wrk.method = "POST"
wrk.headers["Content-Type"] = "application/json"
wrk.headers["Accept"] = "application/json"

query = [[
  query books($ids: [Integer]) {
    books(ids: $ids) {
        id
        name
        price
      }
    }
  }
]]
variables = [[
  "ids": [1,2,3,4]
]]
wrk.body ='{"query": "' .. string.gsub(query, '\n', '') .. '", "variables": {' .. string.gsub(variables, '\n', '') .. '} }'