terraform-provider-kubectl

Kubectl Terraform Provider

The kubectl Kubectl provider enables Terraform to deploy Kubernetes resources. Unlike the official Kubernetes provider it handles raw manifests, leveraging kubectl directly to allow developers to work with any Kubernetes resource natively.

Running tests

Unit testing

This project uses ginkgo and gomega as unit test framework. Just run:

ginkgo -r

to execute them

Acceptance tests

Acceptance tests are provided for the kubectl_manifest resource. They can be executed with:

TF_ACC=1 go test kubectl/resource_*_test.go -v  -timeout 180m

by default they rely on a local minikube deployment. The kubernetes cluster endpoint is adjustable by configuring the following env variables:

• TP_KUBECTL_KUBECONFIG, default: "˜/.kube/config"
• TP_KUBECTL_KUBECONTEXT", default: "minikube"

Usage

Use go get to install the provider:

go get -u github.com/Typeform/terraform-provider-kubectl

Register the plugin in ~/.terraformrc:

providers {
  kubectl = "/$GOPATH/bin/terraform-provider-kubectl"
}

The provider takes optional configuration to specify a kubeconfig file:

provider "kubectl" {
  kubeconfig     = "/path/to/kubeconfig"
  kubecontext    = <context within kubeconfig> #optional
}

or

provider "kubectl" {
  kubecontent = <base64 encoded kubeconfig>
  kubecontext    = <context within kubeconfig> #optional
}

The k8s Terraform provider introduces a single Terraform resource, a k8s_manifest. The resource contains a content field, which contains a raw manifest.

variable "replicas" {
  type    = "string"
  default = 3
}

data "template_file" "nginx-deployment" {
  template = "${file("manifests/nginx-deployment.yaml")}"

  vars {
    replicas = "${var.replicas}"
  }
}

resource "k8s_manifest" "nginx-deployment" {
  content = "${data.template_file.nginx-deployment.rendered}"
}

In this case manifests/nginx-deployment.yaml is a templated deployment manifest.

apiVersion: apps/v1beta2
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx
spec:
  replicas: ${replicas}
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80

The Kubernetes resources can then be managed through Terraform.

$ terraform apply
# ...
Apply complete! Resources: 1 added, 1 changed, 0 destroyed.
$ kubectl get deployments
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   3         3         3            3           1m
$ terraform apply -var 'replicas=5'
# ...
Apply complete! Resources: 0 added, 1 changed, 0 destroyed.
$ kubectl get deployments
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   5         5         5            3           3m
$ terraform destroy -force
# ...
Destroy complete! Resources: 2 destroyed.
$ kubectl get deployments
No resources found.