isabella232 / freshpod

Restart Pods on Minikube automatically on image rebuilds

freshpod

freshpod helps you automatically restart containers on Kubernetes when their image is updated.

It is designed for single-instance Kubernetes clusters, such as Minikube or Docker for Windows/Mac.

freshpod detects you rebuilt an image and it deletes the Kubernetes Pods are running that image. This way, your workload controller (such as Deployment) will create new Pods running the new image.

🆕 Check out Skaffold, a new tool by Google that simplifies local Kubernetes development experience. Skaffold supersedes freshpod.

Demo

This demo shows refactoring an application and running docker build will automatically restart the application with the new image on Minikube:

Install on Minikube

freshpod is available as an add-on for Minikube. You just need to enable it:

minikube addons enable freshpod

Install on “Docker for Mac/Windows”

If you’re using Kubernertes on Docker for Mac/Windows, you can directly apply the manifest used by Minikube:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/minikube/ec1b443722227428bd2b23967e1b48d94350a5ac/deploy/addons/freshpod/freshpod-rc.yaml

Try it out!

Get some test images and tag the :1.0 image as hello:latest:

eval $(minikube docker-env) # not necessary for docker-for-mac/windows
docker pull gcr.io/google-samples/hello-app:1.0
docker pull gcr.io/google-samples/hello-app:2.0
docker tag  gcr.io/google-samples/hello-app:1.0 hello:latest

Run a 2-replica Deployment and NodePort Service with hello:latest image:

kubectl run hello --image=hello --port 8080 --replicas=2 \
  --image-pull-policy=IfNotPresent

kubectl expose deploy/hello --type=NodePort

Visit the app (note the 1.0.0):

$ URL=$(minikube service hello --url)
$ curl "$URL"
Hello, world!
Version: 1.0.0
Hostname: hello-5766f88f9c-67lgz

Re-tag the hello:latest image with the 2.0 version:

docker tag gcr.io/google-samples/hello-app:2.0 hello

Visit the app again (note the version has changed to 2.0.0):

$ curl "$URL"
Hello, world!
Version: 2.0.0
Hostname: hello-5766f88f9c-h88df

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Contributing

See CONTRIBUTING.md for more information.

This is not an official Google product.