Finest project out there

Web app

This is a simple http node server with EJS templates.

Environment :

• API_URL: base url to the api

Api

Simple golang http server using gin which connects to a postgresql database.

It also runs migrations at start if configured so.

Environment :

• PG_USER: Username of the user in the postgresql database
• PG_PASSWORD: Password of the user in the postgresql database
• PG_HOSTNAME: Hostname of the machine running postgresql
• PG_DATABASE: Name of the database to connect to
• ENV: Mode to run the api in. Possible values :
  • dev: runs migrations and start http server
  • migrate: runs migrations and exit

How do I run it locally ?

Requirements

• Docker Engine
• Docker Compose as standalone binaries

Steps to follow

git clone https://github.com/do3-2023/mmo-kube

cd mmo-kube

# start the application
docker compose up -d

# access it
curl http://localhost:8080/

Pushing images to a registry

cd webapp # or api

# build it
docker build -t "$IMAGE_NAME:$TAG"

# push it
docker push "$IMAGE_NAME:$TAG"

Setting up k3d and the applications

Requirements

• Docker Engine
• Kubectl
• K3D

Steps to follow

Create this directory to persist the data later

mkdir /tmp/k3dvol

Create a cluster with the k3d cli

k3d cluster create mmo --api-port 6550 -p "1024:80@loadbalancer" --agents 2 --volume /tmp/k3dvol:/k3dvol

What does it do ?

• -p options maps the nodeport 80 which is the nodeport traefik is listening on to the 1024 port on your machine
• --volume option creates a volume on your machine so that persistent volumes can be retained
• --agents add two workers
• --api-port is the port of the kubeapi (optional)

Save the kubeconfig file, you can also put it somewhere else and specify KUBECONFIG env var

k3d kubeconfig get mmo > ~/.kube/config

Wait for cluster to start and apply the yaml files representing kubernetes resources

kubectl apply -f .kube/common/namespace

kubectl apply -f .kube/db

kubectl apply -f .kube/api

kubectl apply -f .kube/webapp

Wait for all deployments to be ready

curl http://localhost:1024

Delete the db deployment to check probes

kubectl delete deployment -n data db

Check the readiness of the webapp and api pods

kubectl get pods -n back
kubectl get pods -n front

They should not be ready.

Add the deployment again

kubectl apply -f .kube/db/deployment.yml

Check the readiness of the webapp and api pods

kubectl get pods -n back
kubectl get pods -n front

They should now be ready again. And the data should have been persisted.

Cleanup

k3d cluster rm mmo

sudo rm -rf /tmp/k3dvol