Kuberentes-Mongo-Express

Deploying a sample Mongo-Express (Client) and MongoDB Stack in Kuberentes Cluster. We will do it in two ways:

• Stateless Way
• StatefulSets Way (Recommended)

Get Started

Clone the repository and navigate to the project root directory. Make sure you the following requirements:

• A running Kubernetes Cluster in cloud or Minikube (if testing locally)
• If you are using cloud provider, make sure to download the kubeconfig.yaml file and export it your enviroment as:

export KUBECONFIG=path-to-your-kubeconfig-file

1. Stateless Way

We will use the following components:

• Deployment - MondoDB and MongoExpress Pod
• Internal Service - MongoDB
• External Service (NodePort) - Mongo Express
• Config Map - For Database URLs
• Secret - For storing DB User and Password

Generate MongoDB Secrets

• AS, Kubernets Secrets are base64 encoded. We need to encode your credentials before applying to secret.

We can use any 3rd party tool for Windows. For Mac/Linux, run the following command and paste the resulting values in mongodb-sercret.yaml file:

echo "mongodb-root-username" | base64

echo "your mongodb-root-password" | base64

Apply kubectl commands in the following order

kubectl apply -f mongo-db-secret.yaml
kubectl apply -f mongo-db.yaml
kubectl apply -f mongo-db-configmap.yaml 
kubectl apply -f mongo-express.yaml

View the resources status using these kubectl get commands

kubectl get pod
kubectl get pod -o wide
kubectl get service
kubectl get secret
kubectl get configmap

(Minikube Users Only): Give a URL to external service in minikube

minikube service mongo-express-service

You will get a service IP address you can use to access the application. Hurray!

StatefulSets Way: MongoDB- Mongo Express via Helm Charts

We will use Linode for this purpose. However, you can do the same with other cloud providers. Just make sure to change the attributes accordingly.

• We will Utilize Linode StorageClass for PersistantVolume (to persist our data from MongoDB)
• Use Linode NodeBalancer as the entrypoint to our cluster which sends the request to internal Ingress Controller and then finally to the Pods via Services

1. Setup a Linode Kubernetes Engine. Follow steps here
2. Navigate to /helm-ingress-statefulsets-linode directory
3. Download kubeconfig and run the following commands:

  export KUBECONFIG={your-linode-kuberenetes-engine-kubeconfig-file}.yaml
  chmod o-r ~./k8s-mongo-express-kubeconfig.yaml
  chmod g-r ~./k8s-mongo-express-kubeconfig.yaml

4. Install Helm if you haven't already. The following commands will install the mongodb StatefulSet with values from mongodb-helm-values.yaml. This also creates Persistent Volume in Linode for each statefulsets.

  helm repo add bitnami https://charts.bitnami.com/bitnami

  helm install mongodb --values=mongodb-helm-values.yaml bitnami/mongodb

5. Create MongoExpress Deployment and Service

  kubectl apply -f mongo-express.yaml

6. Finaly, let's intall ingress-nginx controller in our cluster. This also creates Linode NodeBalancer cutomatically

  helm repo add nginx-stable https://helm.nginx.com/stable

  helm install nginx-ingres ingress-nginx/ingress-nginx 

7. Go to your Linode Dashbaord->LoadBalancer and grab the hostname url. In ingress.yaml file, paste the value under spec->rules->host

  kubectl apply -f ingress.yaml 

8. To delete the resources, you can simply use:

  helm delete mongodb //for statefulsets resources

  helm delete ingress //for ingress resources

That's it! Our MongoDB StatefulSets and MongoExpress Application is deployed!

Contributions

Contributions are highly welcomed. Please send a Pull Request with suggested changes or open an Issue to get things started!