knex-postgis
Extension for use postgis functions in knex SQL query builder.
Example
This example show the sql generated by the extension.
const knex = require('knex');
const knexPostgis = require('knex-postgis');
const db = knex({
client: 'postgres'
});
// install postgis functions in knex.postgis;
const st = knexPostgis(db);
/* or:
* knexPostgis(db);
* const st = db.postgis;
*/
// insert a point
const sql1 = db.insert({
id: 1,
geom: st.geomFromText('Point(0 0)', 4326)
}).into('points').toString();
console.log(sql1);
// insert into "points" ("geom", "id") values (ST_geomFromText('Point(0 0)'), '1')
// find all points return point in wkt format
const sql2 = db.select('id', st.asText('geom')).from('points').toString();
console.log(sql2);
// select "id", ST_asText("geom") as "geom" from "points"
// all methods support alias
const sql3 = db.select('id', st.asText(st.centroid('geom')).as('centroid')).from('geometries').toString();
console.log(sql3);
// select "id", ST_asText(ST_centroid("geom")) as "centroid" from "geometries"Currently supported functions
- area(geom), see postgis documentation
- asText(column), see postgis documentation
- asGeoJSON(column), see postgis documentation
- asEWKT(column), see postgis documentation
- buffer(geom, radius), see postgis documentation
- centroid(geom), see postgis documentation
- distance(geom, geom), see postgis documentation
- distanceSphere(geom, geom), see postgis documentation
- dwithin(geom, geom, distance, /* optional bool spheroid */), see postgis documentation
- intersection(geom1, geom2), see postgis documentation
- intersects(geom1, geom2), see postgis documentation
- geography(geom)
- geographyFromText(ewkt), see postgis documentation
- geometry(geography)
- geomFromText(geom, srid), see postgis documentation
- geomFromGeoJSON(geojson /object, string or column name/), see postgis documentation
- makeEnvelope(minlon, minlat, maxlon, maxlat, /* optional integer SRID */), see postgis documentation
- makePoint(lon, lat, /* optional z /, / optional measure */), see postgis documentation
- makeValid(geom), see postgis documentation
- point(lon, lat), see postgis documentation
- transform(geom, srid), see postgis documentation
- within(geom, geom), see postgis documentation
- setSRID(geom, srid), see postgis documentation
- x, see postgis documentation
- y, see postgis documentation
- z, see postgis documentation
- m, see postgis documentation
- boundingBoxIntersects(geom a, geom b), represented as
a && b, see postgis documentation - boundingBoxContained(geom a, geom b), represented as
a @ b, see postgis documentation - boundingBoxContains(geom a, geom b), represented as
a ~ b, see postgis documentation - multi(geom), see postgis documentation
Define extra functions
const knex = require('knex');
const knexPostgis = require('knex-postgis');
const db = knex({
client: 'postgres'
});
knexPostgis(db);
db.postgisDefineExtras((knex, formatter) => ({
utmzone(geom) {
return knex.raw('utmzone(?)', [formatter.wrapWKT(geom)]);
}
}));
//now you can use st.utmzone function in the same way as predefined functions