datasette-basemap

A basemap for Datasette and datasette-leaflet

Installation

Install this plugin in the same environment as Datasette.

$ datasette install datasette-basemap

Usage

This plugin will make a basemap database available containing OpenStreetMap tiles for zoom levels 0-6 in the mbtiles format. It is designed for use with the datasette-tiles tile server plugin.

Demo

You can preview this map at https://datasette-tiles-demo.datasette.io/-/tiles/basemap and browse the database directly at https://datasette-tiles-demo.datasette.io/basemap

License

The data bundled with this package is © OpenStreetMap contributors, licensed under the Open Data Commons Open Database License. See this page for more details.

Development

To set up this plugin locally, first checkout the code. Then create a new virtual environment:

cd datasette-basemap
python3 -mvenv venv
source venv/bin/activate

Or if you are using pipenv:

pipenv shell

Now install the dependencies and tests:

pip install -e '.[test]'

To run the tests:

pytest

download-tiles

Download map tiles and store them in an MBTiles database

Installation

Install this tool using pip:

$ pip install download-tiles

Usage

This tool downloads tiles from a specified TMS (Tile Map Server) server for a specified bounding box and range of zoom levels and stores those tiles in a MBTiles SQLite database. It is a command-line wrapper around the Landez Python libary.

Please use this tool responsibly. Consult the usage policies of the tile servers you are interacting with, for example the OpenStreetMap Tile Usage Policy.

Running the following will download zoom levels 0-3 of OpenStreetMap, 85 tiles total, and store them in a SQLite database called world.mbtiles:

download-tiles world.mbtiles

You can customize which tile and zoom levels are downloaded using command options:

--zoom-levels=0-3 or -z=0-3

The different zoom levels to download. Specify a single number, e.g. 15, or a range of numbers e.g. 0-4. Be careful with this setting as you can easily go over the limits requested by the underlying tile server.

--bbox=3.9,-6.3,14.5,10.2 or -b=3.9,-6.3,14.5,10.2

The bounding box to fetch. Should be specified as min-lon,min-lat,max-lon,max-lat. You can use bboxfinder.com to find these for different areas.

--city=london or --country=madagascar

These options can be used instead of --bbox. The city or country specified will be looked up using the Nominatum API and used to derive a bounding box.

--show-bbox

Use this option to output the bounding box that was retrieved for the --city or --country without downloading any tiles.

--name=Name

A name for this tile collection, used for the name field in the metadata table. If not specified a UUID will be used, or if you used --city or --country the name will be set to the full name of that place.

--attribution=""Attribution string""

Attribution string to bake into the metadata table. This will default to © OpenStreetMap contributors unless you use --tiles-url to specify an alternative tile server, in which case you should specify a custom attribution string.

You can use the --attribution=osm shortcut to specify the © OpenStreetMap contributors value without having to type it out in full.

--tiles-url=https://...

The tile server URL to use. This should include {z} and {x} and {y} specifiers, and can optionally include {s} for subdomains.

The default URL used here is for OpenStreetMap, http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png

--tiles-subdomains=a,b,c

A comma-separated list of subdomains to use for the {s} parameter.

--verbose

Use this option to turn on verbose logging.

--cache-dir=/tmp/tiles

Provide a directory to cache downloaded tiles between runs. This can be useful if you are worried you might not have used the correct options for the bounding box or zoom levels.

Development

To contribute to this tool, first checkout the code. Then create a new virtual environment:

cd download-tiles
python -mvenv venv
source venv/bin/activate

Or if you are using pipenv:

pipenv shell

Now install the dependencies and tests:

pip install -e '.[test]'

To run the tests:

pytest