curl --request GET \
  --url https://api.rivermarkets.com/v1/prices/{river_id} \
  --header 'x-api-key: <api-key>'

{
  "river_id": 123,
  "exchange": "<string>",
  "type": "candlesticks",
  "candlesticks": [
    {
      "timestamp": 123,
      "open": 123,
      "high": 123,
      "low": 123,
      "close": 123,
      "volume": 123
    }
  ],
  "history": [
    {
      "timestamp": 123,
      "price": 123
    }
  ]
}