InfluxDB + Grafana：按时间排列的状态代码

Question

我正在尝试按时间在 Grafana 中显示 HTTP 状态代码。 数据像这样存储在 InfluxDB 中（简化）：

# time,status,bytesize
2024-04-27 11:24:00, 404,100
2024-04-28 01:24:00, 200,100
...

目前我使用SQL进行查询：

SELECT $__dateBin(time) AS time,
COUNT(CASE WHEN "status" BETWEEN 200 AND 299 THEN 1 END) AS "2xx",
COUNT(CASE WHEN "status" BETWEEN 400 AND 499 THEN 1 END) AS "4xx",
COUNT(CASE WHEN "status" >= 500 THEN 1 END) AS "5xx"
FROM http_requests
GROUP BY $__dateBin(time)

这会产生以下图表：

如您所见，值显示正确，但点是直接连接的，并且图形不会返回到基线 (0)。

我该如何解决这个问题？

Answer 1

我能够通过利用 InfluxDB 的 date_bin_gapfill 函数来实现空行。它可以与 Grafana 中的

$__interval

变量一起使用：

SELECT
  date_bin_gapfill($__interval, time) as _time,
  COUNT(CASE WHEN "status" BETWEEN 200 AND 299 THEN 1 END) AS "2xx",
  COUNT(CASE WHEN "status" BETWEEN 400 AND 499 THEN 1 END) AS "4xx",
  COUNT(CASE WHEN "status" >= 500 THEN 1 END) AS "5xx"
FROM "http_requests"
WHERE
    time >= $__timeFrom
    AND time <= $__timeTo
GROUP BY _time, status
ORDER BY _time

然后我必须选择用 0 插入缺失值的选项：

这使得图表看起来符合预期。