The most common kubectl commands

• Install kubectl

  curl -LO https://dl.k8s.io/release/curl -LS https://dl.k8s.io/release/stable.txt`/bin/linux/amd64/kubectl

• Makes the downloaded kubectl file executable

  chmod +x ./kubectl

• Moves the kubectl file to the /usr/local/bin system directory so that it can be accessed from anywhere on the system.

  sudo mv ./kubectl /usr/local/bin/kubectl

• Check kubectl version

  kubectl version --client

• Copy kubeconfig file

  cp booking-k8s-kubeconfig.yaml ~ kubectl --kubeconfig=booking-k8s-kubeconfig.yaml get nodes cp booking-k8s-kubeconfig.yaml .kube/ cp booking-k8s-kubeconfig.yaml config

• Install Helm

  sudo apt install helm

• Installs a Helm-chart named "my-release" from the specified Docker Hub repository

  helm install my-release oci://registry-1.docker.io/bitnamicharts/postgresql

• Outputs a list of pods in a Kubernetes cluster

  kubectl get pods

• Removes the installed Helm-chart named "my-release"

  helm delete my-release

• Sets port forwarding to access the PostgreSQL service through local port 5432

  kubectl port-forward --namespace default svc/postgresql 5432:5432 &

• Check the availability of resources

  kubectl describe pod postgresql-0

• Checks the available nodes in your Kubernetes cluster

  kubectl get nodes

• Checks for PVC-related errors or warnings

  kubectl describe pvc postgresql-pv-claim

• More information about the state of the PostgreSQL feed

  kubectl describe pod postgresql-0

• Get information about all nodes in your Kubernetes cluster

  kubectl get nodes -o wide

• Getting more detailed information about the status of nodes

  kubectl describe nodes

• Install PostgreSQL client

  sudo apt install postgresql-client-common

Connecting to PostgreSQL using Port-Forwarding

This guide provides step-by-step instructions on how to connect to PostgreSQL using port-forwarding. Port-forwarding allows you to access a PostgreSQL database running on a remote server from your local machine.

Steps

1. Open a terminal or command prompt on your local machine.

2. Set up port-forwarding to forward traffic from a local port to the PostgreSQL database port on the remote server. Use the following command:

   kubectl port-forward --namespace default svc/postgresql 5432:5432 &

3. Open your PostgreSQL client (e.g., DBeaver) on your local machine.

4. Configure the PostgreSQL client connection with the following details:

   Host: localhost or 127.0.0.1 Port: 5432 Database: "booking" User: "postgres" Password: "postgres"

5. Click "Connect" or a similar button to establish the connection to the PostgreSQL database.

6. You should now be connected to the PostgreSQL database running on the remote server through port-forwarding.

Booking service from scratch

Technologies

• Backend: Java 17, Spring 6, Spring Boot 3, Feign
• Frontend: TypeScript, React, Antd
• Deployment: Jenkins, Docker, Kubernetes
• Monitoring and logging: ELK, Grafana
• Queuing: Kafka
• Data storage: PostgreSQL
• Authorization: OAuth 2.0 and JWT
• Users management: OpenLDAP (?)
• Caching: Redis

  Services

  FE

• guest-fe
• host-fe
• admin-fe

  BE

• property-service
  • Creating and deleting property
  • Property management
  • Price
  • Availability
  • Description
  • Policy
• payment-service
  • chargeCard
  • refundTransaction
  • Receive money
• booking-service
  • Book property
  • Cancel booking and refund
• search-service
  • Search for property
• guest-service
  • Book property
  • Payments
• host-service
  • Manage property
  • Payments
• admin-service
  • Read-only access to all bookings
  • Initaite refund
• messaging-service
  • Send messages between guest, host and support
• mail-service
  • Send E-Mails to guest and host
• sms-service
  • Send SMS to guest and host

    Deployment

• Kubernetes
• Jenkins
• ELK
• Grafana
• Kafka (cluster, 3 nodes)
• PostgreSQL
• Redis (cluster, 3 nodes)
• OAuth Server

  Entites

• guest
  • name
  • phone
  • email
  • cards
• host
  • name: string
  • cards
  • properties: ref:property
• admin
• property
• payment
  • transaction
  • payment
  • refund
  • card
  • number
  • validUntil
  • cvv

    Processes

User Story As I want To do

Как администратор Я хочу доступ на чтение бронирований клиента Чтобы просматривать бронирования и отменять их при необходи

Booking

1. fe-client -> booking-service
   1. BookingRequest
      • property
      • dateFrom
      • dateTo
      • cardId
2. booking-service
   • property-service.isAvailable(propertyId)
   • guest-service.getGuest(token.guestId)
   • property-service.setUnavailable(property, dateFrom, dateTo)
   • guest-service.addBooking(property, dateFrom, dateTo, totalPrice, BookingStatus.RESERVED)
   • payment-service.chargeCard(cardId, amount)
   • guest-service.setBookingStatus(booking, BookingStatus.PAID)