View/edit epic at group level

• View epic at group level.
• This applies to any group (or subgroup).
• Everything below applies to a "subgroup" in general.
• View/edit the title. View/edit the description.
• Permissions for viewing + editing below.
• When in edit mode, the pencil does not appear.
• View the timestamp. View the creator and their avatar.
• Link to the creator, along with the tooltip.
• The page is associated at the group level of a group.
• No specified license for epics in this issue. That requirement is handled in https://gitlab.com/gitlab-org/gitlab-ee/issues/3731.
• Use & for epics. Must also update CE code per https://gitlab.com/gitlab-org/gitlab-ee/issues/3255#note_41593585.
• If breadcrumbs are implemented in this issue, then it should be clickable, per https://gitlab.com/gitlab-org/gitlab-ce/issues/38059.
• pencil icon tooltip copy Edit title and description

Permissions

• Private group:

  • Epics can be only viewed by group members.
  • Epics can only be created/edited by role group reporter or higher. (Editing means both title and description.)

• Internal group:

  • Epics can be viewed by any logged in user.
  • Epics can only be created/edited by role group reporter or higher. (Editing means both title and description.)

• Public group:

  • Epics can be viewed without any authentication.
  • Epics can only be created/edited by role group reporter or higher. (Editing means both title and description.)

• Epic creation is not in scope here.

• In other words, we expect users of open source projects to submit/create issues, but we do not expect them to create epics. Of course they should be able to view epics.

Important technical note

• The epic object should very likely be architected in the system as an issuable, since it will have many similar behaviors as issues / merge requests.
• From a product/feature perspective, we want epics as a first class citizen, to make it easier for users to use them in roadmap views.
• But from a tech perspective, there is a lot to be gained from re-using existing code/functionality. So much so that we should strongly consider changing certain designs for an epic if it means reducing effort cost and maintenance cost going forward.

Out of scope

• Navigation is out of scope. So you won't be able to access the page as a user. And you cannot create an epic. To test the feature, you have to populate the database manually and access it.

User Acceptance

• Some script (manual or automatic) to populate the database with an epic in a private group.
• Some script (manual or automatic) to populate the database with an epic in an internal group.
• Some script (manual or automatic) to populate the database with an epic in a public group.
• Validate viewing and editing with different roles in those three scenarios.
• Validate it works for all levels of subgroups.

Design