http://127.0.0.1:8080/;

    }

</pre>

h4. Alternative for getting mbtiles: generation from osm data

Download from an OSM mirror:

<pre>

curl -O http://download.openstreetmap.fr/extracts/asia/india/tamil_nadu.osm.pbf

curl -O http://download.openstreetmap.fr/extracts/asia/india/puducherry.osm.pbf

</pre>

TODO: generation of mbtiles:

<pre>

## Need to generate a single .osm.pdf files 

ogr2ogr -f MBTILES target.mbtiles puducherry.osm.pbf -dsco MAXZOOM=15

</pre>

h4. Alternative for serving mbtiles

TODO: try

* tegola: https://github.com/go-spatial/tegola

* mbtiles-server: https://github.com/tobinbradley/mbtiles-server