Store workspace assignments as properties

[jri]

Currently the workspace assignments are part of the graph itself, actually associations of type Aggregation.
This results in vicious circles in conjunction with the new Workspace ACLs (see #592).

Workspace assignments should be stored as DB properties instead. Thus a topic's/association's workspace assignment can be determined without fetching the topic/association in advance. The vicious circles vanish.

[Jörg Richter]

Store workspace assignment as property (#668).

Thus a topic's/association's workspace assignment can be determined without fetching the topic/association in advance.

BREAKING CHANGES

Workspace API

1 method has changed:

Topic getAssignedWorkspace(long id)

It takes a topic/association ID instead of a DeepaMehtaObject.

1 method is added:

Topic createWorkspace(String name, String uri, String workspaceTypeUri)

So, the workspace type URI must be passed when creating a workspace.
The former 2 createWorkspace() methods are dropped.

See #668.

• Changeset: 920f5794cd9a6f977d5885525b01477b10252fcf
• URL: ​https://github.com/jri/deepamehta/commit/920f5794cd9a6f977d5885525b01477b10252fcf

[jri]

Realized in workspace-acl branch. Will be available in DM 4.5