Allow the ability to re-order designs

Problem to solve

Currently, designs are presented ordered by their created date. This prevents users from ordering the designs in a way that makes sense (e.g. to show flows or progressions through the UI).

Further details

The manual sort order can be re-ordered by anyone with edit access to the issue (just like anyone can edit a description on an issue) but the order is saved and not altered until manually changed again.

Prototype by @jareko

https://codepen.io/jareko999/full/BaaRYog

Documentation

• Design management documentation should be updated

Proposal

We would like to allow certain users to be able to re-order the designs, manually. This new order would be preserved when another user views the designs.

When new designs are uploaded, they will be inserted at the end of the list, not the beginning.

Backend Planning Comments

MR Breakdown

@toupeira:

• 1 MR to add the new DB column
• 1 MR to add a new GraphQL endpoint to reorder a design

@.luke:

• Database migration (uniquely constrained on issue_id)
• Model property (a unique constraint on new order property and issue_id)
• Data migration to set order properties on existing designs according to existing sort
• New update_design permission defined (would follow the existing permissions for create_design and destroy_design) and exposed on DesignPermissions GraphQL type
• Service for setting order
  • It would accept these arguments:
    • design_id
    • new_index
    • old_index - sanity check. Service will return an error if this doesn't match current index of design
  • It would return an error if the user does not have update_design (new permission added above) on the design
  • It would return the design that was updated
• Change to DesignsFinder to use ordering scope
• Expose order in GraphQL DesignType
• GraphQL mutation for setting order
  • Would authorize the user has update_design (new permission added above) on the design

Proposed GraphQL mutation schema:

designManagementDesignSetIndex(input: { design_id:, new_index:, old_index: }) {
  designCollection {
    ...
  }
  errors
}

Testing Activity

@toupeira :

If a custom order is present:

• Order should be kept if designs in the beginning/middle/end are deleted
• Newly added designs should be inserted at the end (or at the beginning?)

If a custom order is not present:

• Adding/deleting designs should behave as before

@.luke: Unit tests:

• Service
• DesignFinder changes
• GraphQL Type changes
• GraphQL mutation(s)

Request spec:

• GraphQL mutation(s)

All tests including permissions, handling bad data

Security Testing

@.luke:

• re-use an existing permission.