Difference between revisions of "DCLite4G"
Jump to navigation
Jump to search
Wiki-JoWalsh (talk | contribs) (very quick initial notes) |
Wiki-JoWalsh (talk | contribs) m |
||
Line 1: | Line 1: | ||
− | + | '''DCLite4G''' is an effort to | |
− | |||
− | DCLite4G is an effort to | ||
* establish a common information model with mappings to well known formats for geospatial metadata | * establish a common information model with mappings to well known formats for geospatial metadata | ||
* provide a vocabulary/recommendations for spatial extensions to Dublin Core | * provide a vocabulary/recommendations for spatial extensions to Dublin Core | ||
Line 8: | Line 6: | ||
== Getting involved == | == Getting involved == | ||
+ | === Mailing List === | ||
Feel welcome to join the discussion and development [http://lists.eogeo.org/mailman/listinfo/dclite4g mailing list]: | Feel welcome to join the discussion and development [http://lists.eogeo.org/mailman/listinfo/dclite4g mailing list]: | ||
* http://lists.eogeo.org/mailman/listinfo/dclite4g | * http://lists.eogeo.org/mailman/listinfo/dclite4g | ||
Line 19: | Line 18: | ||
= Information Model = | = Information Model = | ||
− | == Core | + | == Core Model == |
=== Dublin Core === | === Dublin Core === | ||
Line 27: | Line 26: | ||
=== FGDC === | === FGDC === | ||
− | + | == References == | |
* [http://geometa.info/rappiinfo/wiki/index.php/DClite4G Dublin Core lite for Geo] | * [http://geometa.info/rappiinfo/wiki/index.php/DClite4G Dublin Core lite for Geo] | ||
Line 33: | Line 32: | ||
* [http://udig.refractions.net/docs/api-udig/net.refractions.udig.catalog/net/refractions/udig/catalog/IGeoResourceInfo.html iGeoResourceInfo class in uDig] | * [http://udig.refractions.net/docs/api-udig/net.refractions.udig.catalog/net/refractions/udig/catalog/IGeoResourceInfo.html iGeoResourceInfo class in uDig] | ||
* [http://www.geodatacommons.umaine.edu/wpapers/CGD%20Metadata%20White%20Paper%20v2.pdf GeodataCommons Metadata Whitepaper] | * [http://www.geodatacommons.umaine.edu/wpapers/CGD%20Metadata%20White%20Paper%20v2.pdf GeodataCommons Metadata Whitepaper] | ||
+ | |||
+ | = Query Interface = | ||
+ | |||
+ | == OAI-PMH == | ||
+ | |||
+ | [http://www.openarchives.org/OAI/openarchivesprotocol.html The Harvesting Protocol (version 2.0) specification] together with [http://www.openarchives.org/OAI/2.0/guidelines.htm Implementation Guidelines] | ||
+ | |||
+ | Following are specific guidelines for a minimal OAI-PMH implementation of a so called 'data provider' using only the mandatory 'unqualified' Dublin Core (DC): | ||
+ | |||
+ | * Only '''three''' operations (verbs) are needed: Identify, ListMetadataFormats and ListRecords. | ||
+ | * Following operations are not required (initially): ListIdentifiers, ListSets, GetRecord. | ||
+ | * No incremental harvesting (resumption process for ListXxx operations with more than 1000 records) | ||
+ | * No compression as defined in the OAI-PMH spec. (compression at lower http level still possible) | ||
+ | * Date granularity may be 'day' not seconds (YYYY-MM-DD) | ||
+ | * Keeping track of deleted record may not be supported (deletedRecord=no) | ||
+ | * Mandatory DC supported as data model is sufficient for a start but with specific semantics (e.g. coverage, relation) (see also example below): | ||
+ | ** dc:description contains dct:abstract | ||
+ | ** dc:coverage contains bounding box encoding as defined in http://georss.org/simple.html#Box | ||
+ | ** dc:date means in fact dct:modified | ||
+ | ** dc:relation is filled in with dclite4g:onLineSrc. If dc:type='service' dct:hasPart can be derived from GetCapabilities. | ||
+ | |||
+ | Additional bounding box query property for ListRecords. | ||
+ | |||
+ | == Others == | ||
+ | |||
+ | |||
+ | == References == | ||
+ | |||
+ | * [http://devgeo.cciw.ca/owscat/docs/index.html OWSCat] | ||
+ | * [[Simple Catalog Interface]] - links to articles, etc | ||
= See Also = | = See Also = | ||
* http://www.geometa.info/ - German geospatial data search service using dclite4g + OAI-PMH. | * http://www.geometa.info/ - German geospatial data search service using dclite4g + OAI-PMH. |
Revision as of 11:00, 16 December 2006
DCLite4G is an effort to
- establish a common information model with mappings to well known formats for geospatial metadata
- provide a vocabulary/recommendations for spatial extensions to Dublin Core
- support simple interfaces for collecting and querying geospatial metadata
Getting involved
Mailing List
Feel welcome to join the discussion and development mailing list:
TODO
- extract more of the specifics from Geodata Metadata Requirements. (This has changed a lot from the original version in the history & current version which has data sets differentiated from data sources, which may be files or databases or services)
- update docs on Geodata Metadata Model
- draw some UML to appease people?
Information Model
Core Model
Dublin Core
ISO19115
FGDC
References
- Dublin Core lite for Geo
- OGC Catalog Services 2 Specification 6.3.3, Core returnable properties
- iGeoResourceInfo class in uDig
- GeodataCommons Metadata Whitepaper
Query Interface
OAI-PMH
The Harvesting Protocol (version 2.0) specification together with Implementation Guidelines
Following are specific guidelines for a minimal OAI-PMH implementation of a so called 'data provider' using only the mandatory 'unqualified' Dublin Core (DC):
- Only three operations (verbs) are needed: Identify, ListMetadataFormats and ListRecords.
- Following operations are not required (initially): ListIdentifiers, ListSets, GetRecord.
- No incremental harvesting (resumption process for ListXxx operations with more than 1000 records)
- No compression as defined in the OAI-PMH spec. (compression at lower http level still possible)
- Date granularity may be 'day' not seconds (YYYY-MM-DD)
- Keeping track of deleted record may not be supported (deletedRecord=no)
- Mandatory DC supported as data model is sufficient for a start but with specific semantics (e.g. coverage, relation) (see also example below):
- dc:description contains dct:abstract
- dc:coverage contains bounding box encoding as defined in http://georss.org/simple.html#Box
- dc:date means in fact dct:modified
- dc:relation is filled in with dclite4g:onLineSrc. If dc:type='service' dct:hasPart can be derived from GetCapabilities.
Additional bounding box query property for ListRecords.
Others
References
- OWSCat
- Simple Catalog Interface - links to articles, etc
See Also
- http://www.geometa.info/ - German geospatial data search service using dclite4g + OAI-PMH.