Dashboard: Enforce min dashboard refresh interval to 5 seconds per default (#23929)

Fixes #22493

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - **Removed PhantomJS**: PhantomJS was deprecated in [Grafana v6.4](https://grafana.com/docs/grafana/latest/guides/whats-new-in-v6-4/#phantomjs-deprecation) and starting from Grafana v7.0.0, all PhantomJS support has been removed. This means that Grafana no longer ships with a built-in image renderer, and we advise you to install the [Grafana Image Renderer plugin](https://grafana.com/grafana/plugins/grafana-image-renderer).
 - **Docker**: Our Ubuntu based images have been upgraded to Ubuntu [20.04 LTS](https://releases.ubuntu.com/20.04/).
+- **Dashboard**: A global minimum dashboard refresh interval is now enforced and defaults to 5 seconds.
 
 # 6.7.3 (2020-04-23)
 

conf/defaults.ini

@@ -230,9 +230,9 @@ snapshot_remove_expired = true
 # Number dashboard versions to keep (per dashboard). Default: 20, Minimum: 1
 versions_to_keep = 20
 
-# Minimum dashboard refresh interval. When set, this will restrict users to set the refresh interval of a dashboard lower than given interval. Per default this is not set/unrestricted.
+# Minimum dashboard refresh interval. When set, this will restrict users to set the refresh interval of a dashboard lower than given interval. Per default this is 5 seconds.
 # The interval string is a possibly signed sequence of decimal numbers, followed by a unit suffix (ms, s, m, h, d), e.g. 30s or 1m.
-min_refresh_interval =
+min_refresh_interval = 5s
 
 #################################### Users ###############################
 [users]

conf/sample.ini

@@ -229,9 +229,9 @@
 # Number dashboard versions to keep (per dashboard). Default: 20, Minimum: 1
 ;versions_to_keep = 20
 
-# Minimum dashboard refresh interval. When set, this will restrict users to set the refresh interval of a dashboard lower than given interval. Per default this is not set/unrestricted.
+# Minimum dashboard refresh interval. When set, this will restrict users to set the refresh interval of a dashboard lower than given interval. Per default this is 5 seconds.
 # The interval string is a possibly signed sequence of decimal numbers, followed by a unit suffix (ms, s, m, h, d), e.g. 30s or 1m.
-;min_refresh_interval =
+;min_refresh_interval = 5s
 
 #################################### Users ###############################
 [users]

docs/sources/installation/configuration.md

@@ -510,7 +510,7 @@ Number dashboard versions to keep (per dashboard). Default: `20`, Minimum: `1`.
 
 > Only available in Grafana v6.7+.
 
-When set, this will restrict users to set the refresh interval of a dashboard lower than given interval. Per default this is not set/unrestricted.
+This will restrict users to set the refresh interval of a dashboard lower than given interval. Per default this is 5 seconds.
 The interval string is a possibly signed sequence of decimal numbers, followed by a unit suffix (ms, s, m, h, d), e.g. `30s` or `1m`.
 
 ## [dashboards.json]

docs/sources/installation/upgrading.md

@@ -244,3 +244,7 @@ change the `[security]` setting `cookie_secure` to `true` and use HTTPS when `co
 ### PhantomJS removed
 
 PhantomJS was deprecated in [Grafana v6.4](https://grafana.com/docs/grafana/latest/guides/whats-new-in-v6-4/#phantomjs-deprecation) and starting from Grafana v7.0.0, all PhantomJS support has been removed. This means that Grafana no longer ships with a built-in image renderer, and we adwise you to install the [Grafana Image Renderer plugin](https://grafana.com/grafana/plugins/grafana-image-renderer).
+
+### Dashboard minimum refresh interval enforced
+
+A global minimum dashboard refresh interval is now enforced and defaults to 5 seconds. Read more [here]({{< relref "configuration/#min-refresh-interval" >}}) about this setting.

pkg/setting/setting.go

@@ -768,7 +768,7 @@ func (cfg *Cfg) Load(args *CommandLineArgs) error {
 	// read dashboard settings
 	dashboards := iniFile.Section("dashboards")
 	DashboardVersionsToKeep = dashboards.Key("versions_to_keep").MustInt(20)
-	MinRefreshInterval, err = valueAsString(dashboards, "min_refresh_interval", "")
+	MinRefreshInterval, err = valueAsString(dashboards, "min_refresh_interval", "5s")
 	if err != nil {
 		return err
 	}