Martin

Martin is a PostGIS vector tiles server suitable for large databases. Martin is written in Rust using Actix web framework.

Installation

You can download martin from Github releases page.

If you are using macOS and Homebrew you can install martin using Homebrew tap.

brew tap urbica/tap
brew install martin

Usage

Martin requires a database connection string. It can be passed as a command-line argument or as a DATABASE_URL environment variable.

martin postgres://postgres@localhost/db

Table Sources

Table Source is a database table which can be used to query vector tiles. When started, martin will go through all spatial tables in the database and build a list of table sources. A table should have at least one geometry column with non-zero SRID. All other table columns will be represented as properties of a vector tile feature.

Table Sources List

Table Sources list endpoint is available at /index.json

curl localhost:3000/index.json

Table Source TileJSON

Table Source TileJSON endpoint is available at /{schema_name}.{table_name}.json.

For example, points table in public schema will be available at /public.points.json

curl localhost:3000/public.points.json

Table Source tiles

Table Source tiles endpoint is available at /{schema_name}.{table_name}/{z}/{x}/{y}.pbf

For example, points table in public schema will be available at /public.points/{z}/{x}/{y}.pbf

curl localhost:3000/public.points/0/0/0.pbf

Function Sources

Function Source is a database function which can be used to query vector tiles. When started, martin will look for the functions with a suitable signature. A function that takes z integer, x integer, y integer, and query_params json and returns bytea, can be used as a Function Source.

Argument	Type	Description
z	integer	Tile zoom parameter
x	integer	Tile x parameter
y	integer	Tile y parameter
query_params	json	Query string parameters

Hint: You may want to use TileBBox function to generate bounding-box geometry of the area covered by a tile.

Here is an example of a function that can be used as a Function Source.

CREATE OR REPLACE FUNCTION public.function_source(z integer, x integer, y integer, query_params json) RETURNS bytea AS $$
DECLARE
  bounds geometry;
  mvt bytea;
BEGIN
  SELECT INTO bounds TileBBox(z, x, y, 3857);

  SELECT INTO mvt ST_AsMVT(tile, 'public.function_source', 4096, 'geom') FROM (
    SELECT
      ST_AsMVTGeom(geom, bounds, 4096, 64, true) AS geom
    FROM public.table_source
    WHERE geom && bounds
  ) as tile WHERE geom IS NOT NULL;

  RETURN mvt;
END
$$ LANGUAGE plpgsql IMMUTABLE STRICT PARALLEL SAFE;

Function Sources List

Function Sources list endpoint is available at /rpc/index.json

curl localhost:3000/rpc/index.json

Function Source TileJSON

Function Source TileJSON endpoint is available at /rpc/{schema_name}.{function_name}.json

For example, points function in public schema will be available at /rpc/public.points.json

curl localhost:3000/rpc/public.points.json

Function Source Tiles

Function Source tiles endpoint is available at /rpc/{schema_name}.{function_name}/{z}/{x}/{y}.pbf

For example, points function in public schema will be available at /rpc/public.points/{z}/{x}/{y}.pbf

curl localhost:3000/rpc/public.points/0/0/0.pbf

Configuration File

If you don't want to expose all of your tables and functions, you can list your sources in a configuration file. To start martin with a configuration file you need to pass a file name with a --config argument.

martin --config config.yaml

You can find an example of a configuration file here.

Using Martin with Mapbox GL JS

Mapbox GL JS is a JavaScript library for interactive, customizable vector maps on the web. It takes map styles that conform to the Mapbox Style Specification, applies them to vector tiles that conform to the Mapbox Vector Tile Specification, and renders them using WebGL.

You can add a layer to the map and specify martin TileJSON endpoint as a vector source URL. You should also specify a source-layer property. For Table Sources it is {schema_name}.{table_name} by default.

map.addLayer({
  id: "public.points",
  type: "circle",
  source: {
    type: "vector",
    url: "http://localhost:3000/public.points.json"
  },
  "source-layer": "public.points"
});

Command-line Interface

You can configure martin using command-line interface

Usage:
  martin [options] [<connection>]
  martin -h | --help
  martin -v | --version

Options:
  -h --help               Show this screen.
  -v --version            Show version.
  --workers=<n>           Number of web server workers.
  --pool_size=<n>         Maximum connections pool size [default: 20].
  --keep_alive=<n>        Connection keep alive timeout [default: 75].
  --listen_addresses=<n>  The socket address to bind [default: 0.0.0.0:3000].
  --config=<path>         Path to config file.

Environment Variables

You can also configure martin using environment variables

Environment variable	Example	Description
DATABASE_URL	postgres://postgres@localhost/db	postgres database connection
DATABASE_POOL_SIZE	20	maximum connections pool size
WORKER_PROCESSES	8	number of web server workers
KEEP_ALIVE	75	connection keep alive timeout

Using with Docker

You can use official Docker image urbica/martin

docker run \
  -p 3000:3000 \
  -e DATABASE_URL=postgres://postgres@localhost/db \
  urbica/martin

Building from Source

You can clone the repository and build martin using cargo package manager.

git clone [email protected]:urbica/martin.git
cd martin
cargo build --release

The binary will be available at ./target/release/martin.

cd ./target/release/
./martin postgres://postgres@localhost/db

Development

Install project dependencies and check if all the tests are running.

cargo test
cargo run