Scripting GeoServer Jared Erickson

CUGOSDecember 2012

GEOSERVER

Open Source (GPL) WMS Server

Main language is Java

Also implements WFS, WCS, WPS, ect...

Uses GeoTools and JTS libraries

Scripting ModuleGeoserver Community Module

Developed by: Justin Deoliveira and Tim Schaub

I am adding Geoscript Groovy supporthttps://github.com/jericks/geoserver/tree/script_groovy

Python, JavaScript, Groovy, BeanShell, Ruby

Uses javax.scripting to execute scripts

Extend GeoServer on the fly

Scripting Hooks

Applications

Web Processing Services (WPS)

Geospatial web services

Rendering Transformations in SLD

Filter Functions

String, Date, Geometry Functions in SLD

Script Location

$DATA_DIR/scripts/appsfunctionwpslib

Scripts dynamically reloaded

Python, JavaScript, and Groovy have GeoScript API

Applications

Generic web applications or web services

Python - WSGI

JavaScript - JSGI

Groovy - Restlet

Hello World App

1 import org.restlet.data.*2 3 def run(request, response) {4 response.setEntity("Groovy rocks!", MediaType.TEXT_PLAIN)5 }

$DATA_DIR/scripts/apps/hello/main.groovy

Color Brewer App

1 import org.restlet.data.* 2 import org.restlet.resource.OutputRepresentation 3 import javax.imageio.ImageIO 4 import geoscript.filter.Color 5 import groovy.xml.MarkupBuilder 6 7 def run(request, response) { 8 String name = request.getResourceRef().getQueryAsForm().getFirstValue("name") 9 if (name) {10 def image = Color.drawToImage(Color.getPaletteColors(name))11 def output = new OutputRepresentation(MediaType.IMAGE_PNG) {12 void write(OutputStream out) throws IOException {13 ImageIO.write(image,"png",out)14 }15 }16 response.setEntity(output)17 }18 else {19 def out = new StringWriter()20 def html = new MarkupBuilder(out)21 html.html {22 head {23 title: "Color Brewer Palettes"24 }25 body {26 h1 "Color Brewer Palettes"27 ul {28 Color.paletteNames.each { nm ->29 li {30 a href: "colorbrewer?name=${nm}", "${nm}"31 }32 }33 }34 }35 }36 response.setEntity(out.toString(), MediaType.TEXT_HTML)37 }38 }

$DATA_DIR/scripts/apps/colorbrewer/main.groovy

Color Brewer App

Function List app

1 import org.restlet.data.* 2 import geoscript.filter.Function 3 import groovy.xml.MarkupBuilder 4 5 def run(request, response) { 6 def out = new StringWriter() 7 def html = new MarkupBuilder(out) 8 html.html { 9 head {10 titie: "Filter Functions"11 }12 body {13 h1 "Filter Function"14 ul {15 Function.functionNames.each { nm ->16 li "${nm}"17 }18 }19 }20 }21 response.setEntity(out.toString(), MediaType.TEXT_HTML)22 23 }

$DATA_DIR/scripts/apps/functions/main.groovy

Function List app

Groovy Geoserver APIgeoserver

Geoserver: Main entry point for Catalog and Config

Config: Metadata about GeoServer

geoserver.catalog

Catalog: Contains Workspaces, Layers, Stores

Workspace: Contains Stores

Store: Contains Layers, Converts to GeoScript Workspace

Layer: Converts to GeoScript Layer

layer as table app

1 import org.restlet.data.* 2 import geoserver.* 3 import groovy.xml.MarkupBuilder 4 5 def run(request, response) { 6 7 def layer = new GeoServer().catalog.getLayer("sf:archsites") 8 def gsLayer = layer.geoScriptLayer 9 10 def out = new StringWriter()11 def html = new MarkupBuilder(out)12 html.html {13 head {14 title: "Layer Table"15 }16 body {17 h1 "${layer.name}"18 table(border:1) {19 tr {20 gsLayer.schema.fields.each {fld ->21 td "${fld.name}"22 }23 }24 gsLayer.eachFeature { f ->25 tr {26 f.attributes.each { att ->27 td "${att.value}"28 }29 }30 }31 }32 }33 }34 response.setEntity(out.toString(), MediaType.TEXT_HTML)35 }

