Volumes, redes e Compose

Persistir dados, conectar serviços e orquestrar tudo com docker compose.

O que você vai aprender

• Volumes nomeados vs bind mounts
• Redes bridge e DNS interno
• docker-compose.yml de verdade
• depends_on e restart policies

1. Volume para dados

docker volume create pgdata
docker run -d --name db \
  -e POSTGRES_PASSWORD=secret \
  -v pgdata:/var/lib/postgresql/data \
  postgres:16-alpine

2. Compose completo

services:
  api:
    build: .
    ports: ["8000:8000"]
    environment:
      DATABASE_URL: postgres://app:secret@db:5432/app
    depends_on: [db]
    restart: unless-stopped
  db:
    image: postgres:16-alpine
    environment:
      POSTGRES_USER: app
      POSTGRES_PASSWORD: secret
      POSTGRES_DB: app
    volumes:
      - pgdata:/var/lib/postgresql/data
    restart: unless-stopped
volumes:
  pgdata:

docker compose up -d --build
docker compose logs -f api
docker compose down

Sumário do curso