Proposed update of Technical Guidance for INSPIRE Download services based on SOS

Transcription

1 Proposed update of Technical Guidance for INSPIRE Download services based on SOS Organised by: Simon Jirka, Alexander Kotsev, Michael Lutz Dr. Simon Jirka 52 North GmbH Workshop - The Sensor Observation Service as INSPIRE Download Service for Sharing Observation Data 15 th June 2014, INSPIRE Conference 2014 Aalborg (Denmark)

2 Current State of the TG 4 INSPIRE Download Services 4.1 How the Technical Guidance maps to the Implementing Rules 4.2 Conformance Classes for Download Services Technical Guidance 4.3 Language Requirements 4.4 Implementation Roadmap for Download Services 5 Atom Implementation of Pre-defined Dataset Download Service 6 Web Feature Service and Filter Encoding Implementation of Pre-defined d Dataset Download Service 7 Web Feature Service and Filter Encoding implementation of Direct Access Download Service 8 Quality of Service 2

3 Proposal Change Overview 4 INSPIRE Download Services 4.1 How the Technical Guidance maps to the Implementing Rules Mapping the SOS-based Technical Guidance to the Implementing Rules 4.2 Conformance Classes for Download Services Technical Guidance 4.3 Language Requirements 4.44 Implementation Roadmap for Download Services 5 Atom Implementation of Pre-defined Dataset Download Service 6 Web Feature Service and Filter Encoding Implementation of Pre-defined Dataset Download Service 7 Web Feature Service and Filter Encoding implementation of Direct Access Download Service 8 Sensor Observation Service and Filter Encoding implementation of Pre-defined Dataset Download Service 9 Sensor Observation Service and Filter Encoding implementation of Direct Access Download Service 10 Quality of Service 3

4 SOS Overview - Conformance Classes SOS Core GetCapabilities, i DescribeSensor, GetObservation Spatial Filtering Profile Spatial filters allow to use the sampling geometries to filter observations XML Encoding Encoding definitions for all interface operations Core KVP Binding Invocation of SOS operations over HTTP GET with Key-Value-Pair encoding GetCapabilities, DescribeSensor, GetObservation ISO (Filter Encoding) Query performs a search over some set of resources and returns a subset of those resources. Minimum Spatial Filter Bounding box spatial operator Minimum Temporal Filter During temporal operator 4

5 Download Services and SOS Mapping Implementing Rules to SOS Conformance Classes Get Download Service Metadata SOS Core, Spatial Filtering Profile, XML Encoding, Core KVP Binding GetCapabilities Get Spatial Data Set SOS Core, Spatial Filtering Profile, XML Encoding, Core KVP Binding, ISO 19143: Query GetObservation Describe Spatial Data Set SOS Core, Spatial Filtering Profile, XML Encoding, Core KVP Binding GetCapabilities Get Spatial Object SOS Core, Spatial Filtering Profile, XML Encoding, Core KVP Binding GetObservation Describe Spatial Object Type SOS Core, Spatial Filtering Profile, XML Encoding, Core KVP Binding GetCapabilities Search Criteria for the Get Spatial Object Operation SOS Core, Spatial Filtering Profile, XML Encoding, Core KVP Binding, ISO 19143: Minimum Spatial Filter, Minimum Temporal Filter GetObservation 5

6 Pre-defined Dataset Download Service Requirements TG Requirement 70: Implementations of an SOS pre- defined d dataset t download d service shall conform to the Conformance Class SOS Core [as defined in the OGC SOS 2.0 specification]. TG Requirement 71: The Conformance Class Spatial Filtering Profile as defined by [the SOS 2.0] specification shall be enabled to ensure that each observation served through the download service provides a sampling geometry. INSPIRE Directive requirement for reference to a specific location or geographical area TG Requirement 72: Implementations of an SOS pre- defined dataset download service shall conform to the [OGC SOS 2.0] Conformance Classes Core KVP Binding and XML Encoding. 6

7 Pre-defined Dataset Download Service Requirements TG Requirement 73: A spatial dataset shall be made available through a separate SOS offering and be retrievable through a GetObservation query. Reminder: Spatial dataset = Observation offering 7

