The docker-compose.yaml creates two containers:

• An "app" container serving the flask application on gunicorn server @ port 5001
• A "nginx" container serving the nginx service @ port 8081
• A nginx configuration (proxy pass directive) is used to route incoming requests to Nginx (port:8081) to the flask app named "app" running on port:5001.

How to run flask project using docker-compose:

• Git clone repository

gitclone https://github.com/sshuen30/flask-project.git

• cd into flask-project

• Start docker compose

docker-compose up -d

• Start docker compose and scale 3 containers for app

docker-compose up -d --build --scale app=3 (To create 3 containers for app)

• Stop docker compose

docker-compose down

• Browser: xxx.xxx.x.xx:8081

How to run flask project on Kubernetes:

• Copy flask-development.yaml and flask-service into a kubernetes cluster (eg, Google Cloud)
• Start a deployment

kubectl apply -f flask-development.yaml

• Start a load balancer service to route traffic to deployment - no need for nginx

kubectl apply -f flask-service.yaml 

• Get IP and port no. of service

kubectl get svc meme-flask-service 

• Scale deployment to 2 pods

kubectl scale deployment meme-flask-deployment --replicas=2 

• Change deployment image

kubectl set image deployment/meme-flask-deployment meme-flask=sshuen30/flask-app:v1