$DATA_DIR/scripts/apps/table/main.groovy

Layer as table app

Filter FunctionsTransform a value before displaying it

Format a date or a number

Capitalize a string

Manipulate a geometry

GeoTools input objects are wrapped as GeoScript objects

GeoScript result objects are unwrapped as GeoTools objects

Filter Function

1 /** 2 * Convert a Geometry into a buffered centroid 3 * @param value The Feature 4 * @param args A List of arguments 5 * args[0] is the Geometry 6 * args[1] is the buffer distance 7 */ 8 def run(value, args) { 9 args[0].centroid.buffer(args[1] as double)10 }

$DATA_DIR/scripts/function/bufferCentroid.groovy

Geometry filter function 1 <?xml version="1.0" encoding="ISO-8859-1"?> 2 <StyledLayerDescriptor version="1.0.0" 3 xsi:schemaLocation="http://www.opengis.net/sld StyledLayerDescriptor.xsd" 4 xmlns="http://www.opengis.net/sld" xmlns:ogc="http://www.opengis.net/ogc" 5 xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> 6 <NamedLayer> 7 <Name>Buffered Centroid</Name> 8 <UserStyle> 9 <Title>Buffered Centroids Polygons</Title>10 <Abstract>Draw buffered centroids of polygons</Abstract>11 <FeatureTypeStyle>12 <Rule>13 <Name>Rule 1</Name>14 <Title>Gray Polygon with Black Outline</Title>15 <Abstract>A polygon with a gray fill and a 1 pixel black outline</Abstract>16 <PolygonSymbolizer>17 <Geometry>18 <ogc:Function name="bufferCentroid">19 <ogc:PropertyName>the_geom</ogc:PropertyName>20 <ogc:Literal>1</ogc:Literal>21 </ogc:Function>22 </Geometry>23 <Fill>24 <CssParameter name="fill">#AAAAAA</CssParameter>25 </Fill>26 <Stroke>27 <CssParameter name="stroke">#000000</CssParameter>28 <CssParameter name="stroke-width">1</CssParameter>29 </Stroke>30 </PolygonSymbolizer>31 </Rule>32 </FeatureTypeStyle>33 </UserStyle>34 </NamedLayer>35 </StyledLayerDescriptor>

Geometry Filter Function

WPS

Web Processing Service

Model builder for the web

Generic web services for spatial data

GeoTools inputs are wrapped as GeoScript objects

GeoScript results are unwrapped as GeoTools objects

Geometry Buffer WPS

1 import geoscript.geom.Geometry 2 3 title = 'Buffer' 4 description = 'Buffers a geometry' 5 6 inputs = [ 7 geom: [name: 'geom', title: 'The geometry to buffer', type: Geometry.class], 8 distance: [name: 'distance', title: 'The buffer distance', type: Double.class] 9 ]10 11 outputs = [12 result: [name: 'result', title: 'The buffered geometry', type: Geometry.class]13 ]14 15 def run(input) {16 [result: input.geom.buffer(input.distance as double)]17 }18

$DATA_DIR/scripts/wps/buffer.groovy

WPS REQUEST BUILDER

Buffer geometry WPS

POLYGON ((11 1, 10.807852804032304 -0.9509032201612824, 10.238795325112868 -2.826834323650898, 9.314696123025453 -4.555702330196022, 8.071067811865476 -6.071067811865475, 6.555702330196023 -7.314696123025453, 4.826834323650898 -8.238795325112868, 2.9509032201612833 -8.807852804032304, 1.0000000000000007 -9, -0.9509032201612819 -8.807852804032304, -2.826834323650897 -8.238795325112868, -4.55570233019602 -7.314696123025453, -6.071067811865475 -6.0710678118654755,

