search

Esri / geoportal-server

Geoportal Server is a standards-based, open source product that enables discovery and use of geospatial resources including data and services.
https://gptogc.esri.com/geoportal
Apache License 2.0
245 stars 149 forks source link

Transform metadata from one standard to another upon publishing #182

Open eggwhites opened 9 years ago

eggwhites commented 9 years ago

Transform metadata to another standard upon publishing. This is the ability to chain transformations – i.e., 19115:2003 documents into the new ISO 19115-1, or FGDC to into ISO 19115-2 metadata.

valentinedwv commented 9 years ago

This could effect the quality of the metadata being produced. Newer standards may be a bit tighter, so the transformation chain may need to improved to be sure documents produced are compliant

mhogeweg commented 9 years ago

that is a generic concern with transforming between metadata specifications. even from the verbose metadata specs like FGDC/ISO to the 'brief' open data specs leads to issues as for example in the US, those open data specs include agency information that has never been captured in geospatial metadata.

@eggwhites can you elaborate on the purpose of this enhancement? what are the specific cases where this is useful and what about the loss of information issue?

eggwhites commented 9 years ago

In our experience, most organizations that deploy geoportals have metadata in one or more profiles and they use the geoportal's indexing capabilities to have a consistent search experience through the geoportal search interface or its REST API.

This enhancement is for a different use case: organizations that have metadata in one or more profiles but want to expose the metadata XML in one specific profile. Doing so may support a more consistent discovery experience - especially if the organization wants to search on very specific XML elements instead of general concepts - and can supports interoperability with other systems that consume the metadata XML.

Yes, transformations are rarely perfect between standards so there is the possibility of loss of information. But let's say the transformations are very good. The gain here is in the simplicity of client applications that would only have to ingest/display one type of metadata XML because the geoportal - which already can handle a variety of profiles - is doing the work to make the documents consistent.

smrgeoinfo commented 9 years ago

The use case that interests me is automating connections between client applications and data sources, particular web-service-based distributions. From that point of view, the catalog service must provide uniform metadata conforming to a profile that the client applications understand. This requires that the catalog service verify that its output metadata records match the profile it advertises.

zguo commented 8 years ago

Actually the mechanism for transform from one format to another is in place in geoportal, we just did one that will harvest oai_dc flavor and transform into DC, it involve update schemas.xml, definition.xml and you'll have to author an transformer, in our case the oai_dc to dc transformer is quite simple.

mhogeweg commented 8 years ago

would be good if you can create a wiki page for that process and example