Notification template reference

By default, Grafana provides predefined templates to format notification messages.

You can also customize your notifications with custom templates, which are based on the Go template language.

This documentation lists the data available for use in notification templates.

Notification Data

In notification templates, dot (.) is initialized with the following data:

Name	Type	Description
`Receiver`	string	The name of the contact point sending the notification
`Status`	string	The status is `firing` if at least one alert is firing, otherwise `resolved`.
`Alerts`	[]Alert	List of all firing and resolved alerts in this notification.
`Alerts.Firing`	[]Alert	List of all firing alerts in this notification.
`Alerts.Resolved`	[]Alert	List of all resolved alerts in this notification.
`GroupLabels`	KV	The labels that group these alerts in this notification based on the `Group by` option.
`CommonLabels`	KV	The labels common to all alerts in this notification.
`CommonAnnotations`	KV	The annotations common to all alerts in this notification.
`ExternalURL`	string	A link to Grafana, or the Alertmanager that sent this notification if using an external Alertmanager.

It’s important to remember that a single notification can group multiple alerts to reduce the number of alerts you receive. Alerts is an array that includes all the alerts in the notification.

Here’s an example that prints all available notification data from dot (.):

{{ define "custom_template" }}
  {{ .Receiver }}
  {{ .Status }}
  There are {{ len .Alerts }} alerts
  There are {{ len .Alerts.Firing }} firing alerts
  There are {{ len .Alerts.Resolved }} resolved alerts
  {{ .GroupLabels }}
  {{ .CommonLabels }}
  {{ .CommonAnnotations }}
  {{ .ExternalURL }}
{{ end }}

Alert

Alert contains data for an individual alert:

Name	Type	Description
`Status`	string	Firing or resolved.
`Labels`	KV	The labels for this alert.
`Annotations`	KV	The annotations for this alert.
`StartsAt`	Time	The time the alert fired
`EndsAt`	Time	Only set if the end time of an alert is known. Otherwise set to a configurable timeout period from the time since the last alert was received.
`GeneratorURL`	string	A link to Grafana, or the source of the alert if using an external alert generator.
`Fingerprint`	string	A unique string that identifies the alert.

Grafana-managed alerts include these additional properties:

Name	Type	Description
`DashboardURL`	string	A link to the Grafana Dashboard if the alert has a Dashboard UID annotation.
`PanelURL`	string	A link to the panel if the alert has a Panel ID annotation.
`SilenceURL`	string	A link to silence the alert.
`Values`	KV	The values of all expressions, including Classic Conditions.
`ValueString`	string	A string that contains the labels and value of each reduced expression in the alert.

This example iterates over the list of firing and resolved alerts (.Alerts) in the notification and prints the data for each alert:

{{ define "custom_template" }}
{{ range .Alerts }}
  {{ .Status }}
  {{ .Labels }}
  {{ .Annotations }}
  {{ .StartsAt }}
  {{ .EndsAt }}
  {{ .GeneratorURL }}
  {{ .Fingerprint }}

  {{/* Only available for Grafana-managed alerts */}}
  {{ .DashboardURL }}
  {{ .PanelURL }}
  {{ .SilenceURL }}
  {{ .Values }}
  {{ .ValueString }}
{{ end }}
{{ end }}

KV

KV is a set of key value pairs, where each key and value is a string.

Similarly to accessing variable properties, you can use . to retrieve the value of a value. For example:

{{ define "custom_template" }}
  {{ .CommonLabels.grafana_folder }}
{{ end }}

If a KV happens to contain numbers or bools then these are string representations of the numeric or boolean value.

Additionally, KV provides methods to sort the pairs, remove keys, and iterate over just the keys or values:

Method name	Description	Arguments	Returns
SortedPairs	Returns a sorted list of key/value pairs.		Pairs
Remove	Returns a copy of the KV with the keys removed	[]string	KV
Names	Return the names of the label names		[]string
Values	Return a list of the values		[]string

Here’s an example of using these methods:

{{ define "custom_template" }}
  {{ .CommonLabels.SortedPairs }}
  {{ .CommonLabels.Names }}
  {{ .CommonLabels.Values }}
  {{ .CommonLabels.Remove (stringSlice "grafana_folder") }}
{{ end }}

Time

Some template functions and properties return a Time object, which refers to the type Time in Go’s time package.

