collective.relationhelpers 1.0a1

An add-on for Plone

Helpers for dealing with relations in Plone.

To learn more about relations read https://training.plone.org/5/mastering-plone/relations.html

Features

Rebuild all relations

There is a form http://localhost:8080/Plone/@@rebuild_relations that rebuilds all relations.

It exports all valid reations from the relation-catalog, purges the relation-catalog (and the intid-catalog) and restores all valid relations.

It uses some helper methods that you can use in your own projects or upgrade-steps.

First import the api: from collective.relationhelpers import api as relapi

Dealing with all relations at once

Especially during migrations (e.g. between Archetypes and Dexteriy or from Python 2 to 3) you need to deal with relations.

These methods can help:

relapi.rebuild_relations()

Rebuild all relations using the same code as the form @@rebuild_relations

relapi.get_all_relations()

Get all relations as a list of dicts.

relapi.export_relations()

Export all relations as a json file all_relations.json in you buildout directory.

relapi.store_relations()

Export all relations and store them as a annotation on the portal IAnnotations(portal)['ALL_REFERENCES'].

relapi.cleanup_intids()

Purge all RelationValues and all references to broken objects from the IntId catalog.

relapi.get_relations_stats()

Log information on all existing relations

relapi.restore_relations(all_relations=None)

Recreate relations from a annotation on the portal or a list of dicts (e.g. restored from the json-file created by export_relations). This works fine for all kinds of relations, RelationList- or RelationChoice-fields (including the default field “Related Items”) as well as for linkintegrity-relations and relations between working-copies.

Dealing with relations on individual objects

relapi.link_objects(source, target, relationship)

Link objects: Create a relation between two objects using the specified relationship. From the parameter relationship the method will find out what kind of relationship you want to create (RelationChoice, RelationList) by inspecting the schema-field on the source-object. The method also works for linkintegrity-relations and relations between working-copies.

Example: To use the default-behavior plone.relateditems use the field-name relatedItems as relationship: relapi.link_objects(obj, anotherobj, 'relatedItems').

relapi.get_relations(obj, attribute=None, backrefs=False, fullobj=False)

Get a list of incoming or outgoing relation for a specific content object.

If you pass a attribute (i.e. the from_attribute of the relation) you can use it to get only specific relations.

The result is returned as a dict with the following values:

id: The id of the related or relating (for backreferences) object

href: The url of the object

title: The title

relation: The name of the relation (i.e. field).

fullobj: The obj (optional)

relapi.get_backrelations(obj, attribute=None, fullobj=False)

Wrapper for get_relations that only return backrelations.

Installation

Install collective.relationhelpers by adding it to your buildout:

[buildout]

...

eggs =
    collective.relationhelpers

and then running bin/buildout.

Contribute

• Issue Tracker: https://github.com/collective/collective.relationhelpers/issues

• Source Code: https://github.com/collective/collective.relationhelpers

Support

If you are having issues, please create a ticket.

License

The project is licensed under the GPLv2.

Contributors

• Philip Bauer, [e-mail]

Changelog

1.0a1 (2020-05-29)

• Initial release. [pbauer]