helmfile

Deploy Kubernetes Helm Charts

about

Helmfile is a declarative spec for deploying helm charts. It lets you...

• Keep a directory of chart value files and maintain changes in version control.
• Apply CI/CD to configuration changes.
• Periodically sync to avoid skew in environments.

To avoid upgrades for each iteration of helm, the helmfile executable delegates to helm - as a result, helm must be installed.

configuration syntax

The default helmfile is helmfile.yaml:

repositories:
  - name: roboll
    url: http://roboll.io/charts
    certFile: optional_client_cert
    keyFile: optional_client_key

context: kube-context					 # kube-context (--kube-context)

releases:
  # Published chart example
  - name: vault                            # name of this release
    namespace: vault                       # target namespace
    labels:                                  # Arbitrary key value pairs for filtering releases
      foo: bar
    chart: roboll/vault-secret-manager     # the chart being installed to create this release, referenced by `repository/chart` syntax
    version: ~1.24.1                       # the semver of the chart. range constraint is supported
    values: [ vault.yaml ]                 # value files (--values)
    secrets:
      - vault_secret.yaml                  # will attempt to decrypt it using helm-secrets plugin
    set:                                   # values (--set)
      - name: address
        value: https://vault.example.com
      - name: db.password
        value: {{ env "DB_PASSWORD" }}                   # value taken from environment variable. Will throw an error if the environment variable is not set. $DB_PASSWORD needs to be set in the calling environment ex: export DB_PASSWORD='password1'
      - name: proxy.domain
        value: "{{ env \"PLATFORM_ID\" }}.my-domain.com" # Interpolate environment variable with a fixed string

  # Local chart example
  - name: grafana                            # name of this release
    namespace: another                       # target namespace
    chart: ../my-charts/grafana              # the chart being installed to create this release, referenced by relative path to local chart
    values:
    - "../../my-values/grafana/values.yaml"             # Values file (relative path to manifest)
    - "./values/{{ env \"PLATFORM_ENV\" }}/config.yaml" # Values file taken from path with environment variable. $PLATFORM_ENV must be set in the calling environment.

installation

• go get github.com/roboll/helmfile or
• download one of releases or
• run as a container

getting started

Let's start with a simple helmfile and gradually improve it to fit your use-case!

Suppose the helmfile.yaml representing the desired state of your helm releases looks like:

releases:
- name: prom-norbac-ubuntu
  namespace: prometheus
  chart: stable/prometheus
  set:
  - name: rbac.create
    value: false

Sync your Kubernetes cluster state to the desired one by running:

helmfile sync

Congratulations! You now have your first Prometheus deployment running inside your cluster.

Iterate on the helmfile.yaml by referencing the configuration syntax and the cli reference.

cli reference

NAME:
   helmfile -

USAGE:
   helmfile [global options] command [command options] [arguments...]

COMMANDS:
     repos   sync repositories from state file (helm repo add && helm repo update)
     charts  sync charts from state file (helm upgrade --install)
     diff    diff charts from state file against env (helm diff)
     sync    sync all resources from state file (repos, charts and local chart deps)
     delete  delete charts from state file (helm delete)

GLOBAL OPTIONS:
   --file FILE, -f FILE         load config from FILE (default: "helmfile.yaml")
   --quiet, -q                  silence output
   --namespace value, -n value  Set namespace. Uses the namespace set in the context by default
   --selector,l value           Only run using the releases that match labels. Labels can take the form of foo=bar or foo!=bar.
	                              A release must match all labels in a group in order to be used. Multiple groups can be specified at once.
	                              --selector tier=frontend,tier!=proxy --selector tier=backend. Will match all frontend, non-proxy releases AND all backend releases.
	                              The name of a release can be used as a label. --selector name=myrelease
   --kube-context value         Set kubectl context. Uses current context by default
   --help, -h                   show help
   --version, -v                print the version

sync

The helmfile sync sub-command sync your cluster state as described in your helmfile. The default helmfile is helmfile.yaml, but any yaml file can be passed by specifying a --file path/to/your/yaml/file flag.

Under the covers, Helmfile executes helm upgrade --install for each release declared in the manifest, by optionally decrypting secrets to be consumed as helm chart values. It also updates specified chart repositories and updates the dependencies of any referenced local charts.

diff

The helmfile diff sub-command executes the helm-diff plugin across all of the charts/releases defined in the manifest.

To supply the diff functionality Helmfile needs the helm diff plugin installed. For Helm 2.3+ you should be able to simply execute helm plugin install https://github.com/databus23/helm-diff. For more details please look at their documentation.

secrets

The secrets parameter in a helmfile.yaml causes the helm-secrets plugin to be executed to decrypt the file.

To supply the secret functionality Helmfile needs the helm secrets plugin installed. For Helm 2.3+ you should be able to simply execute helm plugin install https://github.com/futuresimple/helm-secrets .

Paths Overview

Using manifest files in conjunction with command line argument can be a bit confusing.

A few rules to clear up this ambiguity:

• Absolute paths are always resolved as absolute paths
• Relative paths referenced in the helmfile manifest itself are relative to that manifest
• Relative paths referenced on the command line are relative to the current working directory the user is in

For additional context, take a look at paths examples

Labels Overview

A selector can be used to only target a subset of releases when running helmfile. This is useful for large helmfiles with releases that are logically grouped together.

Labels are simple key value pairs that are an optional field of the release spec. When selecting by label, the search can be inverted. tier!=backend would match all releases that do NOT have the tier: backend label. tier=fronted would only match releases with the tier: frontend label.

Multiple labels can be specified using , as a separator. A release must match all selectors in order to be selected for the final helm command.

The selector parameter can be specified multiple times. Each parameter is resolved independently so a release that matches any parameter will be used.

--selector tier=frontend --selector tier=backend will select all the charts

Examples

For more examples, see examples/REAMDME.md.