Postgres Upgrades and changes

[ObadaS]

Description

Updated Postgres image to the latest version (12 -> 18)
Added postgres configuration file to optimize the database (default values only, can use tools like https://pgtune.leopard.in.ua/ to get a configuration)
Updated documentation

Manual intervention

1. Maintenance mode on to avoid update on the database during the upgrade:

touch maintenance_mode/maintenance.on
git pull

2. Create the new postgres.conf file from the sample:

cp my-postgres_sample.conf my-postgres.conf

3. Rebuild docker containers to take into account the new image:

docker compose build --no-cache

4. Dump the database, remove it and reload it on the new configuration:

# Dump database
docker compose exec db bash -lc 'PGPASSWORD="$DB_PASSWORD" pg_dump -Fc -U "$DB_USERNAME" -d "$DB_NAME" -f /app/backups/upgrade-1.24.dump'

# Check that dump file is not empty
docker compose exec db bash -lc 'ls -lh /app/backups/upgrade-1.24.dump && pg_restore -l /app/backups/upgrade-1.24.dump | head'

/!\ Dangerous operation here: confirm that your dump worked before removing the database!

# Remove database
sudo rm -rf var/postgres

# Launch the new containers (containing the updated databse image and Restore from backup)
docker compose up -d
docker compose exec db bash -lc 'PGPASSWORD="$DB_PASSWORD" pg_restore --verbose --clean --no-acl --no-owner -U "$DB_USERNAME" -d "$DB_NAME" /app/backups/upgrade-1.24.dump'

See this for more details.

5 Disable maintenance mode:

rm maintenance_mode/maintenance.on

Checklist

• Code review by me
• Hand tested by me
• I'm proud of my work
• Code review by reviewer
• Hand tested by reviewer
• CircleCi tests are passing
• Ready to merge