# PostgreSQL for integration tests.
# Usage: make test-pg          (starts, runs, tears down)
#        make test-pg-down     (tear down a stack left behind)
#
# THE HOST PORT IS EPHEMERAL AND THAT IS THE POINT (TASK-2708). It used to be
# hardcoded to 5445, which let exactly ONE worktree run the Postgres leg at a
# time: a second `make test-pg` failed with "port is already allocated", and a
# stack orphaned by a removed worktree blocked the port for everyone until
# somebody found and reaped it. With concurrent worktrees the normal operating
# mode, that produced three incidents in one afternoon — including a run that
# exited 2 having executed NO TESTS, which reads a lot like green at a glance.
#
# Docker assigns the host port; the Makefile reads it back with
# `docker compose port postgres 5432` and builds PAD_TEST_POSTGRES_URL from it.
# Do not reintroduce a fixed host port here, and do not hardcode one in a
# script — derive it, or you have rebuilt the collision.
#
# The Makefile also sets an EXPLICIT compose project name, keyed to the
# checkout's absolute path. Compose's default is the directory BASENAME, which
# is per-worktree in the usual layout but NOT unique — two checkouts sharing a
# basename would share a stack, and one `down -v` would tear down the other's
# database mid-run. An earlier version of this comment claimed the default was
# already sufficient; it is not, and the Makefile no longer relies on it.

services:
  postgres:
    image: postgres:17-alpine
    environment:
      POSTGRES_USER: pad
      POSTGRES_PASSWORD: pad
      POSTGRES_DB: pad
    ports:
      # No host side: Docker picks a free port. Read it back rather than
      # assuming one (see the header).
      - "5432"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U pad"]
      interval: 2s
      timeout: 2s
      retries: 10
    tmpfs:
      - /var/lib/postgresql/data  # RAM-backed for speed