How can I achieve taxonomy workflow (allowed next states of taxonomy terms)?

Question

I have a vocabulary containing some terms for issues' states:

• Open
• In progress
• Closed

I want to be able to define allowed "next" states for each term. So that a user can only change:

• Open -> In progress
• In progress -> Open, or Closed
• Closed -> None

I am using Drupal 7.

Answer 1

I don't think there's a ready made solution for this. The maintainer of workbench_moderation has said that a goal is to collaborate with other workflow modules and made one module to rule them all, and one of the primary goals of that initiative is "workflows for non-node entities" but this is still a long way off and doesn't seem to be very far past the planning stages at this point.

So I think the closest you can get currently is the taxonomy_revision module but that just adds revisions and doesn't help in automating a workflow out of them, so you'll have to do some custom development on top of that.

Answer 2

Have you checked Workflow module ? Though workflow module allows the creation and assignment of arbitrary workflows to Drupal node types, but if you want only for vocabulary then probably you have to develop custom module only.