1. Geobeyond
May 23, 2012
Geospatial engine
for sharing
meteorological
objects
Powered by GeoServer
1 Author: Francesco Bartoli

2. 2 May 23, 2012
Agenda
 What is WOML?
 GeoServer, a geospatial engine server for
consuming data
 GML application schema extension
 PostGIS, a spatial database for WOML
 Challenges
Author: Francesco Bartoli

3. 3 May 23, 2012
WOML
 Weather Objects Modeling Language
 Semantically paradigm for meteorological entities
(Fronts, Cloud Areas, Precipitation Areas, etc)
 Standard for data exchange of high-level
meteorological phenomena among expertise-less
stakeholders
 Focused on interoperability, no expectations to
data presentation
 Started from FMI in late 2008
Author: Francesco Bartoli

4. 4 May 23, 2012
WOML Schemas
 Specificationmaintained at FMI confluence
 GML application schema
 Based on top of GML 3.2.1 (latest version)
 Inheritance as mechanism for specialisation
 4 Namespaces WOML WOML WOML
SWO Quantity Textfct
 25 Features
WOML Core
Author: Francesco Bartoli

5. 5 May 23, 2012
WOML Core
 Building block for Geometry
 Point
 Line
 Surface
Author: Francesco Bartoli

6. 6 May 23, 2012
Core Feature Types
 All derived from gml:DynamicFeatureType to
describe changes while a forecast period is
observed
 gml:history property to capture changes over the
period collected as geometrically-event objects
 PointObjectEventType, LineObjectEventType,
SurfaceObjectEventType
 All of them extend gml:AbstractTimeSliceType by
adding the geometry property is changing
 Feature Collection Type (certain area, timeframe)
 WeatherForecastType
 MeteorologicalAnalysisType
Author: Francesco Bartoli

7. 7 May 23, 2012
Core Diagram
Author: Francesco Bartoli

8. 8 May 23, 2012
WOML SWO
 Sensible Weather Object types:
 14 of single point geometry inherited from Core
AbstractPointObjectType
 9 of line geometry inherited from Core
AbstractLineObjectType
 2 of surface geometry inherited from Core
AbstractSurfaceObjectType
 Example: A Ridge semantically differs from a
ColdFront despite they share the same
properties
Author: Francesco Bartoli

9. 9 May 23, 2012
SWO Diagram
Author: Francesco Bartoli

10. 10 May 23, 2012
WOML Quantity & Textfct
 The Quantity namespace is defined for
locations and areas with relevant physical
values (Temperatures, wind speed, wind
direction, etc)
 Easier replacement of OGC Observations &
Measurement for forecast and analysis
 TheTextfct namespace describes text-based
weather forecasts for specific target areas
 Focused on lightweight exchange of data
 Forecast which needs human explanation
Author: Francesco Bartoli

11. 11 May 23, 2012
Key Concepts
 Geographical nature of meteorological data
 Geospatial standards OGC WxS
 Cross-boarder cooperation and harmonisation of
data (Regional – National – European)
 Interoperability in mind
 Consuming data from WOML WFS 2.0
Autore: Francesco Bartoli

12. 12 May 23, 2012
GeoServer
 Supports OGC WxS family implementation
 Uses GeoTools to aggregate different datastores
centrally
 Includes GML application schema extension for
supporting 3th-party like WOML
 Allows direct querying of complex meteorological
features WOML-encoded
 Enables data fusion between remote and local
sources
 is Inspire-ready because of the abilities passed-
down by its extension for Inspire services
Author: Francesco Bartoli

13. 13 28 maggio 2012
OGC WFS Protocol
 Reference implementation of WFS
http://ogsuite.geobeyond.it/geoserver/wfs?
SERVICE=wfs&
VERSION=1.1.0&
REQUEST=GetFeature&
TYPENAME=usa:states&
FEATUREID=states.39
Author: Francesco Bartoli