8 Pre-defined Dataset Download Service Requirements Provision of INSPIRE Metadata elements is a requirement Extend the SOS GetCapabilities response (extended capabilities section) Two options Metadata t by reference (<inspire_common:metadataurl>) i t Metadata inline TG Requirement 74: INSPIRE Metadata for the Download Service shall EITHER be linked to via an <inspire_common:metadataurl> in an extended capabilities section, OR the extended capabilities section shall contain all the INSPIRE Metadata for the Download Service in accordance with the inspire_dls:extendedcapabilities schema. 8

9 Pre-defined Dataset Download Service Requirements Multilingualism (e.g. for descriptions, abstracts), CRS and INSPIRE namespaces: GetCapabilities (Service Metadata, Observation Offerings) Default and Supported must be defined: Language and CRS INSPIRE Namespace via <inspire_dls:spatialdatasetidentifier>/<inspire_common:namespace> TG Requirement 75: For each data set, the information about supported languages, namespaces and CRS shall be provided d in the corresponding ObservationOffering Off i section in the SOS Capabilities document. TG Requirement 77: A client may specify a specific CRS in a GetObservation request. If the requested CRS is contained in the list of supported CRS, the coordinates returned in the service response shall be in the requested CRS. If the requested CRS is not supported by the service, then a corresponding exception shall be returned. TG Requirement 78: A network service [Download Service] metadata response shall contain a list of the natural languages g supported by the service. This list shall contain one or more languages that are supported. TG Requirement 79: A client may specify a specific language in a request. If the requested language is contained in the list of supported languages, the natural language fields of the service response shall be in the requested language. If the requested language is not supported by the service, then this parameter shall be ignored. 9

10 Pre-defined Dataset Download Service Requirements Language support realization for GetCapabilities Additional parameter for Core KVP Binding TG Requirement 80: The name of this parameter shall be LANGUAGE. The parameter values are based on ISO 639-2/B alpha 3 codes as used in [the INSPIRE Metadata t Implementing Rules]. Example: i t i / i REQUEST=GetCapabilities&SERVICE=[...]&VERSION= [...]&LANGUAGE=eng 10

11 Pre-defined Dataset Download Service Recommendations Language Recommendations Although further multilingual support is not required for INSPIRE Network Services, it may be desired by a service provider to implement further multilingual support such as: Multilingual error messages Multilingual support for additional Operations including HTTP/POST- and HTTP/GET-Binding Operations: GetObservation, GetObservationById, GetFeatureOfInterest, DescribeSensor 11

12 Pre-defined Dataset Download Service Recommendations CRS Recommendations TG Recommendation 22: If the CRS parameter is absent in the request, ETRS89 should be used as a default CRS. TG Recommendation 23: If a SOS server implements the optional GetFeatureOfInterest operation, the CRS handling should be implemented as it has been specified for the GetObservation operation. 12

13 Direct Access Download Service Requirements Add-on to Pre-defined Dataset Download Service Follow all requirements of Pre-defined Dataset Download Service Allow sub-setting of resulting observations Query parameters Minimum Spatial Filter (bounding box) is covered by the GetObservation operation in conjunction with the spatial filtering profile Filtering for the relevant key attributes Observed property Feature of interest Procedure Temporal filters are covered by default through the SOS interface (Minimum Temporal Filter including during a time period and equals to a time instant ). Querying by identifier of spatial object GetObservationByID 13

14 Direct Access Download Service Requirements Spatial data theme as a query parameter When a user connects to a SOS, this user already queries one specific spatial object type (defined in one spatial data theme) In case of the SOS this query parameter might not be useful 14

15 Hybrid Download Services Implementations Combinations of SOS with WFS and/or Atom: Extend/reuse existing infrastructure and provide features via WFS instances TG Recommendation 19: Implementations of SOS servers to be used as INSPIRE Download Service should support the GetFeatureOfInterest operation as defined by the SOS standard to provide access to the geometries to which the offered measurements are associated to. TG Recommendation 20: Implementations of SOS servers to be used as INSPIRE Download Service may refer to a WFS server for providing the features to which the offered measurements are associated to. In this case the feature elements returned in a SOS response should consist of URIs through which the features can be downloaded from a WFS. TG Recommendation 26: In addition, a textual reference to the Atom service implementing part A should be included in the abstract metadata element of the SOS. TG Recommendation 27: In addition, a textual reference to the WFS service providing the features of interest should be included in the abstract metadata element of the SOS. 15

16 Thank you for your attention! Questions? Simon Jirka 16