Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting Technical information OGC WMS – WFS – CSW

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting OGC: Open Geospatial Consortium « non-profit, international, voluntary consensus standards organization that is leading the development of standards for geospatial and location based services »  WMS: Web Map Service  WFS: Web Feature Service  Catalogue Service [CSW]

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS / WFS / CSW … Are Web Services…  Are requested « over HTTP » (use of a URL Or a HTTP form)  The parameters in the request HTTP communicate with the Web Service to indicate:  Which operation is called  With wich parameter +> Very simple to use.  They response:  A XML file (description of the response)  Or an image (Web Map Service, operation getMap)

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: Web Map Service « Provides a simple HTTP interface for requesting geo-registered map images from one or more distributed geospatial databases. » « A WMS request defines the geographic layer(s) and area of interest to be processed. » « The response to the request is one or more geo-registered map images (returned as JPEG, PNG, etc) that can be displayed in a browser application. » « The interface also supports the ability to specify whether the returned images should be transparent so that layers from multiple servers can be combined or not. »

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: getCapabilities  The first operation supported by a WMS is: getCapabilities.  Response is a XML file describing: +> The information about the server (title, abstract, access constraints,…) +> The coordinate system, area, scale, … +> The datasets (layers), with for each: * is queryable * the legend to use * the title, * … WMS: GetCapabilities:

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: getMap  The second operation supported by a WMS is: getMap  The query contains: +> The name of the layer(s) called +> The area (bbox), and the coordinate system used +> The type of the image (png, gif, …) +> The size of the image VICE=WMS&LAYERS=ITA_APATSGI_EN_500k_Lithology&SRS=EPSG:4326&BBOX= , , , &WIDTH=1143&HEIGHT =703&FORMAT=image/png&STYLES=Default&TRANSPARENT=TRUE The response is… the image

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: getMap with SLD  A SLD is a Style (Styled Layer Description) describing +> How to draw the Features WMS&request=GetMap&LAYERS=brgm:fra_nordpdc_bss_brgm&WIDTH =800&HEIGHT=500&VERSION=1.0.0&FORMAT=image/png&SRS=EPS G:27582&BBOX= , , , &STYLES=bs s WMS&request=GetMap&LAYERS=brgm:fra_nordpdc_bss_brgm&WIDTH =800&HEIGHT=500&VERSION=1.0.0&FORMAT=image/png&SRS=EPS G:27582&BBOX= , , , &STYLES=bs s_withdepth_greaterThan_200

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: getMap with SLD bss prof_debut 0 geom_l2e triangle #fffc00 #

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: getMap with SLD bss prof_fin 200 geom_l2e triangle # #

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WMS: getFeatureInfo  The third (optional) operation supported by a WMS is: getFeatureInfo  The query contains: +> The name of the layer(s) called +> The area (bbox), and the coordinate system used +> The size of the image +> The point in the image nfo&SERVICE=WMS&LAYERS=ITA_APATSGI_EN_500k_Lithology&SRS=EPSG:4326&BBOX= , , , &WIDTH=1143&HEIGHT=703&INFO_FORMAT =text/html&FORMAT=image/png&FEATURE_COUNT=100&QUERY_LAYERS=ITA_APATSGI_EN_5 00k_Lithology&STYLES=default&X=442&Y=190 The response is… the attributes

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WFS: Web Feature Service « Defines an interface specifying requests for retrieving geographic features across the Web using platform-independent calls. » « Defines interfaces and operations for data access and manipulation on a set of geographic features, including:  Get or Query features based on spatial and non-spatial constraints  Create a new feature instance  Get a description of the properties of features  Delete a feature instance  Update a feature instance  Lock a feature instance « The specified feature encoding for input and output is the Geography Markup Language (GML) although other encodings may be used. »

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting WFS: getFeature  WFS are several operations. The main is « getFeature »  The query contains: +> The name of the layer(s) called +> The filter to select features: * Area (bbox) * or other operations &maxFeatures=3&typeName=fra_nordpdc_50k_fgeol The response is an XML file displaying the features (GML)

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting Catalogue Service « Supports the ability to publish and search collections of descriptive information (metadata) about geospatial data, services and related resources. » « Providers of resources use catalogues to register metadata that conform to the provider's choice of an information model; such models include descriptions of spatial references and thematic information. » [WP4] « Client applications can then search for geospatial data and services in very efficient ways.» [WP6]

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting CSW getRecords CSW is the language used to request the catalogue service.  GetRecords: An operation to request for a list of results, according to a constraint (filter) version=2.0.2&CONSTRAINTLANGUAGE=FILTER&resultType=results&max Records=3&constraint_language_version=1.1.0&Constraint= type dataset Response in XML form. +> Used for the search engine

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting CSW getRecordById CSW is the language used to request the catalogue service.  GetRecordById: An operation to request for a record in the metadata catalogue, according to its ID W&version=2.0.2&id=2865feee55bcc2f2c d09faaa38e20c4 Response in XML form.

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting Conclusion  Simple to use  Several softwares (open source or commercial) implementing these standards  But…  Multilingual issues?  Harmonization issues? (GeoSciML for WFS, format of the getFeatureInfo response)  WFS: performance issues?

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting OneGeology Europe Services

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting Geological Survey C we b Portal Geological Survey B Geological Survey A Harmonized Web Services Harmonization:  Mapping rules (between national data model and 1G data specification)  which database, which attribute, to fill 1GE data spec  Translations (dictionaries)  for a given attribute for which a dictionary is defined, for each national database value, which common dictionary concept has to be used. Datasets WMS WFS W*S Mapping rules 1GE

Europe’s Information Society eContentplus OrléansWP6 1st Coordination and progress meeting Data Base Datasets Dictionnaries Transformation Service (coordinates) Geological Survey getCapabilities getFeatureInfo getCapabilities GeoSciML getFeatures INSPIRE WMS INSPIRE WFS 1GE D A T A M O D E L getMap 1GE SLDs ? 1GE ?