Docker migration helper

This repo contains a Dockerfile that can helps you in performing your Docker images migration.

This repository will:

Perform a temporary copy the old database
Initialize a new empty database with the default user / password couple provided as environment variables (POSTGRES_USER and POSTGRES_PASSWORD)
Run pg_upgrade from the copy of the old database to the new database
Replace the old database with the new one
Move the copy of the old database as sub-directory of the new database (in old_db directory, to allow rollback in case of failure)

Perform the migration

Create an outdated database:

mkdir test-db
docker run --rm --name testdb -u 1000 -e POSTGRES_PASSWORD=password -v $(pwd)/test-db:/var/lib/postgresql/data -it postgres:16

Perform the migration (you need to replace POSTGRES_USER and POSTGRES_PASSWORD with the credentials of the root user of the database):

docker run -u 1000 -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=password -v $(pwd)/test-db:/db --rm -it pierre42100/postgresmig:16to17