Deploy to Kubernetes with Github Actions

Deploy to Kubernetes with Github Actions v0

Github Actions is now in limited public beta and while trying it out for deploying to Kubernetes, I built this workflow:

	apiVersion: extensions/v1beta1
	kind: Deployment
	metadata:
	labels:
	app: myproject
	name: myproject
	namespace: default
	spec:
	progressDeadlineSeconds: 600
	replicas: 1
	revisionHistoryLimit: 10
	selector:
	matchLabels:
	app: myproject
	strategy:
	rollingUpdate:
	maxSurge: 1
	maxUnavailable: 1
	type: RollingUpdate
	template:
	metadata:
	creationTimestamp: null
	labels:
	app: myproject
	spec:
	containers:
	image: eu.gcr.io/PROJECT_ID/APPLICATION_NAME:TAG
	imagePullPolicy: Always
	name: ponycar
	resources: {}
	terminationMessagePath: /dev/termination-log
	terminationMessagePolicy: File
	dnsPolicy: ClusterFirst
	restartPolicy: Always
	schedulerName: default-scheduler
	securityContext: {}
	terminationGracePeriodSeconds: 30

view raw deployment.yaml hosted with ❤ by GitHub

	workflow "Build and deploy" {
	on = "push"
	resolves = [
	"notify on deploy",
	]
	}
	action "build image" {
	uses = "actions/docker/cli@76ff57a"
	args = "build -t myproject ."
	}
	action "tag image gcloud" {
	uses = "actions/docker/tag@76ff57a"
	args = ["myproject", "eu.gcr.io/$PROJECT_ID/$APPLICATION_NAME"]
	env = {
	PROJECT_ID = "myproject-220562"
	APPLICATION_NAME = "myproject"
	}
	needs = ["build image"]
	}
	action "gcloud auth" {
	uses = "actions/gcloud/auth@8ec8bfa"
	secrets = ["GCLOUD_AUTH"]
	}
	action "load docker credentials" {
	uses = "actions/gcloud/cli@8ec8bfa"
	args = ["auth", "configure-docker", "--quiet"]
	needs = ["gcloud auth"]
	}
	action "push to GCR" {
	needs = ["load docker credentials", "tag image gcloud"]
	uses = "actions/gcloud/cli@master"
	runs = "sh -c"
	env = {
	PROJECT_ID = "myproject-220562"
	APPLICATION_NAME = "myproject"
	}
	args = ["docker push eu.gcr.io/$PROJECT_ID/$APPLICATION_NAME"]
	}
	action "load GKE kube credentials" {
	uses = "actions/gcloud/cli@8ec8bfa"
	args = "container clusters get-credentials myproject --zone europe-west3-a --project myproject-220562"
	needs = ["gcloud auth"]
	}
	action "deploy to GKE" {
	needs = ["push to GCR", "load GKE kube credentials"]
	uses = "docker://gcr.io/cloud-builders/kubectl"
	env = {
	PROJECT_ID = "myproject-220562"
	APPLICATION_NAME = "myproject"
	DEPLOYMENT_NAME = "myproject"
	}
	runs = "sh -l -c"
	args = ["SHORT_REF=$(echo ${GITHUB_SHA} | head -c7) && cat $GITHUB_WORKSPACE/Kubernetes/deployment.yaml | sed 's/PROJECT_ID/'\"$PROJECT_ID\"'/' | sed 's/APPLICATION_NAME/'\"$APPLICATION_NAME\"'/' | sed 's/TAG/'\"$SHORT_REF\"'/' | kubectl apply -f - "]
	}
	action "verify GKE deployment" {
	needs = ["deploy to GKE"]
	uses = "docker://gcr.io/cloud-builders/kubectl"
	env = {
	DEPLOYMENT_NAME = "myproject"
	}
	args = "rollout status deployment/myproject"
	}
	action "notify on deploy" {
	uses = "niklasmerz/bin/curl@curl"
	needs = ["verify GKE deployment"]
	secrets = ["SLACK_HOOK"]
	args = ["-X", "POST", "--data-urlencode", "\"payload={\\\"channel\\\": \\\"#myproject\\\", \\\"username\\\": \\\"myproject-deployments\\\", \\\"text\\\": \\\"Deployment ready\\\", \\\"icon_emoji\\\": \\\":alarm_clock:\\\"}\"", "$SLACK_HOOK"]
	}

view raw main.workflow hosted with ❤ by GitHub

Lets go through it. This is workflow is based on the gcloud example action with my first own action which notifies me on Slack when the workflow is finished.

The first step is building my Dockerfile, I mentioned earlier and simultaneously logging into Google Cloud. I am running my Kubernetes Cluster on Google Cloud and using the Google Cloud Container Registry for my images. The image then gets tagged with the convenient tag action and pushed to the registry. Now I have image tagged with the branchname, short Git hash and the latest tag available.

The deploy to GKE action now uses the tag with the Git SHA and replaces the placeholders in my deployment file and applies it to the cluster.

After that the deployment gets verified and a Slack hook gets triggered to notify about the end of the workflow. The Slack hook is just a curl command to the URL I got from the Slack integration “Incomming webhooks”.