docker-compose.yaml

version: "3.8"

services:
  # A nats cluster with 3 nodes
  nats:
    image: nats:2.10.14-alpine
    command:
      - "--debug"
      - "-m"
      - "8222"
      - "--cluster"
      - "nats://0.0.0.0:6222"
      - "--routes"
      # Note that this needs to be prefixed with the
      # name of the directory that the docker-compose file is in.
      # In this case it's "nats-consumers-78214263" (a mnemonic and question ID)
      - "nats://nats-consumers-78214263-nats-1:6222"
    hostname: nats
    deploy:
      replicas: 3
    healthcheck:
      test: ["CMD", "wget", "--spider", "-q", "http://localhost:8222/varz"]
      interval: 10s
      timeout: 5s
      retries: 3

  # The producer
  # You can scale this up via `docker compose scale producer=n`
  # to see how the consumers handle the load
  producer:
    deploy:
      replicas: 1
    build:
      context: .
      args:
        - BINARY_NAME=producer
    command: ["/usr/local/bin/producer"]
    environment:
      - PRODUCER_NATS_URL=nats://nats:4222
      - PRODUCER_PRODUCERS=1
    depends_on:
      nats:
        condition: service_healthy
  # The consumer
  # You can scale this up via `docker compose scale consumer=n`
  # to see how the consumers handle the load
  consumer:
    deploy:
      replicas: 1
    build:
      context: .
      args:
        - BINARY_NAME=consumer
    command: ["/usr/local/bin/consumer"]
    environment:
      - CONSUMER_NATS_URL=nats://nats:4222
      - CONSUMER_TOPIC=test.>
      - CONSUMER_CONSUMERS=15000
    depends_on:
      nats:
        condition: service_healthy