postgresrepmgr/docker-entrypoint-initdb.d/00-main.sh

#!/usr/bin/env bash

source /usr/local/bin/docker-entrypoint.sh

# the variable UPSTREAM indicates that a standby instance is requested, otherwise this is primary
if [[ -z $UPSTREAM ]]; then

  psql -c "CREATE USER repmgr WITH SUPERUSER ENCRYPTED PASSWORD '${REPLICATOR_PASSWORD}';"
  psql -c "CREATE DATABASE repmgr WITH OWNER repmgr;"
  psql -c 'ALTER USER repmgr SET search_path TO repmgr, "$user", public;'

  docker_temp_server_stop


  # ensure required entries in configuration
  # shellcheck disable=SC2129
  # echo "archive_command       = 'cp %p ${WAL_ARCHIVE:-/wal_archive}/%f'" >> /var/lib/postgresql/data/postgresql.conf
  echo "archive_command       = '/bin/true'" >> /var/lib/postgresql/data/postgresql.conf
  echo "archive_mode          = on" >> /var/lib/postgresql/data/postgresql.conf
  echo "hot_standby           = on" >> /var/lib/postgresql/data/postgresql.conf
  # echo "promote_trigger_file  = '/var/lib/postgresql/data/${TRIGGER_FILE:-i_am_primary}'" >> /var/lib/postgresql/data/postgresql.conf
  # echo "wal_keep_size         = ${WAL_KEEP_SIZE:-1GB}" >> /var/lib/postgresql/data/postgresql.conf
  echo "max_wal_senders       = 10" >> /var/lib/postgresql/data/postgresql.conf
  echo "max_replication_slots = 10" >> /var/lib/postgresql/data/postgresql.conf
  # ensure required entries in hba
  echo "local all          all                    trust"           > /var/lib/postgresql/data/pg_hba.conf
  echo "local replication  repmgr                 trust"          >> /var/lib/postgresql/data/pg_hba.conf
  echo "host  replication  repmgr  127.0.0.1/32   trust"          >> /var/lib/postgresql/data/pg_hba.conf
  echo "host  replication  repmgr  100.64.0.0/10  trust"          >> /var/lib/postgresql/data/pg_hba.conf
  echo "local repmgr       repmgr                 trust"          >> /var/lib/postgresql/data/pg_hba.conf
  echo "host  repmgr       repmgr  127.0.0.1/32   trust"          >> /var/lib/postgresql/data/pg_hba.conf
  echo "host  repmgr       repmgr  100.64.0.0/10  trust"          >> /var/lib/postgresql/data/pg_hba.conf
  echo "host  all          all     all            scram-sha-256"  >> /var/lib/postgresql/data/pg_hba.conf

  # create user for replication
  echo "node_id               = 1"                                                        >> /etc/repmgr.conf
  echo "node_name             = pg-0"                                                     >> /etc/repmgr.conf
  echo "conninfo              = 'host=pg-0 dbname=repmgr user=repmgr connect_timeout=2'"  >> /etc/repmgr.conf
  echo "data_directory        = '/var/lib/postgresql/data'"                               >> /etc/repmgr.conf
  echo "use_replication_slots = on"                                                       >> /etc/repmgr.conf
  echo "pg_bindir             = '/usr/lib/postgresql/15/bin/'"                            >> /etc/repmgr.conf


  # process selected tweaks
  if [[ -n $MAX_CONNECTIONS ]]; then
      echo "max_connections      = ${MAX_CONNECTIONS}" >> /var/lib/postgresql/data/postgresql.conf
  fi

 	set -- -c listen_addresses='*' -p "${PGPORT:-5432}"
  NOTIFY_SOCKET= \
  PGUSER="${PGUSER:-$POSTGRES_USER}" \
  pg_ctl -D "$PGDATA" \
  	-o "-c listen_addresses='*' -p ${PGPORT:-5432}" \
  	-w start

  /usr/lib/postgresql/15/bin/repmgr -f /etc/repmgr.conf primary register


else
# this is a standby

  docker_temp_server_stop

  rm -rf /var/lib/postgresql/data/*

  echo "node_id               = 2"                                                        >> /etc/repmgr.conf
  echo "node_name             = pg-1"                                                     >> /etc/repmgr.conf
  echo "conninfo              = 'host=pg-1 dbname=repmgr user=repmgr connect_timeout=2'"  >> /etc/repmgr.conf
  echo "data_directory        = '/var/lib/postgresql/data'"                               >> /etc/repmgr.conf
  echo "use_replication_slots = on"                                                       >> /etc/repmgr.conf
  echo "pg_bindir             = '/usr/lib/postgresql/15/bin/'"                            >> /etc/repmgr.conf


  until /usr/lib/postgresql/15/bin/repmgr -h pg-0 -U repmgr -f /etc/repmgr.conf standby clone --dry-run &> /dev/null
  do
    echo "Upstream host not ready..."
    sleep 300
  done
  /usr/lib/postgresql/15/bin/repmgr -h pg-0 -U repmgr -f /etc/repmgr.conf standby clone
  /usr/lib/postgresql/15/bin/repmgr -f /etc/repmgr.conf standby register

  docker_temp_server_start

fi