update-postgres.sh

#!/bin/bash

# Script to update the database
# The script creates a file db_backup.bck that stores the generated dump
# The script is designed to have generous sleep times to not break on slower servers

# NB: IF YOU TRY STARTING THE WRONG MAJOR VERSION CONTAINER AT FIRST THE SCRIPT WILL CURRENTLY FAIL LEADING TO DATA LOSS

if [ -f /.dockerenv ]; then
  echo "This script cannot be run inside a docker container.";
  exit 1;
fi

version=$1
config_file=${2:-$USER.env}

if [ -z "$version" ]; then
  echo "Please provide the desired PostgreSQL version as the first argument"
  exit 1
fi

# Set config file
if [ ! -f "$config_file" ]; then
  echo "Config file $config_file not found"
  exit 1
fi

source $config_file

# Check if the required environment variables are set
if [ -z "$DATE_POSTGRESQL_VERSION" ] || [ -z "$DATE_DB_PORT" ] || [ -z "$DATE_DB_PASSWORD" ] || [ -z "$COMPOSE_PROJECT_NAME" ]; then
  echo "Error: Required environment variables are not set"
  exit 1
fi

#Remove old backup file
rm db_backup.bck

# Make sure website is stopped
docker-compose down && sleep 15 && docker-compose up -d db

# Wait for db to start
sleep 15

# Check if the container is stopped
if [ -z `docker ps -q --no-trunc | grep $(docker-compose ps -q db)` ]; then
  echo "The container failed to start, This is probably because of wrong postgres version"
  exit 1
fi

# Check if any container is in a restart loop
if docker-compose exec db echo "Test command"; then
    echo "Test command ran successfully."
else
  echo "Test command failed to run."
  exit 1
fi

# Dump database to host file system
docker-compose exec -T db pg_dump -U postgres postgres > ./db_backup.bck

# Check that dump file is not empty
if [ ! -s "db_backup.bck" ]; then
  echo "Backup file is empty, exiting"
  exit 1
fi

# Stop container and remove volumes
docker-compose down --volumes && sleep 15

# Update the PostgreSQL image version in the env file
DATE_POSTGRESQL_VERSION=$version
sed -i "s/DATE_POSTGRESQL_VERSION=.*/DATE_POSTGRESQL_VERSION=${DATE_POSTGRESQL_VERSION}/" "$config_file"

# Stat the container with the new version
docker-compose up -d db && sleep 15

# Restore the database dump to new container
docker-compose exec -T db psql -U postgres -d postgres < ./db_backup.bck

# Stop container
docker-compose down