Alert not resetting when using count()


I’m trying to alert when I receive nginx errors. I have the following script, which works except the alert never resets when the errors drop to zero.

var data = batch
      |query('SELECT * FROM "telegraf"."autogen"."nginx_access_log"')
      |where(isPresent("@fields_request") AND int("@fields_status") > 499)
      |eval(lambda: "@fields_request").as('request').tags('request').keep()
      |eval(lambda: "@fields_status").as('status').tags('status').keep()

var alert = data
            .message("{{ index .Tags "host" }} is {{ .Level }}: ({{ index .Fields "status_count" }}) HTTP {{ index .Tags "status" }} {{ index .Tags "request" }}")
            .warn("status_count" > 0)

I understand that count won’t return zero if no data is received. I also tried a suggested reverse deadman script but that dropped all the tags I was using in my message and always produces a “CRITICAL” level rather than a warning.

Anyone have any suggestions?