Dummy

This is a sample NodeJS app which prints Hey There and inserts a value in DB. This is just a POC for dev environment

NOT for Prod.

Pre-req: Application file is index.js and index-db.js minikube start # start cluster first

Deployment Steps:

mkdir WORKDIR && cd WORKDIR;

git clone https://github.com/avsprashant/Dummy.git # clone my repo

cd Dummy/

sh startUpScript.sh

This script will create all objects in this order :

Secret kind object from secrets.yml stores base 64 encrypted DB passwords,

PersistentVolume kind object from mysql-pv.yaml which creates a 20GB volume block at /mnt/data/

PersistentVolumeClaim kind object from mysql-pv.yaml defines a volume mount for /var/lib/mysql at above volume,

Pod kind object from database.yml creates a DB from this mysql:5.7 image,

Service kind object from database-service.yml exposes above POD,

Deployment kind object from helloworld-db.yml which is our app layer and

Service kind object from helloworld-db-service.yml generic object exposing above Deployment object.

Verification of deployed services:

kubectl get service # check services which get created instantly

kubectl get pods # check pods status, they will take sometime as they have to pull image and deploy

kubectl describe deployment # We have defined 2 replicas, describe for one of the deployment.

kubectl logs # view our NodeJs app prints logs here

minikube service helloworld-db-service --url # we get a end point as url

curl # curl should be installed, else try to do telnet and port

This should give hey there and visitor count. Our App is accessible from outside cluster i.e HOST.

Verification of App and DB authentication:

kubectl exec database -it -- mysql -u root -p # give password - "rootpassword" In mysql prompt, enter show databases; use helloworld; #helloworld is our DB select * from guests; #guests is our table, you should see some data.

du -s /mnt/data/ # make a note of DB space utilized CREATE TABLE Persons ( PersonID int, LastName varchar(255), FirstName varchar(255), Address varchar(255), City varchar(255) ); insert into Persons(PersonID) values(100); # Add some sample data and again check DB space utilized

Verification of Data persistence @ /mnt/data/ in Host:

kubectl exec database -- touch /var/lib/mysql/abc.txt # create a file in DB pod

ls -l /mnt/data/abc.txt # access it on HOST @ /mnt/data/

Data is getting stored in /var/lib/mysql which is inturn mounted at /mnt/data/