ConferenceScheduler-CaseStudy

ConferenceScheduler is a rest api for an online conference scheduler.

Tech Stack

Java11, Spring Boot(web, test, data-mongodb, security, log4j2, validation), REST, MongoDB, Spring Security Oauth2, Maven, Junit5, Mockito, Assertj, Kubernetes

Rest API

• UserRegistryController : Restfull Service for user registry.

  • signUp : Method for user creation
    • Endpoint: http://127.0.0.1:8081/conference-scheduler/sign-up

• CustomerController : Restfull Service for conference operations.

  • scheduleConference : Method for scheduling a conference
    • Endpoint: http://127.0.0.1:8081/conference-scheduler/conference
  • getConference : Method for retrieving a conference data
    • Endpoint: http://127.0.0.1:8081/conference-scheduler/conference-details

Scheduling Details

Greedy algorithm is used to schedule conference. Greedy algorithms are a class of algorithms that make locally optimal choices at each step with the hope of finding a global optimum solution.

Deployment

• Install minikube and kubectl

  • https://minikube.sigs.k8s.io/docs/start/
  • https://kubernetes.io/docs/tasks/tools/

• For loadbanacer run command below

  minikube tunnel

• Run the commands below to build Image

  docker build -t eftmk/conferencescheduler:latest -f /ConferenceScheduler/src/main/resources/Dockerfile .

  eval $(minikube docker-env)

  • Note: If you want to use the pre-build image on Docker Hub, you should update imagePullPolicy of file Kubernetes/conference-scheduler.yaml as below

    spec:

    containers:

    name: conference-scheduler

    image: eftmk/conferencescheduler:latest

    imagePullPolicy: Always

• Run the command below to deploy application

  kubectl apply -f conference-scheduler.yaml

• Run the command below to undeploy application

  kubectl delete -f conference-scheduler.yaml

• For Kubernetes Dashboard, run the command below

  minikube dasboard

• Prometheus&Grafana : Run the commands below.

  kubectl create namespace monitoring

  helm repo add prometheus-community https://prometheus-community.github.io/helm-charts

  helm install k8spromethuesstack --namespace monitoring prometheus-community/kube-prometheus-stack

• Prometheus Console

  • Run the command below:

    kubectl port-forward service/k8spromethuesstack-kube-pr-prometheus 9090:9090 -n monitoring

  • Type 127.0.0.1:9090 to browser address line to open console page.

• Grafana Console

  • Run the command below:

    kubectl port-forward service/k8spromethuesstack-grafana 8080:80 -n monitoring

  • Type 127.0.0.1:8080 to browser address line to open console page. Username/password : admin/prom-operator

Logging

• Log4j framework is used for logging.

• Logs are stored on a Kubernetes Persistent Volume.

• To access the log file:

  • List the pods with command below and copy the app pod name

    kubectl get pods -n conference-scheduler-k8s

  • Then update the command below with PodName and run

    kubectl exec -n conference-scheduler-k8s -- tail -1000f /mnt/k8s/log/ConferenceScheduler.log

DB Access

• To access DB:
  • List the pods with command below and copy the MongoDB pod name

    kubectl get pods -n conference-scheduler-k8s

  • Then update the command below with PodName and run

    kubectl exec -it -n conference-scheduler-k8s -- mongosh -u user -p user

• Run the commands below to list the DB collections

  db.conference.find();

  db.user.find();

Rest Api Test

• Find the test requests xml under /Postman directory and import it from Postman. (Security configurations are ready)

• Spring Security OAuth2 is used for Endpoint security. To make rest api calls, firstly call the UserRegistryServis via http://127.0.0.1:8081/conference-scheduler/sign-up and register an user with email and password.

• After that, all rest calls must be added an access token.

• The registered email and password is used to create access token:

  • Postman ->New request -> Authorization tab ->

    Type = Oauth2
    
    Grant type = password
    
    Access Token URL = http://localhost:8081/oauth/token
    
    Client ID = ConferenceSchedulerClient
    
    Client Secret = secret
    
    Username = [email protected] (Note:Registered in the previous step)
    
    Password = ••••••• (Note:Created in the previous step)
    
    Scope = write
    
    Client Authentication = Send as Basic Auth Header
    

  • Press "Get New Access Token". Now token is created and added to request.

  • Each access token validity period is 12 hours.

• AccessToken should be added endpoints below before calling them:

  • Endpoint: http://127.0.0.1:8081/conference-scheduler/conference
  • Endpoint: http://127.0.0.1:8081/conference-scheduler/conference-details

Unit Test

• Test Frameworks: Junit5, Mockito, Assertj
• Coverage = %50