Key Features and Use Cases

The main idea behind helm-compose is to control / configure all helm related options as code by providing a compose file structure to configure everything you need to setup your helm based infrastructure.

Repository handling

Configuration based installation of all necessary repositories you define as a dependency in your helm-compose.yaml before triggering the installation of your releases.

apiVersion: 1.1

repositories:
  bitnami: https://charts.bitnami.com/bitnami

Multi release handling

The main feature of helm-compose is the ability to define a multitude of releases inside a single file. helm-compose supports single kubernetes-cluster and multi-cluster configuration.

Single cluster

Define as many releases as you would like for one or more namespaces.

apiVersion: 1.1

releases:
  wordpress:
    chart: bitnami/wordpress
    chartVersion: 14.3.2
    namespace: homepage
  wordpress2:
    chart: bitnami/wordpress
    chartVersion: 15.2.22
    namespace: homepage
repositories:
  bitnami: https://charts.bitnami.com/bitnami

Multi cluster

You can either use the kubeconfig options to point to a different path and use the kubecontext to select a specific context inside your kubeconfig.

apiVersion: 1.1

releases:
  wordpress-dev:
    chart: bitnami/wordpress
    chartVersion: 14.3.2
    namespace: homepage
    kubeconfig: ~/.kube/dev
  wordpress-int:
    chart: bitnami/wordpress
    chartVersion: 15.2.22
    namespace: homepage
    kubeconfig: ~/.kube/int
repositories:
  bitnami: https://charts.bitnami.com/bitnami

Environment variables

helm-compose utilizes a8m/envsubst to substitute environment variables inside your values block. This allows for better dealing with secrets that shouldn't be committed to your source control.

Expression	Meaning
`${var}`	Value of var (same as `$var`)
`${var-$DEFAULT}`	If var not set, evaluate expression as $DEFAULT
`${var:-$DEFAULT}`	If var not set or is empty, evaluate expression as $DEFAULT
`${var=$DEFAULT}`	If var not set, evaluate expression as $DEFAULT
`${var:=$DEFAULT}`	If var not set or is empty, evaluate expression as $DEFAULT
`${var+$OTHER}`	If var set, evaluate expression as $OTHER, otherwise as empty string
`${var:+$OTHER}`	If var set, evaluate expression as $OTHER, otherwise as empty string
`$${var}`	Escape expressions. Result will be `${var}`.

_{Most of the rows in this table were taken from here}

export WORDPRESS_ADMIN_PASSWORD="xxx"
export MARIADB_ROOT_PASSWORD="xxx"
helm compose up

apiVersion: 1.1

releases:
  wordpress:
    chart: bitnami/wordpress
    values:
      wordpressPassword: ${WORDPRESS_ADMIN_PASSWORD}
      mariadb.auth.rootPassword: ${MARIADB_ROOT_PASSWORD}

Revision handling

Revisions are essentially snapshots of your current helm-compose.yaml. Every time you trigger helm compose up a new revision will be created and stored (By default the last 10 revisions are kept).

Configuration

apiVersion: 1.1

storage:
  name: wordpress
  type: local # default: local
  numberOfRevisions: 5 # default: 10

Usage

You can list your revisions and get the content of your previous revisions via the helm compose list and helm compose get commands.

Rollback

Just select a revision you want to go back to. You can check the content with the helm compose get command and parse it directly into any helm compose command like so:

$ helm compose list
| Date             | Revision |
| ---------------- | -------- |
| 2023-05-24 23:56 |       12 |
| 2023-05-24 23:56 |       13 |
| 2023-05-24 23:57 |       14 |
| 2023-05-24 23:57 |       15 |
| 2023-05-24 23:57 |       16 |

# select revision 15 and use the pipe | operator to parse the content back into compose up with -f -
helm compose get 15 | helm compose up -f -