[super] Related (Stuff) Extension

[rgrp]

This is a reworking of the existing apps extension.

Initial proposal at ​http://wiki.ckan.org/Proposals#Apps_in_CKAN and ​http://wiki.ckan.org/Proposals#References.2FLinks_in_CKAN

Naming

What do we call this extension?

• related
  • RP best IMO but perhaps too close to separate relationships concept?
• relatedstuff
• links
• references

Proposal

"Related Stuff": Apps as in an application (website/service/tool) that uses this dataset (as in Apps and Ideas extension)

• This case seems a general example of wanting to link some external thing to a dataset (e.g. this policy paper refs this dataset, this application uses this dataset, this visualization is built on this dataset cf ​http://lists.okfn.org/pipermail/ckan-discuss/2011-August/001607.html)

Implementation

New table named Related with following structure

|| id (int) || type || title || description (markdown) || image_id || owner_id || url || created (timestamp)

type = Idea

App

API

Visualization

Post

Paper

News Article

• Suggest we make this a ckan.ini config option (comma separated ...?)

• image: ?? Depends where we store images. Simplest option would be to change to image_url and leave it to users to have already uploaded an image somewhere. If not we need to support image uploading and storage. See #1692 (add image attribute to datasets and groups) for more discussion.
• owner_id = user_id or creating user (see authorization below)

Related2Dataset (note that related_id, dataset_id tuple should be unique). This allows for m2m connections. If a given related item is only with one dataset this could be simplified.

|| id || dataset_id || related_id

Url

• /dataset/{dataset-name}/related/{related-item-id}/{related-item-title-stringified}
  • If a reference item could exist in its own right (and perhaps refer to multiple datasets then it should get its own url at e.g. /related/{id}

Authorization

Addition of related item be considered orthogonal to datasets (and hence with separate authorization i.e. i can add the info that site X uses dataset Y without needing permission to edit dataset Y).

Thus any logged in user could add a Related item. We set the owner of the related item to creating user and going forward only that user or a sysadmin can update or delete.

NB: we could have a system where datasets owners have to approve related items before they show up next to their dataset. This would add substantial complexity so I propose we leave out of phase 1.