K8 Microservices App with Kind

For this project let us consider a simple flask application which get’s user ip and provides The Users Country and City name

Client

Here the client.process_get(url) will take in a url and performs requests.get(url) and returns response.

Server

Now that the app is running let’s try to convert the following app into Micro services

Server Docker File

FROM python:3.9.5-slim-buster
ADD . ./app
WORKDIR /app
RUN pip3 install -r requirements.txt
EXPOSE 5003
CMD [ "python","app.py" ]

Client Docker File

FROM python:3.9.5-slim-buster
ADD . ./app
WORKDIR /app
RUN pip3 install -r requirements.txt
EXPOSE 5004
CMD [ "python","app.py" ]

Now that we have the Docker Container ready let’s write services and deployment for kubernetes.

The folder structure for the above project

be-depl.yaml

Here the resources are used to specify the configuration of pods.

fe-depl.yaml

Now let’s configure the services.

fe-svc.yaml

be-svc.yaml

Here the ports specify the ports to be exposed.

target port is the port of dockerized application while port specifies the port to be exposed to the environment.

Once all the above steps are finished let’s create a cluster and deploy the application

Since we are using kind we have to first create cluster using kind create command

1. Create a Cluster

kind create cluster --name ip-k8s

You can name your cluster however you want i named it ip-k8s

2. Let’s build the docker container

docker build -t be backend/
docker build -t fe frontend/

You have to be in root directory of project while running the above commands.

3. Let’s load our docker images into kind cluster

kind load docker-image fe --name ip-k8s
kind load docker-image be --name ip-k8s

4. Let’s apply the services and deployment to kubernetes

kubectl apply -f k8s

The above command will apply the services & deployments to kuberentes

Once after you applied all your changes you can simply run your service using the following command

kubectl port-forward svc/fe 9000:80

here svc denotes service and since we need to port forward frontend service we are targetting svc/fe and 9000 is the port to be exposed and 80 is the port of service.

Once you do that you can simply visit localhost:9000 to visit your page.

name: be
spec:
selector:
matchLabels:
app: be
template:
metadata:
labels:
app: be
spec:
containers:
- name: be
image: be
resources:
limits:
memory: "128Mi"
cpu: "500m"
ports:
- containerPort: 5003
imagePullPolicy: IfNotPresent