Hello Kong. Embedded in my medium article about "Spinning up an API Gateway with DBLess Kong Gateway". Draft link here https://medium.com/airasia-com-tech-blog/spinning-up-an-api-gateway-with-dbless-kong-gateway-2100be03619b

declarative.yaml

_format_version: "2.1"
_transform: true

services:
  - name: mock # any meaningful name to identify our API
    url: https://mockbin.org/bin/dd5b993d-c69b-48db-9036-829fb7955f58 # a remote backend that we will proxy to - clients will not know about this
    routes:
      - paths:
          - /mock # an API path that we will call
        methods:
          - GET # we will allow only the GET HTTP method for this route
        hosts:
          - example.hello-kong-test.com # we will serve only over a specific host for this route
        protocols:
          # - http # we will purposefully disallow plaintext HTTP traffic for this route
          - https # we will allow only HTTPS traffic (self-signed certificates will be provided out-of-the-box)

docker-compose.yml

version: '3'
services:
  kong_test:
    image: kong:3.0.1-alpine
    container_name: kong_test
    volumes: [ "./declarative.yaml:/etc/kong/declarative.yaml" ]
    
    # https://docs.konghq.com/gateway/2.6.x/reference/configuration/#environment-variables
    environment:
      KONG_DATABASE:           "off" # turns on DBLess mode
      KONG_DECLARATIVE_CONFIG: "/etc/kong/declarative.yaml"
      KONG_PROXY_LISTEN:       "0.0.0.0:8080, 0.0.0.0:8443 ssl"
      KONG_ADMIN_LISTEN:       "0.0.0.0:8001, 0.0.0.0:8002 ssl"
      KONG_STATUS_LISTEN:      "0.0.0.0:8101, 0.0.0.0:8102 ssl"
    
    ports:
      # Expose proxy ports in localhost
      # Opening standard http(80) and https(443) ports may require `sudo` privileges
      - 127.0.0.1:80:8080
      - 127.0.0.1:443:8443
      # expose Admin API ports in localhost 
      - 127.0.0.1:8901:8001
      - 127.0.0.1:8902:8002
      # expose Status API ports in localhost 
      - 127.0.0.1:8903:8101
      - 127.0.0.1:8904:8102