---
version: "3.8"

services:
  
  db:
    environment:
      - AVAILABLE_RAM_MB=${DB_MEMORY_LIMIT}
      - PG_DB_TYPE
      - PG_STORAGE_TYPE
      # - POSTGRES_START_CMD=
      #   - postgres
      #     -c max_connections=200
      #     -c shared_buffers=${DB_MEMORY_LIMIT}MB
      #     # -c shared_preload_libraries='pg_stat_statements'
      #     # -c statement_timeout=1800000
      #     # -c pg_stat_statements.track=all
    # shm_size: ${DB_MEMORY_LIMIT} # unsupported by docker swarm
    tmpfs:
      - /tmp:size=${DB_MEMORY_LIMIT}M
    entrypoint: ["/postgres-entrypoint.sh"]
    #entrypoint: ['tail', '-f', '/dev/null'] # can replace entrypoint when the Postgres DB is corrupted and won't start
    configs:
        - source: postgres_entrypoint
          target: /postgres-entrypoint.sh
          mode: 0555
        - source: postgres_tune
          target: /postgres-tune.sh
          mode: 0555
        - source: postgres_conf_tmpl
          target: /postgres.conf.tmpl
          mode: 0444
        - source: bash_envsubst
          target: /bash-envsubst.sh
          mode: 0444


configs:
  postgres_entrypoint:
    name: ${STACK_NAME}_postgres_entrypoint_${POSTGRES_ENTRYPOINT_VERSION:-v6}
    file: postgres/postgres-entrypoint.sh
  postgres_tune:
    name: ${STACK_NAME}_postgres_tune_${POSTGRES_TUNE_VERSION:-v1}
    file: postgres/postgres-tune.sh
  postgres_conf_tmpl:
    name: ${STACK_NAME}_postgres_conf_tmpl_${POSTGRES_CONF_TMPL_VERSION:-v2}
    file: postgres/postgres.conf.tmpl
  bash_envsubst:
    name: ${STACK_NAME}_bash_envsubst_${BASH_ENVSUBST_VERSION:-v1}
    file: postgres/bash-envsubst.sh