When accessing a Time object, you can use various Time functions in your templates as follows.

{{ define "custom_template" }}
  {{ range .Alerts }}
    {{ .StartsAt  }}
    {{ .StartsAt.Add 6000000000000  }}
    {{ .StartsAt.Add -6000000000000  }}
    {{ .StartsAt.AddDate 1 0 0  }}
    {{ .StartsAt.Year   }}/{{ .StartsAt.Month   }}/{{ .StartsAt.Day   }}
    {{ .StartsAt.Hour   }}:{{ .StartsAt.Minute   }}:{{ .StartsAt.Second   }}
    {{ .StartsAt.YearDay   }}-{{ .StartsAt.Weekday   }}
    {{ .StartsAt.Unix }} {{ .StartsAt.UnixMilli }}
  {{ end}}
{{ end }}

Functions

Functions can perform actions in templates such as transforming or formatting data.

Note that the functions provided by Go’s template language, such as index, and, printf, and len, are available, along with many others.

In addition, the following functions are also available for templating notifications:

Name	Arguments	Returns	Description
`title`	string	string	Capitalizes the first character of each word.
`toUpper`	string	string	Returns all text in uppercase.
`toLower`	string	string	Returns all text in lowercase.
`trimSpace`	string	string	Removes leading and trailing white spaces.
`match`	pattern, text	boolean	Matches the text against a regular expression pattern.
`reReplaceAll`	pattern, replacement, text	string	Replaces text matching the regular expression.
`join`	sep string, s []string	string	Concatenates the elements of s to create a single string. The separator string sep is placed between elements in the resulting string.
`safeHtml`	string	string	Marks string as HTML not requiring auto-escaping.
`stringSlice`	…string	string	Returns the passed strings as a slice of strings. auto-escaping.
`date`	string, Time	string	Format a time in the specified format. For format options, refer to Go’s time format documentation.
`tz`	string, Time	Time	Returns the time in the specified timezone, such as `Europe/Paris`. For available timezone options, refer to the list of tz database time zones.

Here’s an example using some functions to format text:

{{ define "custom_template" }}
  {{ title "hello, world!" }}
  {{ toUpper "Hello, world!" }}
  {{ toLower "Hello, world!" }}
  {{ trimSpace "Hello, world!" }}
  {{ match "a.*" "abc" }}
  {{ reReplaceAll "localhost:(.*)" "example.com:$1" "localhost:8080" }}
  {{ join "-" (stringSlice "a" "b" "c") }}
  {{ safeHtml "<b>Text</b>"}}
  {{ stringSlice "a" "b" "c" }}
{{ end }}

date and tz can format times. For example, to print the time an alert fired in the format 15:04:05 MST:

{{ define "custom_template" }}
  {{ range .Alerts }}
    {{ .StartsAt | date "15:04:05 MST" }}
  {{ end}}
{{ end }}

You can then use tz to change the timezone from UTC to local time, such as Europe/Paris.

{{ define "custom_template" }}
  {{ range .Alerts }}
    {{ .StartsAt | tz "Europe/Paris" }}
    {{ .StartsAt | tz "Europe/Paris" | date "15:04:05 MST" }}
  {{ end}}
{{ end }}

2024-10-30 21:01:45.227 +0100 CET
21:01:45 CET

Differences with annotation and label templates

In the alert rule, you can also template annotations and labels to include additional information. For example, you might add a summary annotation that displays the query value triggering the alert.

Annotation and label templates add relevant information to individual alert instances, while notification templates inform about a group of alert instances.

Since both types of templates operate in distinct contexts, the functions and variables available in annotation and label templates differ from those used in notification templates.