| result.* | |
| node_modules/ |
We are gonna use a Postgis datasource to check variables propagation. To run the scripts we expect:
postgresql://postgres@localhost:5432/postgres, with PostGIS.npm install
It's possible to use variables with mapnik.Image, check with:
node test-image.js
However, it's not possible to use them with mapnik.Grid, check with:
node test-grid.js
| { | |
| "private": true, | |
| "name": "node-mapnik-grid-variables", | |
| "version": "1.0.0", | |
| "description": "", | |
| "main": "test-grid.js", | |
| "dependencies": { | |
| "mapnik": "^3.6.0" | |
| } | |
| } |
| <?xml version="1.0" encoding="utf-8"?> | |
| <!DOCTYPE Map[]> | |
| <Map srs="+init=epsg:3857" maximum-extent="-20037508.3,-20037508.3,20037508.3,20037508.3"> | |
| <Parameters> | |
| <Parameter name="maximum-extent"><![CDATA[-20037508.3,-20037508.3,20037508.3,20037508.3]]></Parameter> | |
| <Parameter name="format">png8:m=h</Parameter> | |
| <Parameter name="interactivity_layer">basic</Parameter> | |
| <Parameter name="interactivity_fields">id,size</Parameter> | |
| </Parameters> | |
| <Style name="basic" filter-mode="first"> | |
| <Rule> | |
| <MarkersSymbolizer width="10 * [size]" fill="#ff0000" fill-opacity="0.9" allow-overlap="true" stroke-width="0" stroke="#ffffff" stroke-opacity="1" comp-op="multiply" clip="true" /> | |
| </Rule> | |
| </Style> | |
| <Layer name="basic" | |
| srs="+init=epsg:3857"> | |
| <StyleName>basic</StyleName> | |
| <Datasource> | |
| <Parameter name="type"><![CDATA[postgis]]></Parameter> | |
| <Parameter name="host"><![CDATA[localhost]]></Parameter> | |
| <Parameter name="port"><![CDATA[5432]]></Parameter> | |
| <Parameter name="user"><![CDATA[postgres]]></Parameter> | |
| <Parameter name="password"></Parameter> | |
| <Parameter name="dbname"><![CDATA[postgres]]></Parameter> | |
| <Parameter name="geometry_field"><![CDATA[the_geom_webmercator]]></Parameter> | |
| <Parameter name="srid"><![CDATA[3857]]></Parameter> | |
| <Parameter name="table"><![CDATA[(SELECT i AS id, ST_SetSRID(ST_MakePoint(i*1000000,0), 3857) AS the_geom_webmercator, @size AS size FROM generate_series(1,5) as i) as _query]]></Parameter> | |
| <Parameter name="extent"><![CDATA[-20037508.3,-20037508.3,20037508.3,20037508.3]]></Parameter> | |
| <Parameter name="simplify_geometries"><![CDATA[false]]></Parameter> | |
| <Parameter name="row_limit"><![CDATA[0]]></Parameter> | |
| <Parameter name="persist_connection"><![CDATA[false]]></Parameter> | |
| <Parameter name="twkb_encoding"><![CDATA[true]]></Parameter> | |
| </Datasource> | |
| </Layer> | |
| </Map> |
| 'use strict'; | |
| var mapnik = require('mapnik'); | |
| var fs = require('fs'); | |
| var assert = require('assert'); | |
| mapnik.register_default_fonts(); | |
| mapnik.register_default_input_plugins(); | |
| var map = new mapnik.Map(256, 256); | |
| var size = 10; | |
| map.load('./postgis-variables.xml', function(err, map) { | |
| assert.ifError(err); | |
| map.zoomAll(); | |
| var grid = new mapnik.Grid(256, 256); | |
| map.render(grid, { layer: 0, fields: ['id', 'size'], variables: { size: size } }, function(err, grid) { | |
| assert.ifError(err); | |
| grid.encode({format: 'utf'}, function(err, result) { | |
| assert.ifError(err); | |
| var keys = Object.keys(result.data).filter(function(k) { return k !== ''; }); | |
| assert.equal(keys.length, 5); | |
| keys.forEach(function(k) { | |
| assert.equal(result.data[k].size, size); | |
| }); | |
| fs.writeFile('result.grid.json', JSON.stringify(result, null, 4), 'utf-8'); | |
| }); | |
| }); | |
| }); |
| 'use strict'; | |
| var mapnik = require('mapnik'); | |
| var fs = require('fs'); | |
| var assert = require('assert'); | |
| mapnik.register_default_fonts(); | |
| mapnik.register_default_input_plugins(); | |
| var map = new mapnik.Map(256, 256); | |
| var size = 10; | |
| map.load('./postgis-variables.xml', function(err, map) { | |
| assert.ifError(err); | |
| map.zoomAll(); | |
| var image = new mapnik.Image(256, 256); | |
| map.render(image, {variables: { size: size }}, function(err, im) { | |
| assert.ifError(err); | |
| im.encode('png', function(err, buffer) { | |
| assert.ifError(err); | |
| fs.writeFile('result.png', buffer); | |
| }); | |
| }); | |
| }); |