Tilelive module for generating Mapbox Vector Tiles from a Postgres DB using ST_AsMVT.
Requires a postgres function that takes 3 int arguments(zoom, x, y) and returns vector tile data to exist. It is suitable for use with functions generated by the generate-sqltomvt tool from the OpenMapTiles project, or other a custom function with a similar signature.
CREATE OR REPLACE FUNCTION gettile(zoom integer, x integer, y integer)
RETURNS bytea AS $$
ST_AsMVT(t, 'admin', 4096, 'mvtgeometry'), '') as mvtl FROM (
SELECT ST_AsMVTGeom(geometry, ST_TileEnvelope(zoom, x, y), 4096, 4, true) AS mvtgeometry, id, name
FROM my_table WHERE geometry && ST_TileEnvelope(zoom, x, y);
$$ LANGUAGE SQL STABLE RETURNS NULL ON NULL INPUT;
asmvt:///?host=localhost&user=postgres&database=osm&port=15432&function=gettile
user- postgres user, defaults toPGUSERenvironment variable if not provided.host- postgres host, defaults toPGHOSTenvironment variable if not provided.database- database name, defaults toPGDATABASEenvironment variable if not provided.password- postgres password, defaults toPGPASSWORDenvironment variable if not provided.port- postgres port, defaults toPGPORTenvironment variable if not provided.function- REQUIRED - name of database function that returns tile data.