GNIP-67: GeoNode CSW-T

[tomkralidis]

Overview

GeoNode's core CSW support is realized by pycsw. Alternate CSW endpoints can be configured with the underlying interaction being HTTP via the CSW request/response mechanisms.

CSW-T is a profile of CSW which allows transactions to be performed against a catalogue (insert/update/delete). pycsw provides full CSW (core/basic and transactional) but CSW-T is disabled to facilitate transactional workflows via GeoNode proper.

Allow for CSW-T based functionality directly against GeoNode/Django models.

This GNIP will enable GeoNode's underlying pycsw support to provide CSW-T capability directly against the GeoNode/Django models.

Proposed By

@tomkralidis

Assigned to Release

2.5.x

Motivation

Currently, pycsw as integrated in GeoNode provides a one-way/outbound/readonly endpoint with direct read access from the GeoNode DB. Enhancing with CSW-T will allow GeoNode to support a richer harvesting workflow via CSW-T of numerous resource types (WMS, WFS, WCS, WAF, etc.)

Proposal

Enable pycsw's GeoNode backend to support CSW-T functionality.

Implementation

Concepts

pycsw's harvesting approach is to create a generic Record object which is managed as a metadata record in a given metadata repository. This covers the metadata record workflow.

For the services (WMS, WFS, WCS, SOS, WPS, etc.) workflow, pycsw inserts 1+n Record objects into the repository. For example, if a WMS has 66 layers, 67 Record objects are inserted (1 as a service metadata record, and 66 layer metadata records).

pycsw

pycsw's backend architecture allows for using a default model and/or binding to an alternate model via configuration of field mappings with some detailed semantics. pycsw's GeoNode repository plugin contains the required functionality as part of the pycsw.core.repository.Repository model. The insert, update, delete functions will be added to pycsw.plugins.repository.geonode.geonode_.GeoNodeRepository to insert/update/delete metadata records seamlessly. Translation between core pycsw harvesting and GeoNode repository models is required.

Issues

• which resource types to support?
• workflow
• how results are realized on GeoNode UI

[pjdufour]

What is CSW-T? Sorry, I've never heard of it before. Could you provide some reference links (Google doesn't return good results).

[tomkralidis]

@pjdufour updated GNIP text for clarification.

[pjdufour]

So the big gain is for registering remote services in GeoNode?

[tomkralidis]

Remote services and resources (i.e. existing of standalone datasets, etc.)

[jj0hns0n]

@tomkralidis is this ready for 2.5?

[jj0hns0n]

@tomkralidis this can be closed as merged now right?

[kikislater]

Please re-open as it's not implemented !

[afabiani]

@ALL please, when creating a GNIP, other than the correct label it must:

• contain in the title the prefix GNIP-xx where xx is a progressive number == len(gnips) + 1
• update the https://github.com/GeoNode/geonode/wiki/GeoNode-Improvement-Proposals accordingly

[kikislater]

Do we need to wait pycsw PR with commits available here :
geopython/pycsw@master...tomkralidis:geonode-csw-t

before making a PR with these commits in Geonode :
master...tomkralidis:csw-t
?

[giohappy]

Is this issue still in progress?