Unleasherator

Kubernetes operator for managing Unleash - the open-source feature toggle service.

It has support for creating and managing Unleash instances and API tokens across multiple clusters or environments and only depends on Kubernetes native resources.

Used in production at the Norwegian Labour and Welfare Administration (NAV).

graph LR
  postgres[PostgreSQL]

  subgraph Kubernetes
    subgraph unleasherator-system
      unleasherator[Unleasherator]
    end

    subgraph my-namespace
      unleash[Unleash]
      apiToken[ApiToken]
      tokenSecret[Secret]

      deployment[Deployment]
    end
  end

  unleasherator -- manages --> unleash
  unleasherator -- manages --> apiToken
  apiToken -..- unleash
  apiToken -..-> tokenSecret
  unleash -- uses --> postgres

  tokenSecret -..-> deployment

Description

Unleasherator is a Kubernetes operator for managing Unleash instances and API tokens across multiple clusters or environments. It is built using the Kubebuilder framework and is cloud and infrastructure agnostic.

You'll find the documentation for various Unleash resources in the docs directory.

Creating an Unleash instance

The following example can be used with bitnami/postgresql helm chart to create an Unleash instance with a local postgresql database.

apiVersion: unleash.nais.io/v1
kind: Unleash
metadata:
  name: unleash
spec:
  size: 1
  database:
    secretName: postgres-postgresql
    secretPassKey: postgres-password
    host: postgres-postgresql
    databaseName: postgres
    port: "5432"
    user: postgres
    ssl: "false"
  networkPolicy:
    enabled: true
    allowDNS: true
    extraEgressRules:
    - to:
        - podSelector:
            matchLabels:
              app.kubernetes.io/name: postgresql
      ports:
        - protocol: TCP
          port: 5432

Sequence of events:

sequenceDiagram
    participant Unleasherator
    participant Kubernetes
    participant Unleash

    Unleasherator->>Kubernetes: Create Unleash secret
    Unleasherator->>Kubernetes: Create Unleash deployment
    Kubernetes->>Unleash: Start Unleash
    Unleasherator->>Kubernetes: Create Unleash service
    Unleasherator->>Kubernetes: Create Unleash ingress
    Unleasherator->>Kubernetes: Create Unleash network policy
    Unleasherator->>Unleash: Test connection

You can find more examples in the config/samples directory.

Getting Started

You’ll need a Kubernetes cluster to run against. You can use KIND to get a local cluster for testing, or run against a remote cluster.

Note: Your controller will automatically use the current context in your kubeconfig file (i.e. whatever cluster kubectl cluster-info shows).

Running on the cluster

Install Instances of Custom Resources:

kubectl apply -f config/samples/

Build and push your image to the location specified by IMG:

make docker-build docker-push IMG=<some-registry>/unleasherator:tag

Deploy the controller to the cluster with the image specified by IMG:

make deploy IMG=<some-registry>/unleasherator:tag

Uninstall CRDs

To delete the CRDs from the cluster:

make uninstall

Undeploy controller

UnDeploy the controller to the cluster:

make undeploy

Contributing

Contributions are welcome! Please see CONTRIBUTING.md for more info.

How it works

This project aims to follow the Kubernetes Operator pattern

It uses Controllers which provides a reconcile function responsible for synchronizing resources untile the desired state is reached on the cluster

Test It Out

Install the CRDs into the cluster:

make install

Run the controller in your cluster:

Since the controller needs to reach the Unleash instance it can not run locally, but must be deployed to the cluster.

make docker-build deploy logs

Modifying the API definitions

If you are editing the API definitions, generate the manifests such as CRs or CRDs, and corresponding Helm charts using:

make generate manifests helm

NOTE: Run make --help for more information on all potential make targets

More information can be found via the Kubebuilder Documentation

Metrics

There's prometheus metrics covering https://book.kubebuilder.io/reference/metrics-reference.html the default set of kubebuilder provided performance gauges as well as additional metrics for deployment status.

Metric	Type	Description
unleasherator_unleash_status	Gauge	Status of Unleash instances
unleasherator_remoteunleash_status	Gauge	Status of RemoteUnleash instances
unleasherator_api_token_status	Gauge	Status of ApiToken instances
unleasherator_federation_published_total	Counter	Number of Unleash federation messages published with status
unleasherator_federation_received_total	Counter	Number of Unleash federation messages received with status

License

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

nais / unleasherator