Notification templates allows you to change the default notification messages.
You can modify the content and format of notification messages. For example, you can customize the content to show only specific information or adjust the format to suit a particular contact point, such as Slack or Email.
Instead, you should [use annotations or labels](ref:template-annotations-and-labels) to add information directly to the alert, ensuring it's also visible in the alert state and alert history within Grafana. You can then print the new alert annotation or label in notification templates.
This page provides various examples illustrating how to template common notification messages. For more details about notification templates, refer to:
Notification templates can access the [notification data](ref:reference-notification-data) using the dot (`.`). The following examples demonstrate some basic uses of the [template language](ref:language).
For instance, to check if there are common labels (`.CommonLabels`) for all alerts in the notification, use `if`:
```go
{{ define "custom_message" -}}
{{ if .CommonLabels }}
Alerts have common labels
{{ else }}
There are no common labels
{{ end }}
{{ end }}
```
To iterate on the alerts in the notification and print a specific label, use `range` and `index`:
```go
{{ define "custom_message" -}}
{{ range .Alerts }}
The name of the alert is {{ index .Labels "alertname" }}
{{ end }}
{{ end }}
```
Alternatively, you can use the `.` notation to print the value of the key.
Here's an example that displays the summary and description annotations for each alert in the notification.
```go
{{ define "custom.alerts" -}}
{{ len .Alerts }} alert(s)
{{ range .Alerts -}}
{{ template "alert.summary_and_description" . -}}
{{ end -}}
{{ end -}}
{{ define "alert.summary_and_description" }}
Summary: {{.Annotations.summary}}
Status: {{ .Status }}
Description: {{.Annotations.description}}
{{ end -}}
```
In this example:
- A template (`alert.summary_and_description`) is defined to print the `summary`, `status`, and `description` of one [alert](ref:reference-alert).
- The main template `custom.alerts` iterates the list of alerts (`.Alerts`) in [notification data](ref:reference-notification-data), executing the `alert.summary_and_description` template to print the details of each alert.
Summary: The database server db1 has exceeded 75% of available disk space.
Status: firing
Description: This alert fires when a database server is at risk of running out of disk space. You should take measures to increase the maximum available disk space as soon as possible to avoid possible corruption.
Summary: The web server web1 has been responding to 5% of HTTP requests with 5xx errors for the last 5 minutes.
Status: resolved
Description: This alert fires when a web server responds with more 5xx errors than is expected. This could be an issue with the web server or a backend service.
```
## Print firing and resolved alerts
The following example is similar to the previous one, but it separates firing and resolved alerts.
```go
{{ define "custom.firing_and_resolved_alerts" -}}
{{ len .Alerts.Resolved }} resolved alert(s)
{{ range .Alerts.Resolved -}}
{{ template "alert.summary_and_description" . -}}
{{ end }}
{{ len .Alerts.Firing }} firing alert(s)
{{ range .Alerts.Firing -}}
{{ template "alert.summary_and_description" . -}}
{{ end -}}
{{ end -}}
{{ define "alert.summary_and_description" }}
Summary: {{.Annotations.summary}}
Status: {{ .Status }}
Description: {{.Annotations.description}}
{{ end -}}
```
Instead of `.Alerts`, the template accesses `.Alerts.Firing` and `.Alerts.Resolved` separately to print details for each alert.
Summary: The database server db1 has exceeded 75% of available disk space.
Status: resolved
Description: This alert fires when a database server is at risk of running out of disk space. You should take measures to increase the maximum available disk space as soon as possible to avoid possible corruption.
1 firing alert(s)
Summary: The web server web1 has been responding to 5% of HTTP requests with 5xx errors for the last 5 minutes.
Status: firing
Description: This alert fires when a web server responds with more 5xx errors than is expected. This could be an issue with the web server or a backend service.
```
## Print common labels and annotations
This example displays only the labels and annotations that are common to all alerts in the notification.
Alert annotations: {{ len .Annotations.SortedPairs }}
{{ range .Annotations.SortedPairs -}}
- {{ .Name }} = {{ .Value }}
{{ end -}}
{{ end -}}
```
In this example:
- The `custom.alert_labels_and_annotations` template iterates over the list of resolved and firing alerts, similar to previous examples. It then executes `alert.labels_and_annotations` for each alert.
- The `alert.labels_and_annotations` template prints all the alert labels and annotations by accessing `.Labels.SortedPairs` and `.Annotations.SortedPairs`.
- summary = The database server db1 has exceeded 75% of available disk space.
- description = This alert fires when a database server is at risk of running out of disk space. You should take measures to increase the maximum available disk space as soon as possible to avoid possible corruption.
1 firing alert(s)
Alert labels: 4
- alertname = web_server_http_errors
- grafana_folder = server_alerts
- server = web1
- team = server_admin
Alert annotations: 2
- summary = The web server web1 has been responding to 5% of HTTP requests with 5xx errors for the last 5 minutes.
- description = This alert fires when a web server responds with more 5xx errors than is expected. This could be an issue with the web server or a backend service.
```
## Print URLs for runbook and alert data in Grafana
Note that the following example works only for Grafana-managed alerts. It displays some [alert data](ref:reference-alert) such as `DashboardURL`, `PanelURL`, and `SilenceURL`, which are exclusive to Grafana-managed alerts.
You can include a link to a dashboard or panel in your alert notifications. This is useful when the alert rule is created from a dashboard panel or monitors a target visualized in an existing dashboard.
Including a dashboard link in the notification helps responders quickly navigate to the relevant context for investigation.
Use one of the following methods to include a dashboard link with the correct time range in the alert notification:
1. You can [link the alert rule to a panel](ref:link-alert-rules-to-panels). This includes the dashboard and panel URLs via `{{.Alert.DashboardURL}}` and `{{.Alert.PanelURL}}`.
These URLs include a time range based on the alert’s timing:
-`from`: One hour before the alert started.
-`to`: The current time if the alert is firing, or the alert’s end time if resolved.
1. Alternatively, you can use a custom annotation to set the dashboard URL and build the full URL using the `from` and `to` query parameters derived from `{{.Alert.StartsAt}}` and `{{.Alert.EndsAt}}`.
To use this template, define a custom annotation named `MyDashboardURL` that contains the base dashboard URL without `from` and `to` parameters. For example: `http://localhost:3000/d/uiyahbsdaubsd`.
The [custom payload option](ref:custom-payload-webhook) in the webhook contact point allows you to customize the payload of webhook notifications using a custom template.
The following example generates a custom JSON payload by executing other templates with `tmpl.Exec`, and using functions like `coll.Dict` and `data.ToJSON` to process and format JSON data.
