helm chart for ejabberd

This repository holds a helm chart for ejabberd which

[...] is an open-source, robust, scalable and extensible realtime platform built using Erlang/OTP, that includes XMPP Server, MQTT Broker and SIP Service.

The chart configures the environment needed to build and run ejabberd kubernetes clusters. Additionally, the values.yaml file allows to include most of the configuration items, ejabberd offers in their ejabberd.yml.

The chart and its items can be found here.

Current state

The chart is under development, meaning there is room for enhancements and improvements. The issue tracker may be used to define roadmap items.

The chart is functional and needs testing. Please report back if anything does not work as expected.

This repository also contains a CI which tests basic activities, e.g. scaling, XMPP connectivity and traffic with processone's rtb as well as pod failures, kills, etc. with chaos mesh.

Contributors and PRs are also welcome.

Base image

The chart uses a custom ejabberd image, which is based on the official ejabberd container image. Currently only built for x86_64 due to an issue in QEMU - now resolved, however. So there will be soon an arm64 variant as well.

The image name is: ghcr.io/sando38/ejabberd:23.10-k8s1

Difference to the official ejabberd container image

This repository contains the patches applied to the official ejabberd releases in the image directory and the respective workflow file.

A short summary:

• Redesigned image based on Wolfi-OS to significantly improve the performance and resource usage.
• Includes an elector service to create kubernetes leases for pod leaders.
• Includes custom scripts to automatically detect and join a cluster as well as for performing healthchecks and self-healing.
• Slighlty modified ejabberdctl to use correct naming conventions for ejabberd clusters in kubernetes.
• Stipped/ hardened image by deleting all unneccessary packages from the image, e.g. package managers, etc.
• Includes additional libraries for ejabberd contribution modules ejabberd_auth_http and mod_ecaptcha.
• The three mentioned modules plus mod_s3_upload are installed in the image already.
• No ACME support, mounting your certs as k8s secrets is necessary.
• No support for CAPTCHA scripts, due to the nature of the stripped image.

Image tags

The patches are defined per release, hence a container image tag always bears the ejabberd release, e.g.: 23.10.

Furthermore, a suffix -k8s1 is used in case the image needs an update. The first release image has a suffix -k8s1.

Running this image with docker compose

The image may be used with docker compose using the following definitions:

version: '3'

services:
  ejabberd:
    image: ghcr.io/sando38/ejabberd:23.10-k8s3
    command: >
      sh -c "ejabberdctl foreground"
    environment:
      - ERLANG_NODE_ARG=ejabberd@localhost

Note: command and environment arguments are required to simulate the official image behhavior.

Merging the chart upstream

Yes, that is considered and actually also desired (link to discussion).