[BUG] Unable to generate top-level tags key

[Billy Cropley]

Describe the bug

OAS 3.1.0 supports a top-level tags object that allows optional "description" fields, but I've been unable to find a way to produce this when generating yaml from Rswag

Steps to Test or Reproduce

Ideally, this would work when providing the tags keyword either in a path block or top-level describe block for the api

path '/pets' do
    tags name: 'pet', description: 'Everything about your Pets'

or

describe 'Pets API' do
    tags name: 'pet', description: 'Everything about your Pets'

both of these result in a NoMethodError:

Failure/Error: tags name: 'pet', description: 'Everything about your Pets'

NoMethodError:
  undefined method `[]=' for nil:NilClass

            metadata[:operation][attr_name] = value
                                ^^^^^^^^^^^^^

Expected behavior

Output should be similar to:

info:
  title: "Pet Sample"
tags:
  - name: pet
    description: Everything about your Pets
  - name: store
    description: Access to Petstore orders
paths:
  "/pets":

Additional context

Sample JSON showing tags object

Sample yaml with tags:

Dependency versions

The version of are you using for:

• Rswag: 2.7.0
• RSpec: 3.1.0
• Rails: 6.1.7.3
• Ruby: 3.1.0
  (briefly tested with Rswag 2.10.1, issue remains)

Relates to which version of OAS (OpenAPI Specification)

• OAS2
• OAS3
• OAS3.1

[Billy Cropley]

for the time being I'm getting around this by manually adding them using a callback in my swagger_helper, a simplified example:

config.after do
  doc_tags = [{name: 'Pet', description: 'Everything about your pets'}]
  swagger_docs = config.instance_variable_get('@swagger_docs')

  swagger_docs.each do |_path, doc| 
    doc[:tags] = doc_tags
  end
end