Running Flask on Kubernetes

Want to learn how to build this?

Check out the post.

Want to use this project?

Docker

Build the images and spin up the containers:

$ docker-compose up -d --build

Run the migrations and seed the database:

$ docker-compose exec server python manage.py recreate_db
$ docker-compose exec server python manage.py seed_db

Test it out at:

1. http://localhost:8080/
2. http://localhost:5001/books/ping
3. http://localhost:5001/books

Kubernetes

Minikube

Install and run Minikube:

1. Install a Hypervisor (like VirtualBox or HyperKit) to manage virtual machines
2. Install and Set Up kubectl to deploy and manage apps on Kubernetes
3. Install Minikube

Start the cluster:

$ minikube start --vm-driver=virtualbox
$ minikube dashboard

Volume

Create the volume:

$ kubectl apply -f ./kubernetes/persistent-volume.yml

Create the volume claim:

$ kubectl apply -f ./kubernetes/persistent-volume-claim.yml

Secrets

Create the secret object:

$ kubectl apply -f ./kubernetes/secret.yml

Postgres

Create deployment:

$ kubectl create -f ./kubernetes/postgres-deployment.yml

Create the service:

$ kubectl create -f ./kubernetes/postgres-service.yml

Create the database:

$ kubectl get pods
$ kubectl exec postgres-<POD_IDENTIFIER> --stdin --tty -- createdb -U postgres books

Flask

Build and push the image to Docker Hub:

$ docker build -t mjhea0/flask-kubernetes ./services/server
$ docker push mjhea0/flask-kubernetes

Make sure to replace mjhea0 with your Docker Hub namespace in the above commands as well as in kubernetes/flask-deployment.yml

Create the deployment:

$ kubectl create -f ./kubernetes/flask-deployment.yml

Create the service:

$ kubectl create -f ./kubernetes/flask-service.yml

Apply the migrations and seed the database:

$ kubectl get pods
$ kubectl exec flask-<POD_IDENTIFIER> --stdin --tty -- python manage.py recreate_db
$ kubectl exec flask-<POD_IDENTIFIER> --stdin --tty -- python manage.py seed_db

Ingress

Enable and apply:

$ minikube addons enable ingress
$ kubectl apply -f ./kubernetes/minikube-ingress.yml

Add entry to /etc/hosts file:

<MINIKUBE_IP> hello.world

Try it out:

1. http://hello.world/books/ping
2. http://hello.world/books

Vue

Build and push the image to Docker Hub:

$ docker build -t mjhea0/vue-kubernetes ./services/client \
    -f ./services/client/Dockerfile-minikube

$ docker push mjhea0/vue-kubernetes

Again, replace mjhea0 with your Docker Hub namespace in the above commands as well as in kubernetes/vue-deployment.yml

Create the deployment:

$ kubectl create -f ./kubernetes/vue-deployment.yml

Create the service:

$ kubectl create -f ./kubernetes/vue-service.yml

Try it out at http://hello.world/.