subscriptions_api.ex

mutation do
  field :submit_comment, :comment do
    arg :repo_fullname, non_null(:string)
    arg :content, non_null(:string)

    resolve fn args, _ ->
      comment = # create comment
      {:ok, comment}
    end
  end
end

subscription do
  field :comment_added, :comment do
    arg :repo_fullname, non_null(:string)

    trigger :submit_comment do
      # filter fn comment, args ->
      #   comment.repository_name == args.repo_fullname
      # end
      subscription_key fn args ->
        args.repo_fullname
      end
      mutation_key fn comment ->
        comment.repository_name
      end
    end

    resolve fn message, _, _ ->
      {:ok, message}
    end
  end
end