-7.314696123025453 -4.555702330196022, -8.238795325112868 -2.8268343236508944, -8.807852804032306 -0.9509032201612773, -9 1.0000000000000075, -8.807852804032303 2.950903220161292, -8.238795325112862 4.826834323650909, -7.3146961230254455 6.555702330196034, -6.071067811865463 8.071067811865486,

-4.555702330196008 9.314696123025463, -2.826834323650879 10.238795325112875, -0.9509032201612606 10.807852804032308, 1.0000000000000249 11, 2.950903220161309 10.807852804032299, 4.826834323650925 10.238795325112857, 6.555702330196048 9.314696123025435, 8.071067811865499 8.07106781186545,

9.314696123025472 6.555702330195993, 10.238795325112882 4.826834323650862, 10.807852804032311 2.9509032201612437, 11 1))

http://localhost:8080/geoserver/wps?service=WPS&version=1.0.0&request=Execute&identifier=groovy:buffer&datainputs=geom=POINT%20(1%201)@mimetype=application/wkt;distance=10&RawDataOutput=result=@mimetype=application/wkt

Voronoi Layer WPS

1 import geoscript.geom.* 2 import geoscript.layer.* 3 4 title = 'VoronoiLayer' 5 description = 'Create a voronoi diagram around the features of a Layer' 6 7 inputs = [ 8 layer: [name: 'layer', title: 'The Layer', type: Layer.class], 9 ]10 11 outputs = [12 result: [name: 'result', title: 'The voronoi diagram as a Layer', type: Layer.class]13 ]14 15 def run(input) {16 def geoms = new GeometryCollection(input.layer.features*.geom.centroid)17 def output = new Layer()18 output.add([geoms.voronoiDiagram])19 [result: output]20 }21

$DATA_DIR/scripts/wps/voronoi.groovy

WPS Request Builder

Rendering transformations

Modify an entire dataset

Buffer the entire layer not each feature

Create a heatmap from points (vector to raster)

http://docs.geoserver.org/latest/en/user/styling/sld-extensions/rendering-transform.html

Rendering Transform sld

1 <?xml version="1.0" encoding="ISO-8859-1"?> 2 <StyledLayerDescriptor version="1.0.0" 3 xsi:schemaLocation="http://www.opengis.net/sld StyledLayerDescriptor.xsd" 4 xmlns="http://www.opengis.net/sld" 5 xmlns:ogc="http://www.opengis.net/ogc" 6 xmlns:xlink="http://www.w3.org/1999/xlink" 7 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> 8 <!-- a Named Layer is the basic building block of an SLD document --> 9 <NamedLayer>10 <Name>default_polygon</Name>11 <UserStyle>12 <!-- Styles can have names, titles and abstracts -->13 <Title>Default Polygon</Title>14 <Abstract>A sample style that draws a polygon</Abstract>15 <!-- FeatureTypeStyles describe how to render different features -->16 <!-- A FeatureTypeStyle for rendering polygons -->17 <FeatureTypeStyle>18 <Transformation>19 <ogc:Function name="groovy:voronoi">20 <ogc:Function name="parameter">21 <ogc:Literal>layer</ogc:Literal>22 </ogc:Function>23 </ogc:Function>24 </Transformation>25 <Rule>26 <Name>rule1</Name>27 <Title>Gray Polygon with Black Outline</Title>28 <Abstract>A polygon with a gray fill and a 1 pixel black outline</Abstract>29 <PolygonSymbolizer>30 <Fill>31 <CssParameter name="fill">#AAAAAA</CssParameter>32 </Fill>33 <Stroke>34 <CssParameter name="stroke">#000000</CssParameter>35 <CssParameter name="stroke-width">1</CssParameter>36 </Stroke>37 </PolygonSymbolizer>38 </Rule>39 </FeatureTypeStyle>40 </UserStyle>41 </NamedLayer>42 </StyledLayerDescriptor>43

Voronoi Diagram

Conclusion

GeoServer is well known as a WMS, WFS, WCS, WPS server

GeoServer is also a platform for spatial web services

Scripting just finally makes it easy

Thank you!