docker-compose.postgres-test.yml

# A disposable PostgreSQL 16 for dbprofiler's integration tests.
#
# Every credential here is a ${...} substitution read from .env.test.local,
# which is gitignored. This file holds no password, no port, and no connection
# string, so it is safe to commit and safe to read in a public repository.
#
#   docker compose --env-file .env.test.local \
#       -f docker-compose.postgres-test.yml up -d --wait
#
# See docs/TESTING.md for the full loop, including how to reset the volume.

name: dbprofiler-postgres-test

services:
  postgres:
    image: postgres:16
    # :? rather than a default value. A default would let a typo in the env
    # file start a container with credentials nobody chose, and the integration
    # test would then fail somewhere less obvious than here.
    environment:
      POSTGRES_USER: ${DBPROFILER_TEST_PGUSER:?missing from .env.test.local}
      POSTGRES_PASSWORD: ${DBPROFILER_TEST_PGPASSWORD:?missing from .env.test.local}
      POSTGRES_DB: ${DBPROFILER_TEST_PGDATABASE:?missing from .env.test.local}
    command:
      - postgres
      # pg_stat_statements needs a preload, so the profiler's degradation path
      # is not the one under test here. track=all counts statements inside
      # functions too, which is closer to what a real source looks like.
      - -c
      - shared_preload_libraries=pg_stat_statements
      - -c
      - pg_stat_statements.track=all
    ports:
      # Loopback only. The fixtures are disposable and the credentials are
      # synthetic, but a PostgreSQL listening on 0.0.0.0 is not something to
      # leave running on a laptop on a conference network.
      - "127.0.0.1:${DBPROFILER_TEST_PGPORT:?missing from .env.test.local}:5432"
    volumes:
      - pgdata:/var/lib/postgresql/data
      # Runs once, when the volume is empty. `down -v` and up again is how you
      # get a clean database; see docs/TESTING.md.
      - ./testdata/postgres-test-init.sql:/docker-entrypoint-initdb.d/10-dbprofiler.sql:ro
    healthcheck:
      # $$ escapes the substitution so the shell inside the container expands
      # it, not Compose. --wait blocks on this, so a test run never races the
      # first connection.
      test: ["CMD-SHELL", "pg_isready -U \"$$POSTGRES_USER\" -d \"$$POSTGRES_DB\""]
      interval: 2s
      timeout: 5s
      retries: 30
      start_period: 5s

volumes:
  pgdata: