- GeoScript is a library for processing spatial data in various scripting languages like Python, Groovy, JavaScript, etc. It uses GeoTools behind the scenes. - It provides familiar spatial concepts like geometry, features, layers, and projections. Scripts can load, style, analyze, and display spatial data with just a few lines of code. - Processes written with GeoScript can be published as OGC Web Processing Services and executed remotely through a standard interface. This allows sharing and chaining of spatial analysis workflows.

1. GeoScript
Ilya Rosenfeld | OpenGeo | Spring 2013

2. The Big Idea
A library for processing of spatial data
Several implementations for scripting environments
Currently in Python, Groovy, JavaScript, Scala, Ruby
GeoTools under the hood

3. Why GeoScript
Easy to learn
Simple to use
Familiar spatial metaphors
Choice of a scripting language
Versatile products
Evolving, free and open source

4. "Succinctness is Power."
- Paul Graham
Author or "Hackers and Painters"

5. Spatial Metaphors and API
Geometry Style
Feature Map
Workspace Projection
Filter Function
Layer Process
http://www. geoscript.org

6. Load, style and display data ...
# import libraries
from geoscript.layer import Shapefile
from geoscript.render import draw
from geoscript.style import *
# load data
solar = Shapefile("solar_dni_polygons_fla.shp")
# style and display it
solar.style = Stroke("blue")
draw(solar)

7. ... output

8. Examine data ...
# show structure of the data
solar.schema
# print out a single attribute for each record
for 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)

9. ... 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

10. Build a Histogram ...
# import
from geoscript.plot import bar
# populate data for X axis
x = [1,2,3,4,5,6,7,8,9,10]
# populate data for Y axis
y = [i * i for i in x]
# draw histogram
bar.xy(zip(x,y)).show()

11. ... output

12. GeoScript Processes
AddCoverages, 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

13. Run a process ...
# import
from geoscript.process import Process
# bind to a process and examine its inputs
p = Process.lookup("vec:Centroid")
p.inputs
# execute process
centroids = p.run(features=solar).get("result")
# draw result
draw(centroids)

14. ... output

15. >> Establishing Internet Connection ...

16. OGC WPS input output
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

17. WPS How-to
Step 1: Hack GeoScript from command line.
Step 2: Wrap your code in a Process.
Step 3: Copy to GeoServer.
It lives, it runs!

18. WPS Example
origin
http://suite.opengeo.org/docs/processing/scripting/processcreate.html

19. Process Inputs and Outputs
vector
inputs
● GML outputs
● WKT ● WKT
● HTTP reference ● GML
● subprocess ● Shapefile ZIP
● feature collection ● ...
○ WFS collection
○ JSON
○ Shapefile ZIP
○ HTTP request
○ GeoServer VECTOR_LAYER
○ subprocess
outputs
raster ● TIFF
inputs ● ArcGrid
● TIFF ● ...
● ArcGrid
● HTTP reference
● GeoServer RASTER_LAYER
● subprocess

20. Pushing Ahead
GeoScript Rendering Transformations
● do processing from command line ● add advanced visualizations
● prototype and tweak your process ● author transformations using SLD
● use local and remote resources ● transform datasets in GeoServer
Process Chaining
● script complex processes
● wrap and deploy as a single service

21. Pushing Ahead
Web Mapping App Development Integration
● use OpenGeo Suite SDK ● invoke WPS from another system
● create a starter app automatically ● embed interactive maps into other apps
● customize, test and deploy

22. blog.opengeo.org
keyword: "solar"