Alertmanager Webhook Signal

Note: The default config path is now /config.yaml

If you want to override the config location, set the CONFIG_PATH environment variable

This project creates a containerized http endpoint which listens for requests by an alertmanager webhook receiver and maps it to the signal-cli by bbernhard.

This is useful if you already have the signal-cli running for example as a home-assistant notifier.

Use a prometheus label recipients to specify where you want the signal message to be send.

It now supports alert webhooks from Grafana aswell, including a preview graph image!

Run container

docker run -d --name alertmanager-signal \
  -p 10000:10000 \
  -v $(pwd)/config.yaml:/config.yaml \
  docker.io/schlauerlauer/alertmanager-webhook-signal:1.1.1

Configuration

A config.yaml file is needed for configuration.

Example configuration:

# Alertmanager webhook url: /api/v3/alertmanager
# Grafana webhook url: /api/v3/grafana
server:
  port: 10000 # port this program listens on; required
  debug: false
signal:
  number: "+4923456" # the number you are sending messages from; required
  recipients: # default recipient(s), if the recipients label is not set in alert; required
  - "+49123123123"
  send: http://127.0.0.1:10001/v2/send # http endpoint of the signal-cli; required
alertmanager:
  ignoreLabels: # filter labels in the message; optional
  - "alertname"
  ignoreAnnotations: [] # filter annotations in the message; optional
  generatorURL: true # include generator URL in the message; optional (default: false)
  matchLabel: "recipients"
recipients: # optional list of recipient names and numbers for label matching
  alice: "+49123123123"
  bob: "+49234234234"
templates:
  grafana: |-
    {{ if eq .State "alerting" }}❗{{ else }}✅{{ end }} {{ .Title}}
    {{ .RuleName }}
    {{ .Message }}
    {{ .RuleUrl }}
  alertmanager: |-
    {{ if eq .Alert.Status "firing" }}❗{{ else }}✅{{ end }} Alert {{ .Alertname }} is {{ .Alert.Status }}

    {{- if gt (len (.Alert.Labels)) 0 }}

    Labels:
    {{- range $key, $value := .Alert.Labels }}
      - {{ $key }}: {{ $value }}
    {{- end }}
    {{- end }}

    {{- if gt (len (.Alert.Annotations)) 0 }}

    Annotations:
    {{- range $key, $value := .Alert.Annotations }}
      - {{ $key }}: {{ $value }}
    {{- end }}
    {{- end }}

    {{ if .Config.GeneratorURL -}}
    {{ .Alert.GeneratorURL}}
    {{ end -}}

Example PrometheusRule:

groups:
  - name: "test.rules"
    rules:
      - alert: "Watchdog default recipient"
        annotations:
          message: "Testalert default recipient"
        expr: 'vector(1)'
        for: "1m"

      - alert: "Watchdog named recipient"
        annotations:
          message: "Testalert named recipient"
        labels:
          recipients: "alice"
        expr: 'vector(1)'
        for: "1m"

Example Alertmanager config.yml:

global:

route:
  receiver: "signal"
  group_by: ["alertname"]
  group_wait: "5s"
  group_interval: "5m"
  repeat_interval: "3h"
receivers:
  - name: "signal"
    webhook_configs:
      - url: "http://127.0.0.1:10000/api/v3/alertmanager"
        send_resolved: true