IR on metadata Change proposal(s) on the Resource Locator element

Transcription

1 INSPIRE Infrastructure for Spatial Information in Europe IR on metadata Change proposal(s) on the Resource Locator element Type Creator Document for information and discussion CZ, DE, DK, FR, NL, ENV Date/status/version 11/06/2018 / version 1.1 Addressee Identifier Description actions: MIG MIG/8/2018/DOC14 As an outcome of the discussion on Spatial data on the web - Datasets vs distributions it was agreed to further provide clarification of how data sets and services are being linked in current ISO MD and how links are created in the INSPIRE geoportal / Thematic Viewer. From a pragmatic data provider and end use perspective, this proposal envisages to amend the use of the existing resource locator metadata element in the Metadata IR to clearly document the access to the resource through the primary/authentic view and download services. MIG to: Take note of the document and the proposal; Discuss and agree on concrete follow-up actions;

2 IR on metadata Change proposal(s) on the Resource Locator element Summary of the issue According to the INSPIRE Directive [INSPIRE Directive], member states shall establish a view service and a download service for every spatial data set that is covered by INSPIRE. A spatial data set must be downloadable through a download service and must be viewable through a view service. Remarks on coupled resource In the Implementing Rules for metadata [Regulation 1205/2008], the coupled resource concept is introduced. The coupled resource of a spatial data service is defined as the target spatial data set of this spatial data service. Given a download service and its metadata, it is clear what spatial data set can be downloaded through it by looking at the coupled resource metadata element. Given a view service and its metadata, it is clear what spatial data set can be viewed through it by looking at the coupled resource metadata element. In other words, when metadata is filled out correctly, the relation from a download/view service to its target spatial data set is clear. The last version of the Metadata TG has improved the description of this field so the way these field are filled should be correct in future. Remarks on resource locator In the Implementing Rules for metadata [Regulation 1205/2008], also the resource locator concept is introduced. Given a spatial data set, this resource locator defines the link(s) to the resource and/or the link to additional information about the resource. The resource locator of a spatial data set is mandatory if a URL is available to obtain more information on the resource, and/or access related services. Since both a download service and a view service must be established for a spatial data set covered by INSPIRE, the URLs to these services should be documented in the resource locator metadata element. This follows also out of the requirement in TG metadata A Resource locator linking to the services(s) providing online access to the described data set or data set series shall be given, if such online access is available. But, this is not an explicit requirement in the implementing rules for metadata. When only looking at these URLs, it is not clear for a client application or a user outside the SDI community, which of the URLs points to the download service and which one points to the view service and how this service should be requested. In addition, URLs to other resources may be present too. This issue is also documented in [SDWTG], where it is stated that some of the links may point to distributions 1, but there is no way for software to determine which ones. 1 With the definition of distribution taken from the Data Catalog Vocabulary: Represents a specific available form of a dataset. Each dataset might be available in different forms; these forms might represent different

3 In other words, the relation from a spatial data set to the associated download service and to the associated view service is not clear. Users search for data Also according to [SDWTG], For most users, the services are just different ways to share the dataset. In most cases, users will search for data [ ]. Metadata and view/download services only exists to support discovering, evaluating and accessing the data. [ ] In general, however, no one outside the SDI community will search for a service but, rather, only for data. Thus, when the relation from a spatial data set to the associated download service and to the associated view is not clear, this creates a bottleneck for the accessibility of spatial data sets, which is a key success factor for the implementation of the INSPIRE Directive. Optimized use of Resource Locator This proposal tries to optimize the use of the Resource Locator metadata element to facilitate the linkage from spatial data sets to the spatial data services made available to provide access to these spatial data sets. Providing more information regarding the type of the resource is supported by the ISO CI_OnlineResource metadata element to which the INSPIRE Resource Locator metadata element is mapped, but is not required in the Technical Guidelines for metadata. The function element of the ISO CI_OnlineResource element, has the possibility to define a function of the service. Optimally seen from INSPIRE point of view, one should be able to choose between at least download, view and transformation. However, in the current ISO CI_OnLineFunctionCode codelist, only download is present of these values, so the codelist should be extended, if that is an option. Various Member States (e.g. NL, ES, SE, CZ, BE, MT, AT, CS, DK, FI, LU, HU, UK, SI) use the protocol element of the ISO CI_OnlineResource element to define resources of type OGC:WMS, OGC:WMTS (view services) or OGC:WFS, OGC:WCS, OGC:SOS (download services). This additional information gives the possibility to use the resource directly. This element, is a free text element, but most member states use a codelist to identify the type of reference, they contain many corresponding values (e.g. OGC:WMTS, OGC:WMS, OGC:WFS, WWW:DOWNLOAD-1.0-http download, WWW:DOWNLOAD-1.0-ftp--download ) Since there is no clear legal obligation to provide more information on the resource type and this is also limited documented in the metadata technical guidance there is no support for this approach in INSPIRE applications such as the Thematic Viewer. formats of the dataset or different endpoints. Examples of distributions include a downloadable CSV file, an API or an RSS feed

