postgres_prestart.sh.j2

#!/bin/bash

check_orioledb_enabled() {
   local pg_conf="/etc/postgresql/postgresql.conf"
   if [ ! -f "$pg_conf" ]; then
       return 0
    fi
   grep "^shared_preload_libraries" "$pg_conf" | grep -c "orioledb" || return 0
}

get_shared_buffers() {
    local opt_conf="/etc/postgresql-custom/generated-optimizations.conf"
    if [ ! -f "$opt_conf" ]; then
        return 0
    fi
    grep "^shared_buffers = " "$opt_conf" | cut -d "=" -f2 | tr -d ' ' || return 0
}

update_orioledb_buffers() {
   local pg_conf="/etc/postgresql/postgresql.conf"
   local value="$1"
   if grep -q "^orioledb.main_buffers = " "$pg_conf"; then
       sed -i "s/^orioledb.main_buffers = .*/orioledb.main_buffers = $value/" "$pg_conf"
   else
       echo "orioledb.main_buffers = $value" >> "$pg_conf"
   fi
}

check_extensions_file() {
    local extensions_file="/root/pg_extensions.json"
    if [ ! -f "$extensions_file" ]; then
        echo "extensions: No extensions file found, skipping extensions versions check"
        return 1
    fi
    return 0
}

get_pg_cron_version() {
    if ! check_extensions_file; then
        return
    fi

    local version
    version=$(sudo -u postgres /var/lib/postgresql/.nix-profile/bin/jq -r '.pg_cron // empty' "/root/pg_extensions.json")
    if [ -z "$version" ]; then
        echo "pg_cron: Not specified in extensions file"
        return
    fi

    if ! [[ "$version" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
        echo "pg_cron: Invalid version format: $version"
        return
    fi

    echo "$version"
}

switch_pg_cron_version() {
    local version="$1"
    local switch_script="/var/lib/postgresql/.nix-profile/bin/switch_pg_cron_version"

    if [ ! -x "$switch_script" ]; then
        echo "pg_cron: No version switch script available"
        return
    fi

    echo "pg_cron: Switching to version $version"
    sudo -u postgres "$switch_script" "$version"
    echo "pg_cron: Version switch completed"
}

handle_pg_cron_version() {
    local version
    version=$(get_pg_cron_version)
    if [ -n "$version" ]; then
        switch_pg_cron_version "$version"
    fi
}

main() {
   # 1. pg_cron version handling 
   handle_pg_cron_version

   # 2. orioledb handling 
   local has_orioledb=$(check_orioledb_enabled)
   if [ "$has_orioledb" -lt 1 ]; then
       return 0
   fi
   local shared_buffers_value=$(get_shared_buffers)
   if [ ! -z "$shared_buffers_value" ]; then
       update_orioledb_buffers "$shared_buffers_value"
   fi
}

# Initial locale setup
if [ $(cat /etc/locale.gen | grep -c en_US.UTF-8) -eq 0 ]; then
   echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen
fi

if [ $(locale -a | grep -c en_US.utf8) -eq 0 ]; then
   locale-gen
fi

main