14. 14 May 23, 2012
Consuming WOML services

15. 15 May 23, 2012
GML app-schema extension
 Place the jar file into the WEB-INF/lib directory
 Package for each feature:
 <root_dir>
 <featureType_dir>
 featuretype.xml
 layer.xml
 datastore.xml
 <featureType_mapping_file>.xml
 Mapping for WFS
 Feature Chaining for multivalued member
property (i.e. WeatherForecast)
Author: Francesco Bartoli

16. 16 May 23, 2012
Configuration
 Declaration of secondary namespace is
essential for GML 3.2.1 by WFS 2.0
 PostGIS, Oracle, ArcSDE supported as
database options for datastore
 Typical configuration:
<as : AppSchemaDataAccess>
<namespaces >... </namespaces>
<includedTypes >... </includedTypes>
<sourceDataStores >...</sourceDataStores>
<targetTypes ... </ targetTypes>
<typeMappings >... </typeMappings>
</as : AppSchemaDataAccess>
Author: Francesco Bartoli

17. 17 May 23, 2012
Feature Chaining
 CloudArea feature collection has a certain number of
SWO features nested in the multivalued property
targetRegion
 Use of complex sourceExpression combined with three childs:
 OCQL which filters out the attribute of cloud_area belonging
to the chaining
 linkElement corresponding to the targetElement of feature
which you are linking to
 linkField specifying XPath related to the feature property
significantly involved to the chaining
 A sort of LEFT JOIN “…FROM cloud_area, linkElement WHERE
<OCQL exp>…linkField”
 Resource de-normalisation as of M-M association (sorted
by FID)
Author: Francesco Bartoli

18. 18 May 23, 2012
WOML schema mapping
 Single womlswo:CloudArea:
 is observed at several distinct locations on the
Earth’s surface
 has a multivalued
womlcore:targetRegion property of
womlcore:GeographicRegionPropert
yType
Author: Francesco Bartoli

19. 19 May 23, 2012
Design WOML database
 PostGIS as natural database for a spatially-
stack
 De-normalisation left to feature chaining
 Hybrid generalisation model for SWO features
jet_stream abstract_line occluded_front
abstract_met_symbol
abstract_pressure_cente
abstract_storm cloud_area surface_precipitation_area
r
abstract_point_object abstract_line_object abstract_surface_object
abstract_meteorological_object Author: Francesco Bartoli

20. 20 May 23, 2012
Sample request
http://localhost:8080/geoserver/wfs?request=GetFeature&typeName=womlswo:CloudArea&
bbox=47.99,56.22,52.23,62.99
Response:
<wfs:FeatureCollection….>
<wfs:member>
<womlswo:CloudArea gml:id=" cloud_area .2 ">
<gml:boundedBy>
<gml:Envelope srsDimension="2" srsName="urn:x−
ogc:def:crs:EPSG:2398 ”>
<gml:lowerCorner>45.828799 51.057128</gml:lowerCorner>
<gml:upperCorner>50.903033 62.614745</gml:upperCorner>
</gml:Envelope>
</gml:boundedBy>
<womlcore:creationTime>2009−02−01T12:44:30Z</womlcore:creationTime>
<womlcore:shortInfo xml:lang="Ita−it ">Area nuvolosa interna</womlcore:shortInfo>
<womlcore:controlSurface>….</womlcore:controlSurface>
<womlcore:targetRegion>…. </womlcore:targetRegion>
….
</womlswo:CloudArea>
</wfs:member>
</wfs:FeatureCollection>
Author: Francesco Bartoli

21. 21 May 23, 2012
Key benefit
Interoperability!
Author: Francesco Bartoli

22. 22 28 maggio 2012
Challenges
 To be scoped under the authority of Italian
Civil Protection
 Schema transformation for implementing
services under Inspire Annex III –
Atmospheric Conditions and Meteorological
Geographical Features
 WOML candidated under the OGC umbrella?
 Implementing WxS Inspire-compliant service
with GeoServer Inspire extension
Author: Francesco Bartoli

23. 23 28 maggio 2012
Contact us
 Geobeyond
 Source code on
GitHubhttps://github.com/geobeyond/GEWO
ML
 Follow us on twitter
 Contact francesco.bartoli@geobeyond.it
Author: Francesco Bartoli