4 Discussion in MIG-T The MIG-T discussed the possibility to make a reference in the metadata of the data set to the view and download service. This reference should be accompanied with an element indicating the type of the reference. The main question to the MIG Given the current situation (difficulties with accessing spatial data, spatial data services not showing up in catalogues ), should in the metadata of a spatial data set the explicit reference to the access point of the view and download services be mandated including an additional metadata element indicating the type of the services. Proposed change The Resource Locator element should point to the access point of the view and to the download service of the data set. In additional metadata element(s) the type of the referenced resource should be indicated, with a value of a commonly agreed codelist (to be defined) provided by the Commission and managed in the INSPIRE registry. Possible options Preferred option (for discussion): Option 1: No IR amendment / No change in the TG Description: No changes in the IR, but clarify options (e.g. in a Good Practice document). o No or slow impact on existing implementations. Applications could establish the relation via the additional element, but could not rely on it. o Applications need to become smarter, to recognize the resource type o Slow improvement on accessibility of data Option 2A: Change only TG Description: No changes in the IR, but clearer requirement in the TG that A Resource locator linking to the services(s) providing online access to the described data set or data set series shall be given, if such online access is available should be the access point to the view and the download service o In an additional function metadata element the type of the referenced resource o No additional legal obligation but a better use of the Resource Locator element. o Existing ISO codelist CI_OnLineFunctionCode should be replaced or extended, this could destroy existing implementations o Deviate from the international standard o This addition gives the information that the resource is available through view and download service, as required.

5 Option 2B: Change only TG Description: No changes in the IR, but clearer requirement in the TG that A Resource locator linking to the services(s) providing online access to the described data set or data set series shall be given, if such online access is available should be the access point to the view and the download service o In an additional protocol metadata element the type of the referenced resource o No additional legal obligation but a better use of the Resource Locator element. o Existing codelists managed by member states should contain the values of the commonly agreed codelist. o This additional information gives the possibility to use the resource directly. o Better accessibility of the data. The link between data and view and download service can be made in a more user friendly way. Option 2C: Change only TG Description: No changes in the IR, but clearer requirement in the TG that A Resource locator linking to the services(s) providing online access to the described data set or data set series shall be given, if such online access is available should be the access point to the view and the download service o In an additional function metadata element the type of the referenced resource AND o In an additional protocol metadata element the type of the referenced resource o No additional legal obligation but a better use of the Resource Locator element. o Existing ISO codelist CI_OnLineFunctionCode should be replaced or extended, this could destroy existing implementations o Deviate from the international standard o This addition gives the information that the resource is available through view and download service, as required. o This additional information gives the possibility to use the resource directly. o Existing codelists managed by member states should contain the values of the commonly agreed codelist. o Better accessibility of the data. The link between data and view and download service can be made in a more user friendly way. Option 3: Change IR and related TG Description: Require a link to the view and download service in the resource locator element, accompanied with the resource type in a function and protocol element. o See 2C and

6 o o Better accessibility of the data. The link between data and view and download service can be made in a more user friendly way. Easier to manage, less error prone. Applications and users can rely on it. References [INSPIRE Directive] Directive 2007/2/EC of the European Parliament and of the Council of 14 March 2007 establishing an Infrastructure for Spatial Information in the European Community (INSPIRE) [Regulation 1205/2008] Commission Regulation (EC) No 1205/2008 of 3 December 2008 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards metadata [TG Metadata] TEMPORARY MIG SUBGROUP FOR ACTION MIWP-8. Technical Guidance for the implementation of INSPIRE dataset and service metadata based on ISO/TS 19139:2007 [online]. Version March INSPIRE Maintenance and Implementation Group (MIG). Available from: [SDWTG] PORTELE, Clemens. Spatial Data on the Web tools and guidance for data providers [online]. Joint Research Centre (JRC), Available from: svn.jrc.ec.europa.eu/attachments/download/2178/doc- 7_ELISE_D2.1.1_Spatial_Data_on_the_Web_tools_and_guidance_for_data_providers_v1.0.pd f