Basic XMPP Alertmanager Webhook Receiver for Prometheus

This repository has been made to receive Prometheus alerts on my Phone without relying on a third party provider.
To do so I have installed on my Raspberry PI:

• Prometheus
• Alertmanager
• Prosody, an XMPP server

On my phone, I have just installed an XMPP client.

go install github.com/trazfr/prometheus-xmpp-alerting@latest

This program is configured through a JSON file.

To run, just prometheus-xmpp-alerting config.json

This example of configuration file shows:

• the webhook listening on 127.0.0.1:9091
• when the instance is starting, it sends to everyone Prometheus Monitoring Started
• it sends a different message depending on a severity label
• it sends a message when an alert is resolved
• it overrides the timezone to Europe/Paris (optional, can either UTC, Local or from the list of timezones). By default it keeps the timezone from the message sent by Alertmanager
• the templates are in plain text. The possible values are text or html using XEP-0071 which is deprecated. If omitted, it defaults to text
• the program uses the XMPP user [email protected] with a password
• when it is working, it has the status Monitoring Prometheus...
• it doesn't use a TLS socket due to the tls flag. Actually it will use STARTTLS due to the server configuration
• it doesn't check the TLS certificates thanks to tls_insecure (for some reason, it doesn't work on my Prosody install, but as I'm connecting to localhost, it doesn't matter)
• each time it receives an alert, it sends a notification to
  • 2 XMPP accounts [email protected] and [email protected]
  • 1 MUC [email protected] using the nick monitoring-bot

{
    "listen": "127.0.0.1:9091",
    "startup_message": "Prometheus Monitoring Started",
    "firing": "{{ if eq .Labels.severity \"error\" }}🔥{{ else if eq .Labels.severity \"warning\" }}💣{{ else }}💡{{ end }} Firing {{ .Labels.alertname }}\n{{ .Annotations.description }} since {{ .StartsAt.Format \"2006-01-02 15:04:05\" }}\n{{ .GeneratorURL }}",
    "resolved": "{{ .Labels.alertname }} resolved at {{ .EndsAt.Format \"2006-01-02 15:04:05\" }}",
    "time_zone": "Europe/Paris",
    "format": "text",
    "xmpp": {
        "user": "[email protected]",
        "password": "MyXmppPassword",
        "status": "Monitoring Prometheus...",
        "tls": false,
        "tls_insecure": true,
        "send_notif": [
            "[email protected]",
            "[email protected]"
        ],
        "send_muc": [
            {
                "room": "[email protected]",
                "nick": "monitoring-bot"
            }
        ]
    }
}

Usually, the admin creates DNS records to resolve the XMPP server.
In some circumstances such records are not created.

The field .xmpp.override_server must be set to point to the right server:

{
    "xmpp": {
        "override_server": "192.168.0.42:4212",
        // ...
    }
    // ...
}

This program uses HTTP with 3 different paths:

• /alert is used by Prometheus' Alertmanager to send alerts
• /send is mainly used for debugging or if one just want to send simple message from another program. To send a message:
  • curl -H 'Content-Type: text/plain' -X POST <my_ip:port>/send -d 'my message'
  • curl -H 'Content-Type: text/html' -X POST <my_ip:port>/send -d '<p style="color:green;font-weight:bold;">Green text</p>' if the client supports the deprecated XEP-0071
• /metrics to be scrapped by Prometheus. It exposes some basic metrics