content: -- This file is part of the Wire Server implementation.
  --
  -- Copyright (C) 2022 Wire Swiss GmbH <opensource@wire.com>
  --
  -- This program is free software: you can redistribute it and/or modify it under
  -- the terms of the GNU Affero General Public License as published by the Free
  -- Software Foundation, either version 3 of the License, or (at your option) any
  -- later version.
  --
  -- This program is distributed in the hope that it will be useful, but WITHOUT
  -- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  -- FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
  -- details.
  --
  -- You should have received a copy of the GNU Affero General Public License along
  -- with this program. If not, see <https://www.gnu.org/licenses/>.
  
  module Wire.API.Federation.API.Common where
  
  import Data.Aeson
  import Data.OpenApi (ToSchema)
  import Imports
  import Test.QuickCheck
  import Wire.Arbitrary
  
  -- | This is equivalent to '()', but JSONifies to an empty object instead of an
  -- empty array. Returning an empty object gives us more flexibility, allowing
  -- us to expand the response without breaking compatibility.
  data EmptyResponse = EmptyResponse
    deriving stock (Eq, Show, Generic)
    deriving (Arbitrary) via (GenericUniform EmptyResponse)
  
  instance ToSchema EmptyResponse
  
  instance FromJSON EmptyResponse where
    parseJSON = withObject "EmptyResponse" . const $ pure EmptyResponse
  
  instance ToJSON EmptyResponse where
    toJSON EmptyResponse = object []
  