(Optional) Configuring alert manager to output JSON to Amazon SNS - Amazon Managed Service for Prometheus

(Optional) Configuring alert manager to output JSON to Amazon SNS

You can configure alert manager to send alerts in JSON format, so that they can be processed downstream from Amazon SNS in AWS Lambda or in webhook-receiving endpoints. The default template provided with the Amazon Managed Service for Prometheus alert manager outputs the message payload in a text list format, which might not be easy to parse. Instead of using the default template, you can define a custom template to output the message contents in JSON, making it easier to parse in downstream functions.

To output messages from alert manager to Amazon SNS in JSON format, update your alert manager configuration to contain the following code inside your template_files root section:

default_template: |
   {{ define "sns.default.message" }}{{ "{" }}"receiver": "{{ .Receiver }}","status": "{{ .Status }}","alerts": [{{ range $alertIndex, $alerts := .Alerts }}{{ if $alertIndex }}, {{ end }}{{ "{" }}"status": "{{ $alerts.Status }}"{{ if gt (len $alerts.Labels.SortedPairs) 0 -}},"labels": {{ "{" }}{{ range $index, $label := $alerts.Labels.SortedPairs }}{{ if $index }}, {{ end }}"{{ $label.Name }}": "{{ $label.Value }}"{{ end }}{{ "}" }}{{- end }}{{ if gt (len $alerts.Annotations.SortedPairs ) 0 -}},"annotations": {{ "{" }}{{ range $index, $annotations := $alerts.Annotations.SortedPairs }}{{ if $index }}, {{ end }}"{{ $annotations.Name }}": "{{ $annotations.Value }}"{{ end }}{{ "}" }}{{- end }},"startsAt": "{{ $alerts.StartsAt }}","endsAt": "{{ $alerts.EndsAt }}","generatorURL": "{{ $alerts.GeneratorURL }}","fingerprint": "{{ $alerts.Fingerprint }}"{{ "}" }}{{ end }}]{{ if gt (len .GroupLabels) 0 -}},"groupLabels": {{ "{" }}{{ range $index, $groupLabels := .GroupLabels.SortedPairs }}{{ if $index }}, {{ end }}"{{ $groupLabels.Name }}": "{{ $groupLabels.Value }}"{{ end }}{{ "}" }}{{- end }}{{ if gt (len .CommonLabels) 0 -}},"commonLabels": {{ "{" }}{{ range $index, $commonLabels := .CommonLabels.SortedPairs }}{{ if $index }}, {{ end }}"{{ $commonLabels.Name }}": "{{ $commonLabels.Value }}"{{ end }}{{ "}" }}{{- end }}{{ if gt (len .CommonAnnotations) 0 -}},"commonAnnotations": {{ "{" }}{{ range $index, $commonAnnotations := .CommonAnnotations.SortedPairs }}{{ if $index }}, {{ end }}"{{ $commonAnnotations.Name }}": "{{ $commonAnnotations.Value }}"{{ end }}{{ "}" }}{{- end }}{{ "}" }}{{ end }}
   {{ define "sns.default.subject" }}[{{ .Status | toUpper }}{{ if eq .Status "firing" }}:{{ .Alerts.Firing | len }}{{ end }}]{{ end }}
Note

This template creates JSON from alphanumeric data. If your data has special characters, encode them before using this template.

To make sure that this template is used in outgoing notifications, reference it in your alertmanager_config block as follows:

alertmanager_config: |
  global:
  templates:
    - 'default_template'
Note

This template is for the entire message body as JSON. This template overwrites the entire message body. You cannot override the message body if you wish to use this specific template. Any overrides that are manually done will take precedence over the template.

For more information about: