# The reference TLS proxy overlay (ADR 0044's `proxy` service). Use it on top of the base:
#
#   docker compose -f compose.yaml -f compose.proxy.yaml up -d
#
# Caddy terminates TLS with publicly trusted ACME certificates and publishes the deployment's only
# ports. It reaches `api` and `object-storage` on the `edge` network, which this overlay creates and
# attaches them to; `postgres` is never on it.
#
# Client addresses. Caddy is the only peer the API trusts to say who the client is: this overlay
# puts the API in trusted-proxy mode for exactly the proxy's fixed address, and the Caddyfile
# overwrites X-Forwarded-For with the one address Caddy resolved. Because the address must be
# fixed for "only the proxy" to be expressible, `edge` has an explicit subnet whose dynamic range is
# its lower half; the proxy (and the tunnel connector, if used) take addresses from the upper half,
# which Docker never hands to another container.

services:
  proxy:
    image: caddy:2.11.4-alpine@sha256:6aeddd44c3078b0f9a35206472a11420648a79c184603ef95957d0a20044cb2b
    restart: unless-stopped
    read_only: true
    tmpfs:
      - /tmp
    cap_drop:
      - ALL
    cap_add:
      - NET_BIND_SERVICE
    security_opt:
      - no-new-privileges:true
    ports:
      # 80 answers ACME HTTP-01 challenges and redirects everything else to HTTPS. Set
      # EKKLESIA_PUBLISH_ADDRESS to bind one host interface instead of all of them.
      - "${EKKLESIA_PUBLISH_ADDRESS:-0.0.0.0}:${EKKLESIA_HTTP_PORT:-80}:80"
      - "${EKKLESIA_PUBLISH_ADDRESS:-0.0.0.0}:${EKKLESIA_HTTPS_PORT:-443}:443"
      - "${EKKLESIA_PUBLISH_ADDRESS:-0.0.0.0}:${EKKLESIA_HTTPS_PORT:-443}:443/udp"
    environment:
      EKKLESIA_HOSTNAME: ${EKKLESIA_HOSTNAME:?EKKLESIA_HOSTNAME is required, for example ekklesia.example.org}
      EKKLESIA_STORAGE_HOSTNAME: ${EKKLESIA_STORAGE_HOSTNAME:?EKKLESIA_STORAGE_HOSTNAME is required, for example storage.ekklesia.example.org}
      # The split topology only (ADR 0045, Caddyfile.split.example), where EKKLESIA_HOSTNAME is the
      # API's hostname and this is the Dashboard's. Caddyfile.example ignores it; the split
      # configuration refuses to start without it.
      EKKLESIA_DASHBOARD_HOSTNAME: ${EKKLESIA_DASHBOARD_HOSTNAME:-}
      EKKLESIA_ACME_EMAIL: ${EKKLESIA_ACME_EMAIL:?EKKLESIA_ACME_EMAIL is required for ACME account notices}
      EKKLESIA_TUNNEL_ADDRESS: ${EKKLESIA_TUNNEL_ADDRESS:-10.249.250.253}
    volumes:
      - ${EKKLESIA_CADDYFILE:-./Caddyfile}:/etc/caddy/Caddyfile:ro
      # The installation-private CA, so Caddy can verify object-storage's certificate.
      - ${EKKLESIA_TLS_DIR:-/etc/ekklesia/tls}/ca.crt:/etc/caddy/ekklesia-ca.crt:ro
      - proxy-data:/data
      - proxy-config:/config
    networks:
      edge:
        ipv4_address: ${EKKLESIA_PROXY_ADDRESS:-10.249.250.254}
    depends_on:
      api:
        condition: service_healthy
      object-storage:
        condition: service_healthy

  api:
    networks:
      edge: {}
    environment:
      # Exactly one trusted peer: this proxy. Set here from the same variable that fixes the proxy's
      # address, so the two cannot drift apart. These override any value in ekklesia.env.
      EKKLESIA_CLIENT_ADDRESS_MODE: trusted-proxy
      EKKLESIA_CLIENT_ADDRESS_HEADER: x-forwarded-for
      EKKLESIA_CLIENT_ADDRESS_TRUSTED_PROXIES: ${EKKLESIA_PROXY_ADDRESS:-10.249.250.254}/32

  object-storage:
    networks:
      edge: {}

networks:
  edge:
    ipam:
      config:
        - subnet: ${EKKLESIA_EDGE_SUBNET:-10.249.250.0/24}
          # Docker assigns dynamic addresses only from this range. Keep the fixed proxy and tunnel
          # addresses outside it.
          ip_range: ${EKKLESIA_EDGE_DYNAMIC_RANGE:-10.249.250.0/25}

volumes:
  proxy-data:
  proxy-config: