---

labels:

- 'Stage-Alpha'

summary: Alertmanager webhook receiver for pubsub

---

# Introduction

This module lets

[Alertmanager](https://prometheus.io/docs/alerting/latest/alertmanager/)

publish alerts to [pubsub][doc:pubsub] via

[webhooks](https://prometheus.io/docs/alerting/latest/configuration/#webhook_config).

# Setup

The relevant pubsub nodes must be created and configured somehow.

Because the request IP address is used to publish, the `publisher`

affiliation should be given to the IP address Alertmanager sends

webhooks from.

# Configuration

## Prometheus

A Prometheus `rule_files` might contain something along these lines:

``` yaml

groups:

- name: Stuff

  rules:

  - alert: Down

    expr: up == 0

    for: 5m

    annotations:

      title: 'Stuff is down!'

    labels:

      severity: 'critical'

```

## Alertmanager

On the Alertmanager site the webhook configuration may look something

like this:

``` yaml

receivers:

- name: pubsub

  webhook_configs:

  - url: http://pubsub.localhost:5280/pubsub_alertmanager

```

And then finally some Alertmanager routes would point at that receiver:

``` yaml

route:

  receiver: pubsub

```

## Prosody

On the Prosody side, apart from creating and configuring the node(s)

that will be used, configure your pubsub service like this:

``` lua

Component "pubsub.example.com" "pubsub"

modules_enabled = {

    "pubsub_alertmanager",

}

-- optional extra settings:

alertmanager_body_template = [[

*ALARM!* {annotations.title?Alert} is {status}

Since {startsAt}{endsAt& until {endsAt}}

Labels: {labels%

  {idx}: {item}}

Annotations: {annotations%

  {idx}: {item}}

]]

alertmanager_node_template = "alerts/{alert.labels.severity}"

```

If no node template is given, either an optional part after

"pubsub_alertmanager" in the HTTP path is used as node, or the string

"alerts". Here, an alerts would be published to different nodes based on

the 'severity' label, so e.g. `alerts/critical` in this example.

## All Options

Available configuration options:

`alertmanager_body_template`

:   Template for the textual representation of alerts.

`alertmanager_node_template`

:   Template for the pubsub node name, defaults to `"{path?alerts}"`

`alertmanager_path_configs`

:   Per-path configuration variables (see below).

### Per-path configuration

It's possible to override configuration options based on the path suffix. For

example, if a request is made to `http://prosody/pubsub_alertmanager/foo` the

path suffix is `foo`. You can then supply the following configuration:

``` lua

alertmanager_path_configs = {

    foo = {

        node_template = "alerts/{alert.labels.severity}";

        publisher = "user@example.net";

    };

}

```