• Deployment

  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: nginx-deployment
    labels: ...
  spec:
    replicas: 2
    selector: ...
    template: ...
  

• Service

  apiVersion: v1
  kind: Service
  metadata:
    name: nginx-service
  spec:
    selector: ...
    ports: ...
  

What is YAML?

a data serialization language just like XML, JSON

Serialization language?

standard format to transfer data

YAML format compared to others

human readable and intuitive

• YAML ( line separation, indentation )

  microservices:
    - app: user-authentication
      port: 9000
      version: 1.0
  

• XML ( < > )

  <microservices>
    <microservices>
      <app>user-authentication</app>
      <port>9000</port>
      <version>1.0</version>
    </microservices>
  </microservices>
  

• JSON ( { } )

  {
    microservices: [
      {
        app: "user-authentication",
        port: 9000
        version: "1.0"
      }
    ]
  }
  

YAML Use Cases

• Docker Compose File
• Ansible
• Kubernetes

Basic Syntax

# this is yaml file
microservice:  # makes object
	- app: user-authentication  # first element of list
	  port: 9000
	  version: 1.7
    deployed: false  # true / false || on / off
  - app: login  # second element of list
    port: 9001
    versions: [1.5, 1,9]  # list too
    deployed: true