Ilya Rosenfeld | OpenGeo | Spring 2013

GeoScript

A library for processing of spatial data

Several implementations for scripting environments

Currently in Python, Groovy, JavaScript, Scala, Ruby

GeoTools under the hood

The Big Idea

Easy to learn

Simple to use

Familiar spatial metaphors

Choice of a scripting language

Versatile products

Evolving, free and open source

Why GeoScript

"Succinctness is Power."

- Paul Graham Author or "Hackers and Painters"

GeometryFeature

WorkspaceFilterLayer

Spatial Metaphors and API

StyleMap

ProjectionFunctionProcess

http://www. geoscript.org

# import librariesfrom geoscript.layer import Shapefile from geoscript.render import drawfrom geoscript.style import *

# load datasolar = Shapefile("solar_dni_polygons_fla.shp")

# style and display itsolar.style = Stroke("blue")draw(solar)

Load, style and display data ...

... output

# show structure of the datasolar.schema

# print out a single attribute for each recordfor f in states.features(): print f["STATE"]

# aggregate all values of "DEC" attribute list = [f.get("DEC") for f in solar.features()]reduce(lambda a,b: a+b, list)

Examine data ...

... output

shapefile's schema:solar_dni_polygons_fla [the_geom: MultiPolygon, ID: long, GRIDCODE: float, ANN_DNI: float, JAN: float, FEB: float, MAR: float, APR: float, MAY: float, JUN: float, JUL: float, AUG: float, SEP: float, OCT: float, NOV: float, DEC: float]

"DEC" attribute values:[4.268077957, 4.268077957, 4.268077957, 4.268077957...

aggregate value of "DEC":6791.922061828683

# importfrom geoscript.plot import bar

# populate data for X axisx = [1,2,3,4,5,6,7,8,9,10]

# populate data for Y axisy = [i * i for i in x]

# draw histogrambar.xy(zip(x,y)).show()

Build a Histogram ...

... output

GeoScript ProcessesAddCoverages, AreaGrid, Contour, CropCoverage, MultiplyCoverages, PolygonExtraction, RangeLookup, RasterAsPointCollection, RasterZonalStatistics, ScaleCoverage, StyleCoverage, length, isEmpty, contains, disjoint, intersects, isClosed, isValid, buffer, getY, getX, union, intersection, difference, distance, envelope, dimension, overlaps, reproject, simplify, isSimple, equalsExact, getGeometryN, isWithinDistance, touches, crosses, within, relate, convexHull, symDifference, centroid, interiorPoint, numPoints, area, isRing, exteriorRing, numInteriorRing, numGeometries, geometryType, boundary, relatePattern, equalsExactTolerance, pointN, startPoint, endPoint, interiorRingN, densify, polygonize, splitPolygon, Aggregate, BarnesSurface, Bounds, BufferFeatureCollection, Centroid, Clip, CollectGeometries, Count, Feature, Grid, Heatmap, InclusionFeatureCollection, IntersectionFeatureCollection, LRSGeocode, LRSMeasure, LRSSegment, Nearest, PointBuffers, PointStacker, Query, RectangularClip, Reproject, Simplify, Snap, Transform, UnionFeatureCollection, Unique, VectorToRaster, VectorZonalStatistics, ...

+ WRITE YOUR OWN

# importfrom geoscript.process import Process

# bind to a process and examine its inputsp = Process.lookup("vec:Centroid")p.inputs

# execute process centroids = p.run(features=solar).get("result")

# draw result draw(centroids)

Run a process ...

... output

>> Establishing Internet Connection ...

In a nutshell:

● WPS: Web Processing Service● web service interface standard● standardizes metadata, inputs and outputs of a (spatial) process● defines how a client can execute the process● implementation: some processing algorithm

OGC WPS [HTTP] Operations:

● GetCapabilities: returns service metadata● DescribeProcess: returns description of a process, its inputs and outputs● Execute: returns output of a process

OGC WPS input output

Step 1: Hack GeoScript from command line. Step 2: Wrap your code in a Process.Step 3: Copy to GeoServer.

It lives, it runs!

WPS How-to

WPS Example

origin

http://suite.opengeo.org/docs/processing/scripting/processcreate.html

inputs● GML● WKT● HTTP reference● subprocess● feature collection

○ WFS collection○ JSON○ Shapefile ZIP○ HTTP request○ GeoServer VECTOR_LAYER○ subprocess

Process Inputs and Outputs

outputs● WKT● GML● Shapefile ZIP● ...

inputs● TIFF● ArcGrid● HTTP reference● GeoServer RASTER_LAYER● subprocess

outputs● TIFF● ArcGrid● ...

vector

raster

Pushing AheadGeoScript ● do processing from command line● prototype and tweak your process● use local and remote resources

Process Chaining● script complex processes● wrap and deploy as a single service

Rendering Transformations● add advanced visualizations● author transformations using SLD● transform datasets in GeoServer

Pushing AheadIntegration● invoke WPS from another system● embed interactive maps into other apps

Web Mapping App Development● use OpenGeo Suite SDK● create a starter app automatically● customize, test and deploy

blog.opengeo.orgkeyword: "solar"