Removed half of the monitor plugins (#6224)

scripts/callbacks/minute/system/influxdb_checks.lua

@@ -0,0 +1,35 @@
+--
+-- (C) 2019-21 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+package.path = dirs.installdir .. "/scripts/lua/modules/timeseries/?.lua;" .. package.path
+
+local ts_utils = require "ts_utils_core"
+local alerts_api = require "alerts_api"
+local alert_consts = require "alert_consts"
+local influxdb_export_api = require "influxdb_export_api"
+    
+-- ##############################################
+
+if influxdb_export_api.isInfluxdbEnabled() then
+    -- Defines an hook which is executed every minute
+    local last_error = ntop.getCache("ntopng.cache.influxdb.last_error")
+
+    -- Note: last_error is automatically cleared once the error is gone
+    if(not isEmptyString(last_error)) then
+        local influxdb = ts_utils.getQueryDriver()
+
+        local alert_type = alert_consts.alert_types.alert_influxdb_error.new(
+            last_error
+        )
+
+        alert_type:set_score_error()
+        alert_type:set_granularity(alert_consts.alerts_granularities.min)
+
+        alert_type:store(alerts_api.systemEntity())
+    end
+end
+
+-- ##############################################