Querying the Bars API for DXCM with parameters {'start': '2016-07-21T00:00:00Z', 'end': '2016-07-21T23:59:59Z', 'timeframe': '1Min'} returns null bars: {"bars":null,"symbol":"DXCM","next_page_token":null}. For example, use curl 'https://data.alpaca.markets/v2/stocks/DXCM/bars?start=2016-07-21T00%3A00%3A00Z&end=2016-07-21T23%3A59%3A59Z&timeframe=1Min' -H "APCA-API-KEY-ID: $key_id" -H "APCA-API-SECRET-KEY: $secret_key" .
What is the meaning of null bars? I’ve also seen them when I query an instrument before its inception. The latter behavior is understandable, but is the DXCM hole on 2016-07-21 expected?
Replacing the start and end date with the previous day, 2016-07-20, yields bars normally. For example, use curl 'https://data.alpaca.markets/v2/stocks/DXCM/bars?start=2016-07-20T00%3A00%3A00Z&end=2016-07-20T23%3A59%3A59Z&timeframe=1Min' -H "APCA-API-KEY-ID: $key_id" -H "APCA-API-SECRET-KEY: $secret_key".
Furthermore, I am able to get daily DXCM data for 2016-07-21. curl 'https://data.alpaca.markets/v2/stocks/DXCM/bars?start=2016-07-21T00%3A00%3A00Z&end=2016-07-21T23%3A59%3A59Z&timeframe=1Day' -H "APCA-API-KEY-ID: $key_id" -H "APCA-API-SECRET-KEY: $secret_key" yields {"bars":[{"t":"2016-07-21T04:00:00Z","o":84.63,"h":84.63,"l":84.63,"c":84.63,"v":0,"n":0,"vw":0}],"symbol":"DXCM","next_page_token":null}.
Finally, I am able to get minutely data for AAPL on this date. For example, use curl 'https://data.alpaca.markets/v2/stocks/AAPL/bars?start=2016-07-21T00%3A00%3A00Z&end=2016-07-21T23%3A59%3A59Z&timeframe=1Min' -H "APCA-API-KEY-ID: $key_id" -H "APCA-API-SECRET-KEY: $secret_key".