APItools middleware to convert apibunny.com responses to JSON-LD

apibunny-middleware

return function(request, next_middleware)
  local response = next_middleware()
  
  if (response.headers['content-type'] == 'application/json') then
    local data = json.decode(response.body)
  
    if (data.mazes) then
      data['@context'] = 'http://www.hydra-cg.com/examples/maze'
      data['id'] = data.mazes[1].id
      data['@type'] = 'Maze'
      data['name'] = data.mazes[1].name
      
      for relation, value in pairs(data.mazes[1].links) do
        data[relation] = '/cells/' .. value
      end
      
      data.mazes = nil
      data.links = nil
    elseif (data.cells) then
      data['@context'] = 'http://www.hydra-cg.com/examples/maze'
      data['id'] = data.cells[1].id
      data['name'] = data.cells[1].name
      data['@type'] = data.cells[1].type:gsub("^%l", string.upper)
      
      for relation, value in pairs(data.cells[1].links) do
        if (relation == 'maze') then
          data[relation] = '/mazes/' .. value
        else
          data[relation] = value
        end
      end
      
      if (data.cells[1].exit_link) then
        data.exit = '/users/'
      end
      
      data.cells = nil
      data.links = nil      
    end
    
    response.body = json.encode(data)
    response.headers['content-type'] = 'application/ld+json'
  end
  
  return response
end