simpleWebApp - simple web application with Gin framework written on Golang and running in Docker
- Golang 1.14
- Gin v1.6.0
- Docker Alpine latest
- Kubernetes v1.18.0
Build docker image:
docker build -t mothes/simplewebapp .
Login to Dockerhub:
docker login
Push to dockerhub:
docker push mothes/simplewebapp
Run docker container:
docker container run -ti --name simpleWebGoApp --rm -p 8080:8080 mothes/simplewebapp
Check results:
Run app in Kubernetes:
kubectl apply -f kubernetes/simpleWebApp.yml
p.s.: Don't forget to add secrets from private docker registry to Kubernetes
Check you Docker config:
cat ~/.docker/config.json
Add secret to Kubernetes:
kubectl create secret generic regcred \
--from-file=.dockerconfigjson=/root/.docker/config.json \
--type=kubernetes.io/dockerconfigjson
Check status of deployment in Kubernetes:
kubectl get deployments,svc,pods -l app=simple-web-app -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
deployment.apps/simple-web-app 3/3 3 3 17h simple-web-app mothes/simplewebapp app=simple-web-app
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/simple-web-app-svc NodePort 10.152.183.130 <none> 8080:30482/TCP 17h app=simple-web-app,color=blue
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/simple-web-app-8568875847-6j6tz 1/1 Running 1 10h 10.1.99.27 homeserver <none> <none>
pod/simple-web-app-8568875847-whdsz 1/1 Running 2 10h 10.1.99.29 homeserver <none> <none>
pod/simple-web-app-8568875847-z2tmb 1/1 Running 2 10h 10.1.99.30 homeserver <none> <none>
Check what's your endpoint in Kubernetes and test it:
curl http://10.100.102.5:30482/ping
{"message":"pong"}
HPA. Horizontal Pod Autoscaler.
kubectl describe hpa simple-web-app
Name: simple-web-app
Namespace: default
Labels: <none>
Annotations: CreationTimestamp: Sun, 05 Apr 2020 17:59:27 +0300
Reference: Deployment/simple-web-app
Metrics: ( current / target )
resource memory on pods: 3043328 / 100Mi
resource cpu on pods (as a percentage of request): 1% (1m) / 20%
Min replicas: 1
Max replicas: 8
Deployment pods: 1 current / 1 desired
Conditions:
Type Status Reason Message
---- ------ ------ -------
AbleToScale True ReadyForNewScale recommended size matches current size
ScalingActive True ValidMetricFound the HPA was able to successfully calculate a replica count from memory resource
ScalingLimited False DesiredWithinRange the desired count is within the acceptable range
Events: <none>
Roadmap:
- HPA manifest for autoscaling pods in Kubernetes ✔
- Helm3 chart for app
- Blue/Green deployments (or via Nginx Ingress or via Contour Ingress)
- Automatic tests (In Travis)
- Install Jenkins on top of Kubernetes ✔
- Migrate local Kubernetes setup, to GKE ✔
- Describe how to install HA Kubernetes cluster in AWS Amazon.
- Create Nginx Ingress controller as point of traffic for Jenkins ✔
- Create Contour Ingress controller as point of traffic for Jenkins
- Configure Nginx Ingress controller to use Basic Auth ✔
- Configure Nginx Ingress controller to use TLS (Let's Encrypt) ✔
- Create deployment in Jenkins + Deploy
Related articles:
How to deploy Golang Application to Kubernetes:
https://bit.ly/2Vo5eIP