thermograph/docker-compose.yml

# Thermograph production stack: the FastAPI app plus its PostgreSQL 18 database.
#
#   docker compose up -d --build      # or: make up
#
# POSTGRES_PASSWORD must be set at `docker compose` time — compose reads it from
# the repo-root .env for local runs (copy .env.example -> .env), and in prod the
# systemd unit's EnvironmentFile=/etc/thermograph.env puts it in the environment
# so `docker compose up` can interpolate it. It is used BOTH to initialize the db
# container and to build the app's THERMOGRAPH_DATABASE_URL below.

services:
  db:
    # PostgreSQL 18 + pg_duckdb (deploy/db/Dockerfile.db, FROM pgduckdb/pgduckdb:18-…,
    # which IS PostgreSQL 18). Lets the DB read the app's parquet climate cache
    # directly, e.g. SELECT * FROM read_parquet('/parquet/cache/*.parquet'). The init
    # script CREATE EXTENSIONs pg_duckdb on a fresh volume.
    build:
      context: .
      dockerfile: deploy/db/Dockerfile.db
    environment:
      POSTGRES_USER: thermograph
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:?set POSTGRES_PASSWORD}
      POSTGRES_DB: thermograph
    volumes:
      # Mount the volume at the PARENT of the data dir and let the PG18 image use
      # its own versioned subdir (/var/lib/postgresql/18/docker). Pinning PGDATA
      # directly at the mountpoint trips an initdb chmod on some Docker setups; the
      # whole tree still persists on the named volume this way.
      - pgdata:/var/lib/postgresql
      # Read the app's live parquet cache (the same appdata volume the app writes,
      # mounted read-only) — query it under /parquet/cache/*.parquet.
      - appdata:/parquet:ro
      - ./deploy/db/init:/docker-entrypoint-initdb.d
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U thermograph -d thermograph"]
      interval: 5s
      timeout: 5s
      retries: 10
    # Cap the DB at 2 CPUs. Compose v2 honors the top-level `cpus:`; the
    # deploy.resources block is the Swarm-style equivalent, kept for parity.
    cpus: 2.0
    deploy:
      resources:
        limits:
          cpus: "2.0"
    restart: unless-stopped
    # No host port on purpose: the app reaches Postgres as db:5432 on the
    # compose network. Nothing outside the stack should touch the database.

  app:
    build: .
    depends_on:
      db:
        condition: service_healthy
    environment:
      # Built from POSTGRES_PASSWORD; this `environment` value wins over anything
      # in env_file, so the URL always matches the db container's password.
      THERMOGRAPH_DATABASE_URL: postgresql+asyncpg://thermograph:${POSTGRES_PASSWORD}@db:5432/thermograph
      THERMOGRAPH_BASE: /
      PORT: 8137
      WORKERS: 4
      # One worker wins this lock and runs the subscription notifier / homepage
      # sweep; it lives on the appdata volume so it's shared across workers.
      THERMOGRAPH_SINGLETON_LOCK: /app/data/notifier.lock
    # Prod secrets live in /etc/thermograph.env: POSTGRES_PASSWORD,
    # THERMOGRAPH_AUTH_SECRET, THERMOGRAPH_VAPID_PRIVATE_KEY/_PUBLIC_KEY,
    # THERMOGRAPH_COOKIE_SECURE=1, mail/Discord keys, ... (see
    # deploy/thermograph.env.example). `required: false` so local `docker compose
    # up` works without that file — it reads POSTGRES_PASSWORD from repo-root .env.
    env_file:
      - path: /etc/thermograph.env
        required: false
    volumes:
      # Parquet cache, notifier.lock, homepage.json, vapid.json persist here.
      - appdata:/app/data
      - applogs:/app/logs
    cpus: 4.0
    ports:
      # Loopback only — host Caddy terminates TLS and reverse-proxies to this.
      - "127.0.0.1:8137:8137"
    restart: unless-stopped

volumes:
  pgdata: {}
  appdata: {}
  applogs: {}