Using INSPIRE data on the web

  Presented at the Linking Geospatial Data workshop

  More details can be found in the position paper

Background: European Location Framework

Aims at providing reference geography, contribute to the usability of INSPIRE data

Most data in ELF is from mapping and cadastral agencies

Talk is largely driven by work that interactive instruments is doing in ELF

Services and data shown are work in progress and have known issues; most data access currently requires a licence

Where are we with respect to INSPIRE data?

INSPIRE Geoportal

⇒ In many cases we can only download complete datasets

Linking - the mismatch

Linking data is fundamental in INSPIRE, to geo-reference "business data" and improve data integrity and reliability

Access to features via http

ELF provides access to data in more than one platform, including ArcGIS Online

Helsinki administrative unit feature in ArcGIS Online - in HTML or JSON

Query to all Finnish administrative unit features on level 4 in ArcGIS Online - in HTML or JSON

Helsinki gazetteer entry in ELF GeoLocator WFS

⇒ Enables links to reference data from my "business data" and access it when needed, e.g. to determine its location

Persistent identifiers

Pre-condition for linking

Recognized in INSPIRE, although persistent identifiers are often optional

ELF aims at providing reference geography: persistent identifiers are foreseen for all features

On the web, persistent identifiers should be http URIs

Sample ArcGIS Online URI: https://services1.arcgis.com/YIzHghteMOSU5dIR/arcgis/rest/services/elf_ebm_fs/FeatureServer/10/7999

Sample WFS URI: https://54.247.101.37/elf/GeolocatorService?SERVICE=WFS&REQUEST=GetFeature&typename=SI_LocationInstance& VERSION=1.1.0&OUTPUTFORMAT=text/xml;%20subtype=gml/3.1.1&FILTER=%3Cogc:Filter%20xmlns:ogc=%22http://www.opengis.net/ogc%22%3E %3Cogc:PropertyIsEqualTo%3E%3Cogc:PropertyName%20xmlns:iso19112=%22http://www.isotc211.org/19112%22 %3Eiso19112:geographicIdentifier%3C/ogc:PropertyName%3E%3Cogc:Literal%3EFI.NLS.GNR.10342733%3C/ogc:Literal%3E %3C/ogc:PropertyIsEqualTo%3E%3C/ogc:Filter%3E

Open issue: In ELF features are accessible via http URIs, but these are document URIs using OGC Web Feature Service queries or GeoServices REST API URIs

How to deal with copies?

Copies of the same feature will be available via different services - and different document URIs

Open issue: which URIs should be used in links?

If ELF would manage persistent URIs for its features, it would have to support redirecting to appropriate document URIs for the requested media type, but this is significant overhead and difficult to maintain

Implicit links

In practice, links will often be implicit. Example: NUTS codes as attribute values

Statistical data from EUROSTAT

Infant mortality data with NUTS codes

How to establish the join?

How to show features in maps that get their geo-reference from referenced features?

Not addressed in INSPIRE yet

And in ArcGIS Online?

Similar in Google Maps Engine

Geo-processing is typically used to geo-reference or otherwise enrich data, e.g. using ⇒ FME (interacting with ArcGIS Online directly)

Other options: OGC Table Join Service, OGC WFS join queries, Google Fusion Tables, Esri Maps for Office, etc.

Usability

Depends on availability of tools, APIs, good documentation

And familiarity of the user/developer with the tools/APIs

⇒ ELF supports additional platforms beyond the OGC web service technologies typically used in spatial data infrastructures

Use ELF/INSPIRE data in ArcGIS Online (compile and publish an application in 2 minutes)

Open issue: Mechanisms how to keep the copies of the data synchronized

Proxy services to avoid copies

WFS with transport network data from the city of Hamburg, accessed directly via an XtraProxy proxy service

  Clemens Portele, interactive instruments GmbH